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draft-ietf-webdav-rfc2518bis-06.txt --> draft-ietf-webdav-rfc2518bis-07.txt

WebDAV L. Dusseault
Internet-Draft OSAF
Expires: January 15, 2005 16, 2006 J. Crawford
IBM
July 17, 2004 15, 2005

HTTP Extensions for Distributed Authoring - WebDAV RFC2518 bis
draft-ietf-webdav-rfc2518bis-06
draft-ietf-webdav-rfc2518bis-07

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Abstract

WebDAV consists of a set of methods, headers, and content-types
ancillary to HTTP/1.1 for the management of resource properties,
creation and management of resource collections, namespace
manipulation, and resource locking (collision avoidance).

RFC2518 was published in February 1998, and this draft makes minor
revisions mostly due to interoperability experience.

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Table of Contents

1. Introduction

This document describes an extension to the HTTP/1.1 protocol that
allows clients to perform remote web content authoring operations.
This extension provides a coherent set of methods, headers, request
entity body formats, and response entity body formats that provide
operations for:

Properties: The ability to create, remove, and query information
about Web pages, such as their authors, creation dates, etc. Also,
the ability to link pages of any media type to related pages.

Collections: . . . . . . . . . . . . . . . . . . . . . . . . 7
2. Notational Conventions . . . . . . . . . . . . . . . . . . . 9
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 10
4. Data Model for Resource Properties . . . . . . . . . . . . . 11
4.1 The ability to create sets of documents Resource Property Model . . . . . . . . . . . . . . 11
4.2 Properties and to retrieve
a hierarchical membership listing (like a directory listing in a file
system).

Locking: The ability to keep more than one person from working on a
document at the same time. This prevents the "lost update problem",
in which modifications are lost as first one author then another
writes changes without merging the other author's changes.

Namespace Operations: The ability to instruct the server to copy HTTP Headers . . . . . . . . . . . . . . 11
4.3 XML Usage . . . . . . . . . . . . . . . . . . . . . . . 11
4.4 Property Values . . . . . . . . . . . . . . . . . . . . 12
4.5 Property Names . . . . . . . . . . . . . . . . . . . . . 13
4.6 Source Resources and
move Output Resources . . . . . . . . . 14
5. Collections of Web resources.

Requirements and rationale for these operations are described in a
companion document, "Requirements for a Distributed Authoring Resources . . . . . . . . . . . . . . . . 15
5.1 HTTP URL Namespace Model . . . . . . . . . . . . . . . . 15
5.2 Collection Resources . . . . . . . . . . . . . . . . . . 15
6. Locking . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.1 Exclusive Vs. Shared Locks . . . . . . . . . . . . . . . 17
6.2 Required Support . . . . . . . . . . . . . . . . . . . . 18
6.3 Lock Tokens . . . . . . . . . . . . . . . . . . . . . . 18
6.4 Lock Token URI Schemes . . . . . . . . . . . . . . . . . 19
6.5 Lock Capability Discovery . . . . . . . . . . . . . . . 19
6.6 Active Lock Discovery . . . . . . . . . . . . . . . . . 20
6.7 Locks and
Versioning Protocol for the World Wide Web" (RFC2291) [15].

This standard does not specify the versioning operations suggested Multiple Bindings . . . . . . . . . . . . . . 20
7. Write Lock . . . . . . . . . . . . . . . . . . . . . . . . . 21
7.1 Lock Owner . . . . . . . . . . . . . . . . . . . . . . . 21
7.2 Methods Restricted by
RFC2291 [15]. That work was done in a separate document, "Versioning
Extensions to WebDAV" (RFC3253) [18].

The sections below provide a detailed introduction to resource
properties (Section 4), collections of resources (Section 5), Write Locks . . . . . . . . . . . 21
7.3 Write Locks and
locking operations (Section 6). These sections introduce the
abstractions manipulated by the WebDAV-specific HTTP methods (Section
8) Lock Tokens . . . . . . . . . . . . . . 22
7.4 Write Locks and Properties . . . . . . . . . . . . . . . 22
7.5 Avoiding Lost Updates . . . . . . . . . . . . . . . . . 22
7.6 Write Locks and Unmapped URLs . . . . . . . . . . . . . 23
7.7 Write Locks and Collections . . . . . . . . . . . . . . 25
7.8 Write Locks and the new If Request Header . . . . . . . . . 26
7.9 Write Locks and COPY/MOVE . . . . . . . . . . . . . . . 27
7.10 Refreshing Write Locks . . . . . . . . . . . . . . . . . 28
8. HTTP headers used with WebDAV methods (Section 9).

While the status codes provided by HTTP/1.1 are sufficient to
describe most error conditions encountered by WebDAV methods, there
are some errors that do not fall neatly into the existing categories.
This specification defines new status codes developed Methods for WebDAV
methods (Section 10) Distributed Authoring . . . . . . . . . . . 29
8.1 General request and describes existing HTTP status codes
(Section 11) as used in WebDAV. Since some WebDAV methods may
operate over many resources, the Multi-Status response (Section 12)
has been introduced to return status information for multiple
resources. Finally, this version handling . . . . . . . . . 29
8.1.1 Use of WebDAV introduces XML elements . . . . . . . . . . . . . . . . . . . . . 29
8.1.2 Required Bodies in Requests . . . . . . . . . . . . 29
8.1.3 Use of Location header in responses . . . . . . . . 29
8.1.4 Required Response Headers: Date . . . . . . . . . . 29
8.1.5 ETag . . . . . . . . . . . . . . . . . . . . . . . . 29
8.1.6 Including error response bodies in Section 15. . . . . . . . . . . 30
8.2 PROPFIND . . . . . . . . . . . . . . . . . . . . . . . . 31
8.2.1 Example - Retrieving Named Properties . . . . . . . 33
8.2.2 Example - Retrieving Named and Dead Properties . . . 35
8.2.3 Example - Using propname to Retrieve all Property
Names . . . . . . . . . . . . . . . . . . . . . . . 35
8.2.4 PROPFIND Request Errors . . . . . . . . . . . . . . 37

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8.3 PROPPATCH . . . . . . . . . . . . . . . . . . . . . . . 37
8.3.1 Status Codes for use with 207 (Multi-Status) . . . . 37
8.3.2 Example - PROPPATCH . . . . . . . . . . . . . . . . 39
8.4 MKCOL Method . . . . . . . . . . . . . . . . . . . . . . 40
8.4.1 MKCOL Status Codes . . . . . . . . . . . . . . . . . 40
8.4.2 Example - MKCOL . . . . . . . . . . . . . . . . . . 41
8.5 GET, HEAD for Collections . . . . . . . . . . . . . . . 41
8.6 POST for Collections . . . . . . . . . . . . . . . . . . 42
8.7 DELETE . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.7.1 DELETE for Non-Collection Resources . . . . . . . . 42
8.7.2 DELETE for Collections . . . . . . . . . . . . . . . 42
8.7.3 Example - DELETE . . . . . . . . . . . . . . . . . . 43
8.8 PUT . . . . . . . . . . . . . . . . . . . . . . . . . . 43
8.8.1 PUT for Non-Collection Resources . . . . . . . . . . 43
8.8.2 PUT for Collections . . . . . . . . . . . . . . . . 44
8.9 COPY . . . . . . . . . . . . . . . . . . . . . . . . . . 44
8.9.1 COPY for Non-collection Resources . . . . . . . . . 44
8.9.2 COPY for Properties . . . . . . . . . . . . . . . . 45
8.9.3 COPY for Collections . . . . . . . . . . . . . . . . 45
8.9.4 COPY and response
information, as well as to express metadata, so this specification
contains definitions of all XML elements used (Section 13). WebDAV
includes a few special rules on how to process XML (Section 16)
appearing in WebDAV so that it truly is extensible.

WebDAV employs the property mechanism to store information about the
current state of the resource. For example, when a lock is taken out
on a resource, a lock information property describes the current
state of the lock.

Finishing off Overwrite Header . . . . . . . . . . . 46
8.9.5 Status Codes . . . . . . . . . . . . . . . . . . . . 47
8.9.6 COPY Examples . . . . . . . . . . . . . . . . . . . 47
8.10 MOVE . . . . . . . . . . . . . . . . . . . . . . . . . . 49
8.10.1 MOVE for Properties . . . . . . . . . . . . . . . . 50
8.10.2 MOVE for Collections . . . . . . . . . . . . . . . . 50
8.10.3 MOVE and the specification are sections on what it means to be
compliant with this specification (Section 17), on
internationalization support (Section 18), Overwrite Header . . . . . . . . . . . 51
8.10.4 Status Codes . . . . . . . . . . . . . . . . . . . . 51
8.10.5 Examples . . . . . . . . . . . . . . . . . . . . . . 52
8.11 LOCK Method . . . . . . . . . . . . . . . . . . . . . . 53
8.11.1 Refreshing Locks . . . . . . . . . . . . . . . . . . 54
8.11.2 Depth and on security (Section
19). Locking . . . . . . . . . . . . . . . . . 55
8.11.3 Locking Unmapped URLs . . . . . . . . . . . . . . . 55
8.11.4 Lock Compatibility Table . . . . . . . . . . . . . . 56
8.11.5 LOCK responses . . . . . . . . . . . . . . . . . . . 56
8.11.6 Example - Simple Lock Request . . . . . . . . . . . 57
8.11.7 Example - Refreshing a Write Lock . . . . . . . . . 59
8.11.8 Example - Multi-Resource Lock Request . . . . . . . 60
8.12 UNLOCK Method . . . . . . . . . . . . . . . . . . . . . 61
8.12.1 Status Codes . . . . . . . . . . . . . . . . . . . . 61
8.12.2 Example . . . . . . . . . . . . . . . . . . . . . . 62
9. HTTP Headers for Distributed Authoring . . . . . . . . . . . 63
9.1 DAV Header . . . . . . . . . . . . . . . . . . . . . . . 63
9.2 Depth Header . . . . . . . . . . . . . . . . . . . . . . 63
9.3 Destination Header . . . . . . . . . . . . . . . . . . . 65
9.4 Force-Authentication Header . . . . . . . . . . . . . . 65
9.5 If Header . . . . . . . . . . . . . . . . . . . . . . . 65
9.5.1 No-tag-list Production . . . . . . . . . . . . . . . 66
9.5.2 Tagged-list Production . . . . . . . . . . . . . . . 67

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2. Notational Conventions

Since this document describes a set of extensions 2005

9.5.3 Not Production . . . . . . . . . . . . . . . . . . . 67
9.5.4 Matching Function . . . . . . . . . . . . . . . . . 68
9.5.5 If Header and Non-DAV Aware Proxies . . . . . . . . 69
9.6 Lock-Token Header . . . . . . . . . . . . . . . . . . . 69
9.7 Overwrite Header . . . . . . . . . . . . . . . . . . . . 69
9.8 Timeout Request Header . . . . . . . . . . . . . . . . . 69
10. Status Code Extensions to the HTTP/1.1
protocol, the augmented BNF used herein to describe protocol elements
is exactly the same as described in section 2.1 . . . . . . . . . . . . 71
10.1 102 Processing . . . . . . . . . . . . . . . . . . . . . 71
10.2 207 Multi-Status . . . . . . . . . . . . . . . . . . . . 71
10.3 422 Unprocessable Entity . . . . . . . . . . . . . . . . 71
10.4 423 Locked . . . . . . . . . . . . . . . . . . . . . . . 71
10.5 424 Failed Dependency . . . . . . . . . . . . . . . . . 72
10.6 507 Insufficient Storage . . . . . . . . . . . . . . . . 72
11. Use of RFC2616 [8],
including the rules about implied linear white-space. Since this
augmented BNF uses the basic production rules provided HTTP Status Codes . . . . . . . . . . . . . . . . . 73
11.1 301 Moved Permanently . . . . . . . . . . . . . . . . . 73
11.2 302 Found . . . . . . . . . . . . . . . . . . . . . . . 73
11.3 400 Bad Request . . . . . . . . . . . . . . . . . . . . 73
11.4 403 Forbidden . . . . . . . . . . . . . . . . . . . . . 73
11.5 409 Conflict . . . . . . . . . . . . . . . . . . . . . . 73
11.6 412 Precondition Failed . . . . . . . . . . . . . . . . 73
11.7 414 Request-URI Too Long . . . . . . . . . . . . . . . . 74
11.8 503 Service Unavailable . . . . . . . . . . . . . . . . 74
12. Multi-Status Response . . . . . . . . . . . . . . . . . . 75
12.1 Responses requiring Location in section 2.2
of RFC2616 [8], these rules apply to this document as well.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC2119 [3]. Multi-Status . . . . . . 75
13. XML Element Definitions . . . . . . . . . . . . . . . . . 77
13.1 activelock XML Element . . . . . . . . . . . . . . . . . 77
13.2 depth XML Element . . . . . . . . . . . . . . . . . . . 77
13.3 locktoken XML Element . . . . . . . . . . . . . . . . . 77
13.4 lockroot XML Element . . . . . . . . . . . . . . . . . . 78
13.5 timeout XML Element . . . . . . . . . . . . . . . . . . 78
13.6 collection XML Element . . . . . . . . . . . . . . . . . 79
13.7 href XML Element . . . . . . . . . . . . . . . . . . . . 79
13.8 lockentry XML Element . . . . . . . . . . . . . . . . . 79
13.9 lockinfo XML Element . . . . . . . . . . . . . . . . . . 80
13.10 lockscope XML Element . . . . . . . . . . . . . . . . 80
13.11 exclusive XML Element . . . . . . . . . . . . . . . . 80
13.12 shared XML Element . . . . . . . . . . . . . . . . . . 81
13.13 locktype XML Element . . . . . . . . . . . . . . . . . 81
13.14 write XML Element . . . . . . . . . . . . . . . . . . 82
13.15 multistatus XML Element . . . . . . . . . . . . . . . 82
13.16 response XML Element . . . . . . . . . . . . . . . . . 82
13.17 propstat XML Element . . . . . . . . . . . . . . . . . 83
13.18 status XML Element . . . . . . . . . . . . . . . . . . 83
13.19 responsedescription XML Element . . . . . . . . . . . 84
13.20 owner XML Element . . . . . . . . . . . . . . . . . . 84
13.21 prop XML element . . . . . . . . . . . . . . . . . . . 85
13.22 propertyupdate XML element . . . . . . . . . . . . . . 85
13.23 remove XML element . . . . . . . . . . . . . . . . . . 85

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3. Terminology

URI/URL - A Uniform Resource Identifier and Uniform Resource Locator,
respectively. These terms (and the distinction between them) are
defined in RFC2396 [6].

Collection - A resource that contains a 2005

13.24 set of URLs, which identify
and locate member resources and which meet XML element . . . . . . . . . . . . . . . . . . . 86
13.25 propfind XML Element . . . . . . . . . . . . . . . . . 86
13.26 allprop XML Element . . . . . . . . . . . . . . . . . 87
13.27 propname XML Element . . . . . . . . . . . . . . . . . 87
13.28 dead-props XML Element . . . . . . . . . . . . . . . . 87
13.29 location XML Element . . . . . . . . . . . . . . . . . 88
13.30 error XML Element . . . . . . . . . . . . . . . . . . 88
14. DAV Properties . . . . . . . . . . . . . . . . . . . . . . 89
14.1 creationdate Property . . . . . . . . . . . . . . . . . 89
14.2 displayname Property . . . . . . . . . . . . . . . . . . 90
14.3 getcontentlanguage Property . . . . . . . . . . . . . . 90
14.4 getcontentlength Property . . . . . . . . . . . . . . . 91
14.5 getcontenttype Property . . . . . . . . . . . . . . . . 91
14.6 getetag Property . . . . . . . . . . . . . . . . . . . . 92
14.7 getlastmodified Property . . . . . . . . . . . . . . . . 93
14.8 lockdiscovery Property . . . . . . . . . . . . . . . . . 94
14.8.1 Example - Retrieving the collections
requirements (Section 5).

Member URL lockdiscovery Property . . 94
14.9 resourcetype Property . . . . . . . . . . . . . . . . . 96
14.10 supportedlock Property . . . . . . . . . . . . . . . . 96
14.10.1 Example - A URL which is a member of Retrieving the set of URLs contained by
a collection.

Internal Member URL - A Member URL that is immediately relative to
the URL supportedlock Property . 98
15. Precondition/postcondition XML elements . . . . . . . . . 99
16. Instructions for Processing XML in DAV . . . . . . . . . . 102
17. DAV Compliance Classes . . . . . . . . . . . . . . . . . . 103
17.1 Class 1 . . . . . . . . . . . . . . . . . . . . . . . . 103
17.2 Class 2 . . . . . . . . . . . . . . . . . . . . . . . . 103
17.3 Class 'bis' . . . . . . . . . . . . . . . . . . . . . . 103
18. Internationalization Considerations . . . . . . . . . . . 105
19. Security Considerations . . . . . . . . . . . . . . . . . 107
19.1 Authentication of the collection (the definition Clients . . . . . . . . . . . . . . . 107
19.2 Denial of immediately relative is
given later (Section 5.2)).

Property Service . . . . . . . . . . . . . . . . . . . 107
19.3 Security through Obscurity . . . . . . . . . . . . . . . 108
19.4 Privacy Issues Connected to Locks . . . . . . . . . . . 108
19.5 Privacy Issues Connected to Properties . . . . . . . . . 108
19.6 Implications of XML External Entities . . . . . . . . . 109
19.7 Risks Connected with Lock Tokens . . . . . . . . . . . . 109
20. IANA Considerations . . . . . . . . . . . . . . . . . . . 111
21. Acknowledgements . . . . . . . . . . . . . . . . . . . . . 112
22. References . . . . . . . . . . . . . . . . . . . . . . . . 113
22.1 Normative References . . . . . . . . . . . . . . . . . . 113
22.2 Informational References . . . . . . . . . . . . . . . . 113
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 114
A. Previous Authors' Addresses . . . . . . . . . . . . . . . . 115
B. Appendices . . . . . . . . . . . . . . . . . . . . . . . . . 116
B.1 Appendix 1 - A name/value pair that contains descriptive information
about a resource.

Live Property Notes on Processing XML Elements . . . . . 116
B.1.1 Notes on Empty XML Elements . . . . . . . . . . . . 116
B.1.2 Notes on Illegal XML Processing . . . . . . . . . . 116
B.1.3 Example - A property whose semantics and syntax are enforced by
the server. For example, the live "getcontentlength" property has
its value, the length of the entity returned by a GET request,
automatically calculated by the server.

Dead Property XML Syntax Error . . . . . . . . . . . . . 116
B.1.4 Example - A property whose semantics and syntax are not
enforced by the server. The server only records the value of a dead
property; the client is responsible for maintaining the consistency
of the syntax and semantics of a dead property. Unknown XML Element . . . . . . . . . . . 117

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4. Data Model for Resource Properties

4.1 The Resource Property Model

Properties are pieces of data that describe the state of a resource.
Properties are data about data.

Properties are used 2005

B.2 Appendix 3: Notes on HTTP Client Compatibility . . . . . 118
B.3 Changes . . . . . . . . . . . . . . . . . . . . . . . . 119
B.3.1 Changes in distributed authoring environments to provide
for efficient discovery -06 . . . . . . . . . . . . . . . . . . . 119
B.3.2 Changes in -07 . . . . . . . . . . . . . . . . . . . 119
Intellectual Property and management of resources. For example, a
'subject' property might allow for Copyright Statements . . . . . . . 121

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1. Introduction

This document describes an extension to the indexing HTTP/1.1 protocol that
allows clients to perform remote web content authoring operations.
This extension provides a coherent set of all resources by
their subject, methods, headers, request
entity body formats, and an 'author' property might allow for response entity body formats that provide
operations for:

Properties: The ability to create, remove, and query information
about Web pages, such as their authors, creation dates, etc. Also,
the discovery ability to link pages of what authors have written which documents. any media type to related pages.

Collections: The DAV property model consists ability to create sets of name/value pairs. documents and to retrieve
a hierarchical membership listing (like a directory listing in a file
system).

Locking: The name of ability to keep more than one person from working on a
property identifies
document at the property's syntax and semantics, and provides
an address by same time. This prevents the "lost update problem",
in which modifications are lost as first one author then another
writes changes without merging the other author's changes.

Namespace Operations: The ability to refer instruct the server to its syntax copy and semantics.

There are two categories of properties: "live"
move Web resources.

Requirements and "dead". A live
property has its syntax rationale for these operations are described in a
companion document, "Requirements for a Distributed Authoring and semantics enforced by
Versioning Protocol for the server. Live
properties include cases where a) World Wide Web" (RFC2291) [12].

This standard does not specify the value of a property is read-
only, maintained versioning operations suggested by the server, and b) the value
RFC2291 [12]. That work was done in a separate document, "Versioning
Extensions to WebDAV" (RFC3253) [14].

The sections below provide a detailed introduction to resource
properties (Section 4), collections of resources (Section 5), and
locking operations (Section 6). These sections introduce the property is
maintained
abstractions manipulated by the client, but WebDAV-specific HTTP methods
(Section 8) and the server performs syntax checking on
submitted values. All instances of a given live property MUST comply new HTTP headers used with WebDAV methods
(Section 9).

While the definition associated with that property name. A dead
property has its syntax and semantics enforced status codes provided by HTTP/1.1 are sufficient to
describe most error conditions encountered by WebDAV methods, there
are some errors that do not fall neatly into the client; the
server merely records the value of the property verbatim.

4.2 Existing Metadata Proposals

Properties have long played an essential role in the maintenance of
large document repositories, existing categories.
This specification defines new status codes developed for WebDAV
methods (Section 10) and many current proposals contain describes existing HTTP status codes
(Section 11) as used in WebDAV. Since some
notion WebDAV methods may
operate over many resources, the Multi-Status response (Section 12)
has been introduced to return status information for multiple
resources. Finally, this version of a property, or discuss web metadata more generally. These
include PICS [20], PICS-NG, XML, Web Collections, and several
proposals on representing relationships within HTML. Work on PICS-NG WebDAV introduces XML elements

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in error response bodies in Section 15.

WebDAV uses XML [11] to marshal complicated request and Web Collections has been subsumed by the Resource Description
Framework (RDF) metadata activity of the World Wide Web Consortium.
RDF consists response
information, as well as to express metadata, so this specification
contains definitions of all XML elements used (Section 13). WebDAV
includes a network-based data model and an few special rules on how to process XML representation
of (Section 16)
appearing in WebDAV so that model.

Some proposals come from a digital library perspective. These
include the Dublin Core [RFC2413] metadata set and it truly is extensible.

Finishing off the Warwick
Framework [WF], a container architecture specification are sections on what it means for different metadata
schemas. The literature includes many examples of metadata,
including MARC [USMARC], a bibliographic metadata format,
resource to be compliant with this specification (Section 17), on
internationalization support (Section 18), and a
technical report bibliographic format employed by the Dienst system
[RFC1807]. Additionally, the proceedings from the first IEEE
Metadata conference describe many community-specific metadata sets. on security
(Section 19).

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Participants 2005

2. Notational Conventions

Since this document describes a set of extensions to the 1996 Metadata II Workshop in Warwick, UK [WF],
noted that "new metadata sets will develop as HTTP/1.1
protocol, the networked
infrastructure matures" and "different communities will propose,
design, and be responsible for different types of metadata." These
observations can be corroborated by noting that many community-
specific sets of metadata already exist, and there augmented BNF used herein to describe protocol elements
is significant
motivation for exactly the development of new forms of metadata same as many
communities increasingly make their data available in digital form,
requiring a metadata format to assist data location and cataloging.

4.3 Properties and HTTP Headers

Properties already exist, in a limited sense, described in HTTP message
headers. However, in distributed authoring environments a relatively
large number section 2.1 of properties are needed to describe RFC2616 [7],
including the state rules about implied linear white-space. Since this
augmented BNF uses the basic production rules provided in section 2.2
of a
resource, RFC2616 [7], these rules apply to this document as well.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and setting/returning them all through HTTP headers is
inefficient. Thus a mechanism is needed which allows a principal "OPTIONAL" in this
document are to
identify be interpreted as described in RFC2119 [2].

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3. Terminology

URI/URL - A Uniform Resource Identifier and Uniform Resource Locator,
respectively. These terms (and the distinction between them) are
defined in RFC2396 [5].

Collection - A resource that contains a set of properties in URLs, which identify
and locate member resources and which meet the principal collections
requirements (Section 5).

Member URL - A URL which is interested and
to set or retrieve just those properties.

4.4 XML Usage

In HTTP/1.1, method parameter information was exclusively encoded in
HTTP headers. Unlike HTTP/1.1, WebDAV encodes method parameter
information either in an XML [11] request entity body, or in an HTTP
header. The use a member of XML to encode method parameters was motivated by the ability to add extra XML elements to existing structures,
providing extensibility; and set of URLs contained by XML's ability
a collection.

Internal Member URL - A Member URL that is immediately relative to encode information
in ISO 10646 character sets, providing internationalization support.

In addition to encoding method parameters, XML is used in WebDAV to
encode
the responses from methods, providing URL of the extensibility and
internationalization advantages collection (the definition of XML for method output, as well as
input.

The XML namespace extension [10] immediately relative is also used in this specification
in order to allow for new XML elements to be added without fear of
colliding with other element names. Although WebDAV request
given later (Section 5.2)).

Property - A name/value pair that contains descriptive information
about a resource.

Live Property - A property whose semantics and
response bodies can be extended by arbitrary XML elements, which can
be ignored syntax are enforced by
the message recipient, an XML element in server. For example, the "DAV:"
namespace SHOULD NOT be used in live "getcontentlength" property has
its value, the request or response body unless
that XML element is explicitly defined in an IETF RFC reviewed length of the entity returned by a
WebDAV working group.

Note that "DAV:" is a scheme name defined solely to provide GET request,
automatically calculated by the server.

Dead Property - A property whose semantics and syntax are not
enforced by the server. The server only records the value of a
namespace dead
property; the client is responsible for WebDAV XML elements maintaining the consistency
of the syntax and property names. This practice
is discouraged in part because registration semantics of new scheme names a dead property.

Principal - A "principal" is
difficult. "DAV:" was defined as the WebDAV namespace before a distinct human or computational actor
that initiates access to network resources.

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standard best practices emerged, and this namespace is kept and still
used because of significant existing deployments, but this should not
be emulated.

4.5 Property Values 2005

4. Data Model for Resource Properties

4.1 The value Resource Property Model

Properties are pieces of a property is always a (well-formed) XML fragment.

XML has been chosen because it is a flexible, self-describing,
structured data format that supports rich schema definitions, and
because of its support for multiple character sets. XML's self-
describing nature allows any property's value to be extended by
adding new elements. Older clients will not break when they
encounter extensions because they will still have describe the state of a resource.
Properties are data specified about data.

Properties are used in the original schema and will ignore elements they do not
understand. XML's support for multiple character sets allows any
human-readable property distributed authoring environments to be encoded provide
for efficient discovery and read in management of resources. For example, a character set
familiar to the user. XML's support
'subject' property might allow for multiple human languages,
using the "xml:lang" attribute, handles cases where the same
character set is employed indexing of all resources by multiple human languages. Note that
xml:lang scope is recursive, so a xml:lang attribute on any element
containing a
their subject, and an 'author' property name element applies to might allow for the discovery
of what authors have written which documents.

The DAV property value
unless it has been overridden by model consists of name/value pairs. The name of a more locally scoped attribute.

A
property is always represented in XML with an XML element
consisting of identifies the property name. The simplest example is an empty
property, property's syntax and semantics, and provides
an address by which is different from a property that does not exist.

<R:title xmlns:R="http://www.example.com/ns/"></R:title>

The value to refer to its syntax and semantics.

There are two categories of a property appears inside the properties: "live" and "dead". A live
property name element.
The value may be any kind of well-formed XML content, including both
text-only has its syntax and mixed content. When semantics enforced by the server. Live
properties include cases where a) the property value contains
further XML elements, namespaces that are in scope for that part of
the XML document apply within the a property value as well, is read-
only, maintained by the server, and MUST be
preserved in server storage for retransmission later. Namespace
prefixes need not be preserved due to b) the rules value of prefix declaration
in XML.

Attributes on the property name element may convey information about is
maintained by the property, client, but are not considered part of the value. However,
when language information appears in the 'xml:lang' attribute server performs syntax checking on the
submitted values. All instances of a given live property name element, the language information MUST be preserved in
server storage for retransmission later.

The XML attribute xml:space MUST NOT be used to change white space
handling. White space in property values is significant.

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4.6 Property Names

A property name is a universally unique identifier that is comply
with the definition associated with a schema that provides information about the property name. A dead
property has its syntax and semantics of enforced by the property.

Because a property's name is universally unique, clients can depend
upon consistent behavior for a particular property across multiple
resources, on the same and across different servers, so long as that
property is "live" on client; the resources in question, and
server merely records the
implementation value of the live property is faithful to its definition.

The XML namespace mechanism, which is based on URIs [6], is used to
name properties because it prevents namespace collisions and provides
for varying degrees of administrative control.

The property namespace is flat; that is, no hierarchy of properties
is explicitly recognized. Thus, if a property A verbatim.

4.2 Properties and HTTP Headers

Properties already exist, in a property A/B
exist on limited sense, in HTTP message
headers. However, in distributed authoring environments a resource, there is no recognition relatively
large number of any relationship
between the two properties. It is expected that a separate
specification will eventually be produced which will address issues
relating to hierarchical properties.

Finally, it is not possible properties are needed to define the same property twice on a
single resource, as this would cause a collision in describe the resource's
property namespace.

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5. Collections of Web Resources

This section provides a description state of a new type of Web
resource,
the collection, and discusses its interactions with the setting/returning them all through HTTP URL
namespace. The purpose of headers is
inefficient. Thus a collection resource mechanism is needed which allows a principal to model
collection-like objects (e.g., file system directories) within
identify a
server's namespace.

All DAV compliant resources MUST support set of properties in which the HTTP URL namespace model
specified herein.

5.1 HTTP URL Namespace Model

The HTTP URL namespace is a hierarchical namespace where the
hierarchy is delimited with the "/" character.

An HTTP URL namespace principal is said interested and
to be consistent if it meets the
following conditions: for every URL set or retrieve just those properties.

4.3 XML Usage

In HTTP/1.1, method parameter information was exclusively encoded in the
HTTP hierarchy there
exists a collection that contains that URL as headers. Unlike HTTP/1.1, WebDAV encodes method parameter
information either in an internal member.
The root, XML [11] request entity body, or top-level collection in an HTTP
header. The use of XML to encode method parameters was motivated by
the namespace under
consideration ability to add extra XML elements to existing structures,
providing extensibility; and by XML's ability to encode information
in ISO 10646 character sets, providing internationalization support.

In addition to encoding method parameters, XML is exempt from the previous rule.

Neither HTTP/1.1 nor used in WebDAV require that to

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encode the entire HTTP URL
namespace be consistent. However, certain WebDAV methods are
prohibited responses from producing results that cause methods, providing the extensibility and
internationalization advantages of XML for method output, as well as
input.

The XML namespace
inconsistencies.

Although implicit extension [10] is also used in RFC2616 [8] this specification
in order to allow for new XML elements to be added without fear of
colliding with other element names. Although WebDAV request and RFC2396 [6], any resource,
including collection resources, MAY
response bodies can be identified extended by more than one
URI. For example, a resource could arbitrary XML elements, which can
be identified ignored by multiple HTTP
URLs.

5.2 Collection Resources

A collection the message recipient, an XML element in the "DAV:"
namespace SHOULD NOT be used in the request or response body unless
that XML element is a resource whose state consists of at least a list of
internal member URLs and a set of properties, but which may have
additional state such as entity bodies returned explicitly defined in an IETF RFC reviewed by GET. An internal
member URL MUST be immediately relative to a base URL of the
collection. That is, the internal member URL
WebDAV working group.

Note that "DAV:" is equal a scheme name defined solely to provide a
containing collection's URL plus an additional segment for non-
collection resources, or additional segment plus trailing slash "/"
namespace for collection resources, where segment WebDAV XML elements and property names. This practice
is defined discouraged in section 3.3 part because registration of
RFC2396 [6].

Any given internal member URL MUST only belong to the collection
once, i.e., it new scheme names is illegal to have multiple instances of the same URL
in a collection. Properties
difficult. "DAV:" was defined on collections behave exactly as
do properties on non-collection resources.

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For all the WebDAV compliant resources A and B, identified by URLs U namespace before
standard best practices emerged, and
V, for which U this namespace is immediately relative to V, B MUST kept and still
used because of significant existing deployments, but this should not
be a collection
that has U as an internal member URL. So, if the resource with URL
http://example.com/bar/blah emulated.

4.4 Property Values

The value of a property is WebDAV compliant and if the resource
with URL http://example.com/bar/ always a (well-formed) XML fragment.

XML has been chosen because it is WebDAV compliant then the
resource with URL http://example.com/bar/ must be a collection flexible, self-describing,
structured data format that supports rich schema definitions, and
must contain URL http://example.com/bar/blah as an internal member.

Collection resources MAY list the URLs
because of non-WebDAV compliant
children in the HTTP URL namespace hierarchy as internal members but
are not required its support for multiple character sets. XML's self-
describing nature allows any property's value to do so. For example, if the resource with URL
http://example.com/bar/blah is not WebDAV compliant and the URL
http://example.com/bar/ identifies a collection then URL http://
example.com/bar/blah may or may not be an internal member of extended by
adding new elements. Older clients will not break when they
encounter extensions because they will still have the
collection with URL http://example.com/bar/.

If a WebDAV compliant resource has no WebDAV compliant children data specified
in the HTTP URL namespace hierarchy then the WebDAV compliant resource
is original schema and will ignore elements they do not required
understand. XML's support for multiple character sets allows any
human-readable property to be encoded and read in a collection.

There is a standing convention that when a collection is referred character set
familiar to
by its name without a trailing slash, the server MAY handle user. XML's support for multiple human languages,
using the
request as if "xml:lang" attribute, handles cases where the trailing slash were present. In this case it
SHOULD return a Content-Location header in the response, pointing to
the URL ending with the "/". For example, if a client invokes same
character set is employed by multiple human languages. Note that
xml:lang scope is recursive, so a
method on http://example.bar/blah (no trailing slash), the server may
respond as if the operation were invoked xml:lang attribute on http://example.com/blah/
(trailing slash), and should return any element
containing a Content-Location header with property name element applies to the property value http://example.bar/blah/. Wherever a server produces a URL
referring to
unless it has been overridden by a collection, the server MUST include the trailing
slash. In general clients SHOULD use the "/" form of collection
names. more locally scoped attribute.

A resource MAY be a collection but not be WebDAV compliant. That is,
the resource may comply property is always represented in XML with all an XML element
consisting of the rules set out in this
specification regarding how a collection property name. The simplest example is to behave without
necessarily supporting all methods that a WebDAV compliant resource an empty
property, which is required to support. In such different from a case the resource may return the
DAV:resourcetype property with the that does not exist.

<R:title xmlns:R="http://www.example.com/ns/"></R:title>

The value DAV:collection but MUST NOT
return of a DAV header containing the value "1" on an OPTIONS response.

Clients MUST be able to support the case where WebDAV resources are
contained property appears inside non-WebDAV resources. For example, if a OPTIONS
response from "http://example.com/servlet/dav/collection" indicates
WebDAV support, the client cannot assume that "http://example.com/
servlet/dav/" or its parent necessarily are WebDAV collections. property name element.

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5.3 Source Resources and Output Resources

For many resources, the entity returned by a GET method exactly
matches the persistent state of the resource, for example, a GIF file
stored on a disk. For this simple case, the URL at which a resource
is accessed is identical to the URL at which the source (the
persistent state) 2005

The value may be any kind of well-formed XML content, including both
text-only and mixed content. When the resource is accessed. This is also the case
for HTML source files property value contains
further XML elements, namespaces that are not processed by in scope for that part of
the server prior to
transmission.

However, XML document apply within the server can sometimes process HTML resources before they
are transmitted property value as a return entity body. For example, a server-
side-include directive within an HTML file might instruct a well, and MUST be
preserved in server storage for retransmission later. Namespace
prefixes need not be preserved due to
replace the directive with another value, such as rules of prefix declaration
in XML.

Attributes on the current date.
In this case, what is returned by GET (HTML plus date) differs from property name element may convey information about
the persistent state property, but are not considered part of the resource (HTML plus directive).
Typically there is no way to access the HTML resource containing value. However,
when language information appears in the
unprocessed directive.

Sometimes 'xml:lang' attribute on the entity returned by GET is
property name element, the output of a data-
producing process language information MUST be preserved in
server storage for retransmission later. Note that is described by a property only
has one or more source resources
(that may value, in one language (or language MAY be left undefined),
not even have a location multiple values in the URI namespace). A single
data-producing process may dynamically generate the state of different languages or a
potentially large number of output resources. An example of this single value in
multiple languages.

The XML attribute xml:space MUST NOT be used to change white space
handling. White space in property values is significant.

4.5 Property Names

A property name is a CGI script universally unique identifier that describes is associated
with a "finger" gateway process schema that maps part
of provides information about the namespace syntax and
semantics of the property.

Because a server into finger requests, such as http://
finger.example.com/finger_gateway/user@host.

Although this problem would usefully be solved, interoperable WebDAV
implementations have been widely deployed without actually solving
this problem. Thus, property's name is universally unique, clients can depend
upon consistent behavior for a particular property across multiple
resources, on the source vs. output problem same and across different servers, so long as that
property is not solved "live" on the resources in
this specification, question, and has been deferred the
implementation of the live property is faithful to a separate document.

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6. Locking its definition.

The ability XML namespace mechanism, which is based on URIs [5], is used to lock a resource
name properties because it prevents namespace collisions and provides a mechanism
for serializing
access to varying degrees of administrative control.

The property namespace is flat; that resource. Using is, no hierarchy of properties
is explicitly recognized. Thus, if a lock, an authoring client can
provide property A and a reasonable guarantee that another principal will not modify property A/B
exist on a resource while it resource, there is being edited. In this way, a client can
prevent the "lost update" problem.

This no recognition of any relationship
between the two properties. It is expected that a separate
specification allows locks will eventually be produced which will address issues
relating to vary over two client-specified
parameters, hierarchical properties.

Finally, it is not possible to define the number of principals involved (exclusive vs. shared) same property twice on a
single resource, as this would cause a collision in the resource's
property namespace.

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4.6 Source Resources and Output Resources

Some HTTP resources are dynamically generated by the type server. For
these resources, there presumably exists source code somewhere
governing how that resource is generated. The relationship of access source
files to output HTTP resources may be granted. This document defines locking
for only one access type, write. However, the syntax is extensible,
and permits the eventual specification of locking for other access
types.

6.1 Exclusive Vs. Shared Locks

The most basic form of lock is an exclusive lock. Only to one, one exclusive
lock may exist on any resource, to many, many
to one or many to many. There is no mechanism in HTTP to determine
whether it a resource is directly even dynamic, let alone where its source files
exist or indirectly
locked (Section 7.5). Exclusive locks avoid having how to merge results, author them. Although this problem would usefully be
solved, interoperable WebDAV implementations have been widely
deployed without requiring any coordination other than the methods described
in actually solving this specification.

However, there are times when problem, by dealing only with
static resources. Thus, the goal of a lock source vs. output problem is not solved
in this specification and has been deferred to exclude
others from exercising an access right but rather to provide a
mechanism for principals to indicate that they intend to exercise
their access rights. Shared locks are provided for this case. A
shared lock allows multiple principals to receive separate document.

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5. Collections of Web Resources

This section provides a lock. Hence any
principal description of a new type of Web resource,
the collection, and discusses its interactions with appropriate access can use the lock.

With shared locks there are two trust sets that affect a resource. HTTP URL
namespace. The first trust set purpose of a collection resource is created by access permissions. Principals who
are trusted, for example, may have permission to write to the
resource. Among those who have access permission to write to the
resource, the set of principals who have taken out model
collection-like objects (e.g., file system directories) within a shared lock also
must trust each other, creating
server's namespace.

All DAV compliant resources MUST support the HTTP URL namespace model
specified herein.

5.1 HTTP URL Namespace Model

The HTTP URL namespace is a (typically) smaller trust set
within hierarchical namespace where the access permission write set.

Starting
hierarchy is delimited with every possible principal on the Internet, "/" character.

An HTTP URL namespace is said to be consistent if it meets the
following conditions: for every URL in most
situations the vast majority of these principals will not have write
access to HTTP hierarchy there
exists a given resource. Of the small number who do have write
access, some principals may decide to guarantee their edits are free collection that contains that URL as an internal member.
The root, or top-level collection of the namespace under
consideration is exempt from overwrite conflicts the previous rule. The top-level
collection of the namespace under consideration is not necessarily
the collection identified by using exclusive write locks. Others the absolute path '/', it may be
identified by one or more path segments (e.g. /servlets/webdav/...)

Neither HTTP/1.1 nor WebDAV require that the entire HTTP URL
namespace be consistent -- a WebDAV-compatible resource may
decide they trust their collaborators will not overwrite their work
(the potential set have
a parent collection. However, certain WebDAV methods are prohibited
from producing results that cause namespace inconsistencies.

Although implicit in RFC2616 [7] and RFC2396 [5], any resource,
including collection resources, MAY be identified by more than one
URI. For example, a resource could be identified by multiple HTTP
URLs.

5.2 Collection Resources

A collection is a resource whose state consists of collaborators being the set at least a list of principals who
have write permission)
internal member URLs and use a shared lock, set of properties, but which informs their
collaborators that a principal may have
additional state such as entity bodies returned by GET. An internal
member URL MUST be working on immediately relative to a base URL of the resource.
collection. That is, the internal member URL is equal to a
containing collection's URL plus an additional segment for non-
collection resources, or additional segment plus trailing slash "/"
for collection resources, where segment is defined in section 3.3 of
RFC2396 [5].

Any given internal member URL MUST only belong to the collection

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The WebDAV extensions to HTTP do not need to provide all of the
communications paths necessary for principals 2005

once, i.e., it is illegal to coordinate their
activities. When using shared locks, principals may use any out have multiple instances of
band communication channel to coordinate their work (e.g., face-to-
face interaction, written notes, post-it notes on the screen,
telephone conversation, Email, etc.) The intent of same URL
in a shared lock collection. Properties defined on collections behave exactly as
do properties on non-collection resources.

For all WebDAV compliant resources A and B, identified by URLs U and
V, for which U is immediately relative to let collaborators know who else may V, B MUST be working on a resource.

Shared locks are included because experience from web distributed
authoring systems has indicated collection
that exclusive locks are often too
rigid. An exclusive lock is used to enforce a particular editing
process: take out has U as an exclusive lock, read the resource, perform
edits, write internal member URL. So, if the resource, release resource with URL
http://example.com/bar/blah is WebDAV compliant and if the lock. This editing process
has resource
with URL http://example.com/bar/ is WebDAV compliant then the problem that locks are not always properly released, for
example when a program crashes, or when a lock owner leaves without
unlocking
resource with URL http://example.com/bar/ must be a resource. While both timeouts collection and administrative action
can be used to remove
must contain URL http://example.com/bar/blah as an offending lock, neither mechanism may be
available when needed; the timeout may be long or internal member.

Collection resources MAY list the administrator
may not be available.

6.2 Required Support

A WebDAV URLs of non-WebDAV compliant resource is
children in the HTTP URL namespace hierarchy as internal members but
are not required to support locking in any
form. If do so. For example, if the resource does support locking it may choose to support
any combination of exclusive and shared locks for any access types.

The reason for this flexibility with URL
http://example.com/bar/blah is that locking policy strikes to not WebDAV compliant and the
very heart URL
http://example.com/bar/ identifies a collection then URL
http://example.com/bar/blah may or may not be an internal member of
the collection with URL http://example.com/bar/.

If a WebDAV compliant resource management and versioning systems employed
by various storage repositories. These repositories require control
over what sort of locking will be made available. For example, some
repositories only support shared write locks while others only
provide support for exclusive write locks while yet others use has no
locking at all. As each system is sufficiently different to merit
exclusion of certain locking features, this specification leaves
locking as WebDAV compliant children in
the sole axis of negotiation within WebDAV.

6.3 Lock Tokens

A lock token HTTP URL namespace hierarchy then the WebDAV compliant resource
is not required to be a type of state token, represented as collection.

There is a URI, which
identifies standing convention that when a particular lock. A lock token collection is returned in the Lock-
Token header in the response referred to
by its name without a successful LOCK operation. The
lock token also appears in trailing slash, the value of server MAY handle the lockdiscovery property,
request as if the value of which is returned trailing slash were present. In this case it
SHOULD return a Content-Location header in the body of the response response, pointing to a
successful LOCK operation (this property also includes
the tokens of
other current locks URL ending with the "/". For example, if a client invokes a
method on http://example.bar/blah (no trailing slash), the resource). Finally, server may
respond as if the lockdiscovery
property can be queried using PROPFIND operation were invoked on http://example.com/blah/
(trailing slash), and should return a Content-Location header with
the token can value http://example.bar/blah/. Wherever a server produces a URL
referring to a collection, the server MUST include the trailing
slash. In general clients SHOULD use the "/" form of collection
names.

Clients MUST be
discovered able to support the case where WebDAV resources are
contained inside non-WebDAV resources. For example, if a OPTIONS
response from "http://example.com/servlet/dav/collection" indicates
WebDAV support, the client cannot assume that way. Each lock has only one unique lock token.
"http://example.com/servlet/dav/" or its parent necessarily are
WebDAV collections.

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Lock token URIs MUST be unique across all resources for all time.
This uniqueness constraint allows lock tokens to be submitted across
resources and servers without fear of confusion.

This specification provides a lock token URI scheme called
opaquelocktoken that meets the uniqueness requirements. However
resources are free to return any URI scheme so long as it meets the
uniqueness requirements. 2005

6. Locking

The IETF recommends using registered URI
schemes ability to ensure uniqueness.

Having a lock token a resource provides no special a mechanism for serializing
access rights. Anyone to that resource. Using a lock, an authoring client can
find out anyone else's lock token by performing lock discovery.
Locks MUST be enforced based upon whatever authentication mechanism
provide a reasonable guarantee that another principal will not modify
a resource while it is used by being edited. In this way, a client can
prevent the server, not based on "lost update" problem.

This specification allows locks to vary over two client-specified
parameters, the secrecy number of principals involved (exclusive vs. shared)
and the token values.

6.4 opaquelocktoken Lock Token URI Scheme

The opaquelocktoken URI scheme is designed type of access to be unique across all
resources granted. This document defines locking
for all time. Due to this uniqueness quality, a client may
submit an opaque only one access type, write. However, the syntax is extensible,
and permits the eventual specification of locking for other access
types.

6.1 Exclusive Vs. Shared Locks

The most basic form of lock token in is an If header exclusive lock. Only one exclusive
lock may exist on a resource any resource, whether it is directly or indirectly
locked (Section 7.7). Exclusive locks avoid having to merge results,
without requiring any coordination other than the one that returned it.

In order to guarantee uniqueness across all resources for all time
the opaquelocktoken requires the use of the Universal Unique
Identifier (UUID) mechanism, as methods described
in ISO-11578 [12].

Opaquelocktoken generators, however, have a choice this specification.

However, there are times when the goal of how they create
these tokens. They can either generate a new UUID for every lock
token they create or they can create a single UUID and then add
extension characters. If the second method is selected then the
program generating the extensions MUST guarantee that the same
extension will never be used twice with the associated UUID.

OpaqueLockToken-URI = "opaquelocktoken:" UUID [Extension] ; The UUID
production is the string representation of a UUID, as defined in
ISO-11578 [12]. Note that white space (LWS) is not allowed between
elements of this production.

Extension = path ; path is defined in section 3.3 of RFC2396 [6]

6.5 Lock Capability Discovery

Since server lock support is optional, a client trying to lock a
resource on exclude
others from exercising an access right but rather to provide a server can either try the lock and hope
mechanism for the best,
or perform some form of discovery principals to determine what lock capabilities
the server supports. This is known as lock capability discovery. indicate that they intend to exercise
their access rights. Shared locks are provided for this case. A
client can determine what
shared lock types the server supports by
retrieving the supportedlock property.

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Any DAV compliant resource that supports the LOCK method MUST support
the supportedlock property.

6.6 Active Lock Discovery

If another allows multiple principals to receive a lock. Hence any
principal with appropriate access can use the lock.

With shared locks a resource there are two trust sets that affect a principal wishes to
access, it resource.
The first trust set is useful created by access permissions. Principals who
are trusted, for the second principal example, may have permission to be able write to find out the
resource. Among those who have access permission to write to the first principal is. For this purpose
resource, the lockdiscovery
property is provided. This property lists all outstanding locks,
describes their type, and where available, provides their set of principals who have taken out a shared lock token.

Any DAV compliant resource that supports also
must trust each other, creating a (typically) smaller trust set
within the LOCK method MUST support access permission write set.

Starting with every possible principal on the lockdiscovery property.

6.7 Avoiding Lost Updates

Although Internet, in most
situations the locking mechanisms specified here provide vast majority of these principals will not have write
access to a given resource. Of the small number who do have write
access, some help in
preventing lost updates, they cannot principals may decide to guarantee that updates their edits are free
from overwrite conflicts by using exclusive write locks. Others may
decide they trust their collaborators will
never be lost. Consider not overwrite their work
(the potential set of collaborators being the following scenario:

Two clients A set of principals who
have write permission) and B are interested in editing the resource
'index.html'. Client A is an HTTP client rather than use a shared lock, which informs their
collaborators that a principal may be working on the resource.

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The WebDAV
client, and so does extensions to HTTP do not know how need to perform locking.

Client A doesn't lock the document, but does a GET and begins
editing.

Client B does LOCK, performs a GET and begins editing.

Client B finishes editing, performs a PUT, then an UNLOCK.

Client A performs a PUT, overwriting and losing provide all of B's changes.

There are several reasons why the WebDAV protocol itself cannot
prevent this situation. First, it cannot force all clients
communications paths necessary for principals to coordinate their
activities. When using shared locks, principals may use
locking because it must be compatible with HTTP clients that do not
comprehend locking. Second, it cannot require servers to support
locking because any out of
band communication channel to coordinate their work (e.g., face-to-
face interaction, written notes, post-it notes on the variety of repository implementations, some screen,
telephone conversation, Email, etc.) The intent of
which rely on reservations and merging rather than a shared lock is
to let collaborators know who else may be working on locking.
Finally, being stateless, it cannot enforce a sequence of operations
like LOCK / GET / PUT / UNLOCK.

WebDAV servers resource.

Shared locks are included because experience from web distributed
authoring systems has indicated that support locking can reduce exclusive locks are often too
rigid. An exclusive lock is used to enforce a particular editing
process: take out an exclusive lock, read the likelihood resource, perform
edits, write the resource, release the lock. This editing process
has the problem that
clients will accidentally overwrite each other's changes by requiring
clients to locks are not always properly released, for
example when a program crashes, or when a lock resources before modifying them. Such servers would
effectively prevent HTTP 1.0 owner leaves without
unlocking a resource. While both timeouts and HTTP 1.1 clients from modifying
resources.

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WebDAV clients administrative action
can be good citizens by using a lock / retrieve /
write /unlock sequence of operations (at least by default) whenever
they interact with a WebDAV server that supports locking.

HTTP 1.1 clients can be good citizens, avoiding overwriting other
clients' changes, by using entity tags in If-Match headers with any
requests that would modify resources.

Information managers may attempt used to prevent overwrites by
implementing client-side procedures requiring locking before
modifying WebDAV resources.

6.8 Locks and Multiple Bindings

A resource remove an offending lock, neither mechanism may be made
available through more than one URI. However
locks apply to resources, not URIs. Therefore a LOCK request on a
resource MUST NOT succeed if can not be honored by all when needed; the URIs
through which timeout may be long or the administrator
may not be available.

6.2 Required Support

A WebDAV compliant resource is addressable.

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7. Write Lock

This section describes the semantics specific not required to support locking in any
form. If the write lock type.
The write lock is a specific instance resource does support locking it may choose to support
any combination of a lock type, exclusive and is the only
lock type described in this specification.

Write shared locks prevent unauthorized changes for any access types.

The reason for this flexibility is that locking policy strikes to resources. In general
terms, changes affected by write locks include changes to:

o the content
very heart of the resource
o any dead property management and versioning systems employed
by various storage repositories. These repositories require control
over what sort of the resource
o any live property defined to locking will be lockable (all properties defined
in made available. For example, some
repositories only support shared write locks while others only
provide support for exclusive write locks while yet others use no
locking at all. As each system is sufficiently different to merit
exclusion of certain locking features, this specification are lockable)
o leaves
locking as the direct membership sole axis of the resource, if it negotiation within WebDAV.

6.3 Lock Tokens

A lock token is a collection
o the URL/location type of state token, represented as a resource

The next few sections describe in more specific terms how write locks
interact with various operations.

7.1 Methods Restricted by Write Locks

A write lock MUST prevent URI, which
identifies a principal without the particular lock. A lock from
successfully executing a PUT, POST, PROPPATCH, LOCK, UNLOCK, MOVE,
DELETE, or MKCOL on token is returned in the locked resource. All other current methods,
GET Lock-
Token header in particular, function independently of the lock.

Note, however, that as new methods are created it will be necessary response to specify how they interact with a write lock.

7.2 Write Locks and Lock Tokens

A successful request for an exclusive or shared write LOCK operation. The
lock MUST
result token also appears in the generation value of a unique lock token associated with the
requesting principal. Thus if five principals have a shared write
lock on lockdiscovery property,
the same resource there will be five lock tokens, one for
each principal.

7.3 Write Locks and Properties

While those without a write lock may not alter a property on a
resource it value of which is still possible for returned in the values body of live properties to
change, even while locked, due the response to a
successful LOCK operation (this property also includes the requirements tokens of their schemas.
Only dead properties and live properties defined to respect
other current locks are
guaranteed not to change while write locked.

7.4 Write Locks on the resource). Finally, the lockdiscovery
property can be queried using PROPFIND and Unmapped URLs

It is possible to the token can be
discovered that way. Each lock an unmapped URL in order to has only one unique lock the name for token.

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use. 2005

Lock token URIs MUST be unique across all resources for all time.
This is a simple way uniqueness constraint allows lock tokens to avoid the lost-update problem on the
creation be submitted across
resources and servers without fear of confusion.

This specification provides a new resource (another way is to use If-None-Match
header specified in HTTP 1.1). It has lock token URI scheme called
opaquelocktoken that meets the side benefit of locking uniqueness requirements. However
resources are free to return any URI scheme so long as it meets the new resource immediately for
uniqueness requirements. According to current IETF best practices,
implementations SHOULD use of the creator.

The lost-update problem is not an issue for collections because MKCOL
can only be used registered URI schemes to create ensure
uniqueness.

Submitting a collection, not to overwrite an existing
collection. In order to immediately lock a collection upon creation,
clients may attempt token does not confer full privilege to pipeline use the MKCOL and LOCK requests together.

A
lock request to an unmapped URL SHOULD result in token or modify the creation of an locked resource with empty content. A subsequent PUT request with
the correct resource. Anyone can find out anyone
else's lock token SHOULD normally succeed, and this new request
provides the content, content-type, content-language by performing lock discovery. Write access and
other
information as appropriate.

In this situation, a WebDAV server that was implemented from RFC2518
MAY create "lock-null" resources which are special and unusual
resources. Historically, a lock-null resource:

o Responds with a 404 privileges MUST be enforced through normal privilege or 405 to any DAV method except for PUT,
MKCOL, OPTIONS, PROPFIND, LOCK, UNLOCK.
o Appears as a member
authentication mechanisms, not based on the slight obscurity of its parent collection.
o Disappears (URI becomes unmapped) if its lock goes away before it
is converted to a regular resource. (This must also happen if it
is renamed or moved, or if any parent collection is renamed or
moved, because locks
token values.

Since lock tokens are tied to URLs).
o May be turned into unique, a regular resource when client MAY submit a PUT request to lock token in an
If header on a resource other than the
URL is successful. Ceases one that returned it.

6.4 Lock Token URI Schemes

In order to be a lock-null resource.
o May be turned into a collection when guarantee uniqueness across all resources for all time a MKCOL request
server MAY use the Universal Unique Identifier (UUID) [9] mechanism
to generate a lock token:

urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf6

The 'opaquelocktoken' URI scheme extends the URL is
successful. Ceases UUID mechanism slightly
while still guaranteeing the lock token to be a lock-null resource.
o Has defined values unique across all
resources for lockdiscovery and supportedlock properties.

However, interoperability and compliance problems have been found
with lock-null resources. Therefore, they are deprecated. WebDAV
servers SHOULD create regular locked empty resources, which are and
behave in every way as normal resources. A locked empty resource:

o Can be read, deleted, moved, copied, and in all ways behave as a
regular resource, not time. With the 'opaquelocktoken' scheme, the
server MAY reuse a lock-null resource.
o Appears as UUID with extension characters added. If the
server does this then the algorithm generating the extensions MUST
guarantee that the same extension will never be used twice with the
associated UUID.

OpaqueLockToken-URI = "opaquelocktoken:" UUID [Extension] ; The UUID
production is the string representation of a member UUID. Note that white
space (LWS) is not allowed between elements of its parent collection.
o SHOULD NOT disappear when its this production.

Extension = path ; path is defined in section 3.3 of RFC2396 [5]

6.5 Lock Capability Discovery

Since server lock goes away (clients must
therefore be responsible for cleaning up their own mess, as with
any other operation)
o SHOULD default support is optional, a client trying to having no content type.
o MAY NOT have values lock a
resource on a server can either try the lock and hope for properties like getcontentlanguage which
haven't been specified yet by the client. best,
or perform some form of discovery to determine what lock capabilities

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o May have content added with a PUT request. MUST be able to change
content type.
o MUST NOT be turned into a collection. A MKCOL request must fail 2005

the server supports. This is known as it would to any existing resource.
o MUST have defined values for lockdiscovery and lock capability discovery. A
client can determine what lock types the server supports by
retrieving the supportedlock
properties.
o The response MUST indicate that a property.

Any DAV compliant resource was created, by use of that supports the "201 Created" response code (a LOCK request to an existing
resource instead will result in 200 OK). The body must still
include method MUST support
the lockdiscovery property, as with supportedlock property.

6.6 Active Lock Discovery

If another principal locks a LOCK request resource that a principal wishes to an
existing resource.

The client
access, it is expected useful for the second principal to update be able to find out
who the locked empty resource shortly
after locking it, using PUT first principal is. For this purpose the lockdiscovery
property is provided. This property lists all outstanding locks,
describes their type, and possibly PROPPATCH. When where available, provides their lock token.

Any DAV compliant resource that supports the client
uses PUT LOCK method MUST support
the lockdiscovery property.

6.7 Locks and Multiple Bindings

A resource may be made available through more than one URI. However
locks apply to overwrite resources, not URIs. Therefore a LOCK request on a locked empty
resource the client MUST supply
a Content-Type NOT succeed if any is known. If can not be honored by all the client supplies a Content-
Type value URIs
through which the server MUST set that value (this requirement actually
applies to any resource that is overwritten but is particularly
necessary for locked empty resources which are initially created with
no Content-Type.

Clients can easily interoperate both with servers that support the
deprecated lock-null resources and servers that support simpler
locked empty resources by only attempting PUT after a LOCK to an
unmapped URL, not MKCOL or GET.

7.5 addressable.

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7. Write Locks Lock

This section describes the semantics specific to the write lock type.
The write lock is a specific instance of a lock type, and Collections

A is the only
lock type described in this specification.

An exclusive write lock on will prevent parallel changes to a collection, whether created resource
by a "Depth: 0" or
"Depth: infinity" any principal other than the write lock request, prevents holder. In general terms,
changes affected by write locks include changes to:

o the addition or removal content of
member URLs the resource

o any dead property of the collection by non-lock owners.

A zero-depth lock on a collection affects changes resource

o any live property defined to be lockable (all properties defined
in this specification are lockable)

o the direct membership of that collection. When a principal issues the resource, if it is a PUT or POST
request to create collection

o the URL/location of a new resource

The next few sections describe in a more specific terms how write locked collection, or
issues a DELETE to an existing internal member URL locks
interact with various operations.

7.1 Lock Owner

The creator of a write locked
collection, this request MUST fail if the principal does not provide
the correct lock token for is the locked collection.

In addition, a depth-infinity lock affects all write operations to
all descendents of the locked collection. With a depth-infinity
lock, owner. The server MUST restrict
the root usage of the lock is directly locked, and all token to the lock owner (both for shared and
exclusive locks -- for multi-user shared lock cases, each
authenticated principal MUST obtain its
descendants are indirectly locked.

o Any new own shared lock).

The server MAY allow privileged users other than the lock owner to
destroy a lock (for example, the resource added owner or an administrator)
as a descendent special case of lock usage.

If an anonymous user requests a depth-infinity locked
collection becomes indirectly locked.
o Any indirectly locked lock, the server MAY refuse the
request.

7.2 Methods Restricted by Write Locks

A server MUST reject any write request that alters a write-locked
resource moved out unless a valid lock token is provided. The write operations
defined in HTTP and WebDAV are PUT, POST, PROPPATCH, LOCK, UNLOCK,
MOVE, COPY (for the destination resource), DELETE, and MKCOL. All
other HTTP/WebDAV methods, GET in particular, function independently
of the locked collection
into an unlocked collection is thereafter unlocked. lock. A shared write lock prevents the same operations,
however it also allows access by any principal that has a shared
write lock on the same resource.

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o Any indirectly locked resource moved out of a locked source
collection into 2005

Note, however, that as new methods are created it will be necessary
to specify how they interact with a depth-infinity locked target collection remains
indirectly locked but is now within write lock.

7.3 Write Locks and Lock Tokens

A successful request for an exclusive or shared write lock MUST
result in the scope generation of a unique lock token associated with the
requesting principal. Thus if five principals have a shared write
lock on the
target collection (the target collection's lock token same resource there will
thereafter be required to make further changes).

If a depth-infinity write LOCK request is issued to a collection
containing member URLs identifying resources that are currently
locked in five lock tokens, one for
each principal.

7.4 Write Locks and Properties

While those without a manner which conflicts with the write lock, the request
MUST fail with lock may not alter a 423 (Locked) status code, and the response SHOULD
contain the 'missing-lock-token' precondition.

If property on a lock owner causes
resource it is still possible for the URL values of a resource live properties to be added as an
internal member URL of a depth-infinity locked collection then the
new resource MUST be automatically added
change, even while locked, due to the lock. This is the
only mechanism that allows a resource requirements of their schemas.
Only dead properties and live properties defined to be added respect locks are
guaranteed not to a change while write lock.
Thus, for example, if locked.

7.5 Avoiding Lost Updates

Although the collection /a/b/ is write locked and the
resource /c is moved to /a/b/c then resource /a/b/c locks provide some help in preventing lost
updates, they cannot guarantee that updates will never be added to lost.
Consider the write lock.

7.6 Write Locks following scenario:

Two clients A and B are interested in editing the If Request Header

If a user agent resource
'index.html'. Client A is an HTTP client rather than a WebDAV
client, and so does not required know how to have knowledge about a perform locking.

Client A doesn't lock when
requesting an operation on a locked resource, the following scenario
might occur. Program A, run by User A, takes out document, but does a write lock on GET and begins
editing.

Client B does LOCK, performs a
resource. Program B, also run by User A, has no knowledge of the
lock taken out by Program A, yet GET and begins editing.

Client B finishes editing, performs a PUT to PUT, then an UNLOCK.

Client A performs a PUT, overwriting and losing all of B's changes.

There are several reasons why the locked
resource. In WebDAV protocol itself cannot
prevent this scenario, the PUT succeeds situation. First, it cannot force all clients to use
locking because locks are
associated it must be compatible with a principal, HTTP clients that do not a program, and thus program B,
because
comprehend locking. Second, it is acting with principal Aȡs credential, is allowed cannot require servers to
perform the PUT. However, had program B known about support
locking because of the lock, variety of repository implementations, some of
which rely on reservations and merging rather than on locking.
Finally, being stateless, it
would not have overwritten the resource, preferring instead to
present cannot enforce a dialog box describing the conflict to sequence of operations
like LOCK / GET / PUT / UNLOCK.

WebDAV servers that support locking can reduce the user. Due to
this scenario, a mechanism is needed to prevent different programs
from likelihood that

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clients will accidentally ignoring locks taken out overwrite each other's changes by other programs with the
same authorization.

In order requiring
clients to prevent these collisions a lock token MUST be submitted
by an authorized principal for all locked resources that before modifying them. Such servers would
effectively prevent HTTP 1.0 and HTTP 1.1 clients from modifying
resources.

WebDAV clients can be good citizens by using a method may
change or the method MUST fail. A lock token is submitted when it
appears in an If header. For example, if / retrieve /
write /unlock sequence of operations (at least by default) whenever
they interact with a resource is to be moved
and both the source and destination are locked then two lock tokens
must WebDAV server that supports locking.

HTTP 1.1 clients can be submitted in the if header, one for the source and the good citizens, avoiding overwriting other
for the destination.

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Example -
clients' changes, by using entity tags in If-Match headers with any
requests that would modify resources.

Information managers may attempt to prevent overwrites by
implementing client-side procedures requiring locking before
modifying WebDAV resources.

7.6 Write Lock

>>Request

COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html
If: <http://www.ics.uci.edu/users/f/fielding/index.html>
(<opaquelocktoken:f81d4fae-7dec-11d0-a765-00a0c91e6bf6>)

>>Response

HTTP/1.1 204 No Content

In this example, even though both the source Locks and destination are
locked, only one Unmapped URLs

It is possible to lock token must be submitted, an unmapped URL in order to lock the name for
use. This is a simple way to avoid the lock lost-update problem on the
destination. This
creation of a new resource (another way is because to use If-None-Match
header specified in HTTP 1.1). It has the source side benefit of locking
the new resource immediately for use of the creator.

The lost-update problem is not modified by an issue for collections because MKCOL
can only be used to create a COPY, and hence unaffected by the write lock. collection, not to overwrite an existing
collection. In this example,
user agent authentication has previously occurred via order to immediately lock a mechanism
outside the scope of the HTTP protocol, in collection upon creation,
clients may attempt to pipeline the underlying transport
layer.

7.7 Write Locks MKCOL and COPY/MOVE LOCK requests together.

A COPY method invocation MUST NOT duplicate any write locks active on
the source. However, as previously noted, if the COPY copies lock request to an unmapped URL SHOULD result in the
resource into a collection that is creation of an
locked with "Depth: infinity",
then the resource will be added to the lock. with empty content. A successful MOVE subsequent PUT request on a write locked resource MUST NOT move
the write lock with
the resource. However, the resource is subject
to being added to an existing correct lock at the destination (see Section
7.5). For example, if the MOVE makes token SHOULD normally succeed, and this new request
provides the resource a child of content, content-type, content-language and other
information as appropriate.

In this situation, a
collection that is locked with "Depth: infinity", then the resource
will be added to WebDAV server that collection's lock. Additionally, if was implemented from RFC2518
MAY create "lock-null" resources which are special and unusual
resources. Historically, a resource
locked lock-null resource:

o Responds with "Depth: infinity" is moved a 404 or 405 to any DAV method except for PUT,
MKCOL, OPTIONS, PROPFIND, LOCK, UNLOCK.

o Appears as a destination that is
within the scope member of the same its parent collection.

o Disappears (URI becomes unmapped) if its lock (e.g., within the namespace tree
covered by the lock), the moved resource will again be a added goes away before it
is converted to the
lock. In both these examples, as specified in Section 7.6, an If
header must be submitted containing a lock token for both the source
and destination.

7.8 Refreshing Write Locks

A client MUST NOT submit the same write lock request twice. Note regular resource. (This must also happen if it
is renamed or moved, or if any parent collection is renamed or

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that a client is always aware it is resubmitting the same lock
request 2005

moved, because it must include the lock token in the If header in
order locks are tied to make the request for URLs).

o May be turned into a regular resource that is already locked.

However, a client may submit a LOCK method with an If header but
without when a body. This form of LOCK MUST only be used PUT request to "refresh" a
lock. Meaning, at minimum, that any timers associated with the lock
MUST
URL is successful. Ceases to be re-set.

A server may return a Timeout header with lock-null resource.

o May be turned into a lock refresh that is
different than the Timeout header returned collection when a MKCOL request to the lock was
originally requested. Additionally clients may submit Timeout
headers of arbitrary value with their lock refresh requests.
Servers, as always, may ignore Timeout headers submitted by the
client. Note that timeout URL is measured in seconds remaining until
expiration.

If an error is received in response
successful. Ceases to be a refresh LOCK request the
client MUST NOT assume that the lock was refreshed.

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8. HTTP Methods lock-null resource.

o Has defined values for Distributed Authoring

8.1 General request and response handling

8.1.1 Use of XML

Some of the following new HTTP methods use XML as a request lockdiscovery and
response format. All DAV compliant clients supportedlock properties.

However, interoperability and resources MUST use
XML parsers that are compliant compliance problems have been found
with XML [11] lock-null resources. Therefore, they are deprecated. WebDAV
servers SHOULD create regular locked empty resources, which are and XML Namespaces [10].
All XML used
behave in either requests or responses MUST be, at minimum,
well formed every way as normal resources. A locked empty resource:

o Can be read, deleted, moved, copied, and use namespaces correctly. If a server receives non-
wellformed XML in all ways behave as a request it MUST reject the entire request with a
400 (Bad Request). If
regular resource, not a client receives ill-formed XML in lock-null resource.

o Appears as a response
then it MUST NOT assume anything about the outcome member of the executed
method and its parent collection.

o SHOULD treat the server as malfunctioning.

8.1.2 Required Bodies in Requests

Some of these new methods do not define bodies. Servers MUST examine
all requests for a body, even NOT disappear when a body was not expected. In cases
where a request body is present but would be ignored by a server, the
server MUST reject the request its lock goes away (clients must
therefore be responsible for cleaning up their own mess, as with 415 (Unsupported Media Type).
This informs the client (which may
any other operation)

o SHOULD default to having no content type.

o MAY NOT have values for properties like getcontentlanguage which
haven't been attempting to use an
extension) that specified yet by the body could not client.

o May have content added with a PUT request. MUST be processed able to change
content type.

o MUST NOT be turned into a collection. A MKCOL request must fail
as they intended.

8.1.3 Use it would to any existing resource.

o MUST have defined values for lockdiscovery and supportedlock
properties.

o The response MUST indicate that a resource was created, by use of Location header in responses

When
the Location header is used "201 Created" response code (a LOCK request to an existing
resource instead will result in 200 OK). The body must still
include the lockdiscovery property, as with a response, it LOCK request to an
existing resource.

The client is used by the
server expected to indicate update the preferred address for locked empty resource shortly
after locking it, using PUT and possibly PROPPATCH. When the target client
uses PUT to overwrite a locked empty resource of the request. Whenever client MUST supply
a Content-Type if any is known. If the server has client supplies a preferred address, it should
use Content-

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Type value the server MUST set that address consistently. This means value (this requirement actually
applies to any resource that when is overwritten but is particularly
necessary for locked empty resources which are initially created with
no Content-Type.

7.7 Write Locks and Collections

A write lock on a Location header, all collection, whether created by a "Depth: 0" or
"Depth: infinity" lock request, prevents the addition or removal of
member URLs in of the response body (e.g. collection by non-lock owners.

A zero-depth lock on a Multi-Status) should be consistent (most importantly, should use
the same host and port).

8.1.4 Required Response Headers: Date

Note that HTTP 1.1 requires the Date header in all responses if
possible.

8.1.5 ETag

HTTP 1.1 recommends collection affects changes to the use direct
membership of the ETag header in responses that collection. When a principal issues a write
request to GET
and PUT requests. Correct use of ETags is even more important create a new resource in a
distributed authoring environment, because ETags are necessary along
with locks to avoid write locked collection, or
isses a DELETE, MOVE or other request that would remove an existing
internal member URL of a write locked collection or change the lost-update problem. A client might
binding name, this request MUST fail to
renew a lock, for example when if the principal does not
provide the correct lock times out and token for the client locked collection.

This means that if a collection is
accidentally offline locked (depth 0 or infinity), its
lock-token is required in the middle all these cases:

o DELETE a collection's direct internal member

o MOVE a member out of the collection

o MOVE a long upload. When member into the collection, unless it overwrites a pre-
existing member

o MOVE to rename it within a collection,

o COPY a member into a collection, unless it overwrites a pre-
existing member

o PUT or MKCOL request which would create a new member.

The collection's lock token is required in addition to the lock token
on the internal member itself, if it is locked separately.

In addition, a depth-infinity lock affects all write operations to
all descendents of the locked collection. With a depth-infinity
lock, the root of the lock is directly locked, and all its
descendants are indirectly locked.

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client fails to renew the lock, it's quite possible the 2005

o Any new resource can
still be relocked and the user can go on editing, as long added as no
changes were made in the meantime. ETags are required for the client
to be able to distinguish this case. Otherwise, a descendent of a depth-infinity locked
collection becomes indirectly locked.

o Any indirectly locked resource moved out of the client locked collection
into an unlocked collection is forced
to ask thereafter unlocked.

o Any indirectly locked resource moved out of a locked source
collection into a depth-infinity locked target collection remains
indirectly locked but is now within the user whether to overwrite scope of the resource lock on the server
without even being able
target collection (the target collection's lock token will
thereafter be required to tell the user whether it has changed.
Timestamps do not solve this problem nearly as well as ETags.

WebDAV servers SHOULD support strong ETags for all make further changes).

If a depth-infinity write LOCK request is issued to a collection
containing member URLs identifying resources that may
be PUT. If ETags are supported for currently
locked in a resource, manner which conflicts with the server MUST
return write lock, the ETag header in all PUT request
MUST fail with a 423 (Locked) status code, and GET responses to that resource,
as well as provide the same value for the 'getetag' property.

Because clients may be forced to prompt users or throw away changed
content if response SHOULD
contain the ETag changes, 'missing-lock-token' precondition.

If a WebDAV server MUST not change lock owner causes the ETag
(or getlastmodified value) for URL of a resource that has to be added as an unchanged body.
The ETag represents the state of the body or contents
internal member URL of a depth-infinity locked collection then the
resource. There is no similar way
new resource MUST be automatically added to tell if properties have
changed.

8.1.6 Including error response bodies

HTTP and WebDAV did not use the bodies of most error responses for
machine-parsable information until DeltaV introduced a mechanism to
include more specific information in lock. This is the body of an error response
(section 1.6 of RFC3253 [18]). The
only mechanism is appropriate to use
with any error response that may take allows a body but does not already
have resource to be added to a body defined. The mechanism write lock.
Thus, for example, if the collection /a/b/ is particularly appropriate when
a status code can mean many things (for example, 400 Bad write locked and the
resource /c is moved to /a/b/c then resource /a/b/c will be added to
the write lock.

7.8 Write Locks and the If Request can
mean required headers are missing, headers are incorrectly formatted,
or much more).

This mechanism does Header

If a user agent is not take required to have knowledge about a lock when
requesting an operation on a locked resource, the place of using following scenario
might occur. Program A, run by User A, takes out a correct numeric
error code as defined here or in HTTP, because write lock on a
resource. Program B, also run by User A, has no knowledge of the client MUST always
be able
lock taken out by Program A, yet performs a PUT to take the locked
resource. In this scenario, the PUT succeeds because locks are
associated with a reasonable course of action based only on principal, not a program, and thus program B,
because it is acting with principal Ais credential, is allowed to
perform the
numeric error. PUT. However, had program B known about the lock, it does remove
would not have overwritten the need resource, preferring instead to define new
numeric error codes, avoiding
present a dialog box describing the confusion of who is allowed conflict to the user. Due to
define such new codes. The codes used in
this mechanism are XML
elements in a namespace, so naturally any group defining scenario, a new error
code can use their own namespace. As always, the "DAV:" namespace mechanism is
reserved for use by IETF-chartered WebDAV working groups.

A server supporting "bis" SHOULD include a specific XML error code in needed to prevent different programs
from accidentally ignoring locks taken out by other programs with the
same authorization.

In order to prevent these collisions a "DAV:error" response body element, when lock token MUST be submitted
by an authorized principal for all locked resources that a specific XML error code
is defined in this document. The ȼDAV:errorȫ element method may contain
multiple elements describing specific errors. For error conditions
not specified in this document,
change or the server MAY simply choose method MUST fail. A lock token is submitted when it
appears in an
appropriate numeric status If header. For example, if a resource is to be moved
and leave both the response body blank. source and destination are locked then two lock tokens

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must be submitted in the if header, one for the source and the other
for the destination.

Example - Write Lock

>>Request

COPY /~fielding/index.html HTTP/1.1 403 Forbidden
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:error xmlns:D="DAV:">
<D:forbid-external-entities/>
</D:error>
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html
If: <http://www.ics.uci.edu/users/f/fielding/index.html>
(<opaquelocktoken:f81d4fae-7dec-11d0-a765-00a0c91e6bf6>)

>>Response

HTTP/1.1 204 No Content

In this specification, example, even though both the numeric source and the XML error code destination are
defined for some failure situations, in which case the XML error code
locked, only one lock token must have the "DAV:" namespace, appear in the "error" root element,
and be returned in a body with submitted, for the numeric error code specified.

8.2 PROPFIND

The PROPFIND method retrieves properties defined lock on the resource
identified by the Request-URI, if
destination. This is because the source resource does is not have any
internal members, or on the resource identified modified by
a COPY, and hence unaffected by the Request-URI write lock. In this example,
user agent authentication has previously occurred via a mechanism
outside the scope of the HTTP protocol, in the underlying transport
layer.

7.9 Write Locks and potentially its member resources, COPY/MOVE

A COPY method invocation MUST NOT duplicate any write locks active on
the source. However, as previously noted, if the COPY copies the
resource is into a collection that has internal member URLs. All DAV compliant resources MUST
support is locked with "Depth: infinity",
then the PROPFIND method and resource will be added to the propfind XML element (Section
13.25) along with all XML elements defined for use with that element. lock.

A client may submit successful MOVE request on a Depth header write locked resource MUST NOT move
the write lock with the resource. However, the resource is subject
to being added to an existing lock at the destination (see
Section 7.7). For example, if the MOVE makes the resource a value child of "0", "1", or
"infinity" with a PROPFIND on
a collection resource. Servers MUST
support the "0", "1" and "infinity" behaviors on WebDAV-compliant
resources. By default, that is locked with "Depth: infinity", then the PROPFIND method without a Depth header
MUST act as resource
will be added to that collection's lock. Additionally, if a resource
locked with "Depth: infinity" header was included.

A client may submit is moved to a propfind XML element in destination that is
within the body scope of the request
method describing what information is being requested. It is
possible to request:

o Request particular property values, by naming the properties
desired same lock (e.g., within the 'prop' element (the ordering of properties in
here MAY be ignored by server)
o Request all dead property values, by using 'dead-props' element.
This can be combined with retrieving specific live properties
named as above. Servers advertising support for RFC2518bis MUST
support this feature.
o Request property values for those properties defined in this
specification plus dead properties, namespace tree
covered by using 'allprop' element
o Request a list of names of all the properties defined on the
resource, by using lock), the 'propname' element.

A client may choose not to submit a request body. An empty PROPFIND
request body MUST moved resource will again be treated a added to the
lock. In both these examples, as if it were specified in Section 7.8, an 'allprop' request. If
header must be submitted containing a lock token for both the source
and destination.

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7.10 Refreshing Write Locks

A client MUST NOT submit the same write lock request twice. Note
that 'allprop' does not return values for all live properties.
WebDAV servers increasingly have expensively-calculated or lengthy
properties (see RFC3253 [18] and RFC3744 [19]) and do not return all
properties already. Instead, WebDAV clients can use propname
requests to discover what live properties exist, and a client is always aware it is resubmitting the same lock
request named
properties when retrieving values. A WebDAV server MAY omit certain
live properties from other specifications when responding because it must include the lock token in the If header in
order to an
allprop make the request from an older client, and MAY return only custom
(dead) properties and those defined in this specification.

All servers MUST support returning for a response of content type text/
xml or application/xml resource that contains is already locked.

However, a multistatus XML element that
describes the results client may submit a LOCK method with an If header but
without a body. This form of the attempts LOCK MUST only be used to retrieve "refresh" a
lock. Meaning, at minimum, that any timers associated with the various
properties. The multistatus contains one response element for each
resource in lock
MUST be re-set.

A server may return a Timeout header with a lock refresh that is
different than the scope of Timeout header returned when the request (in no required order) or lock was
originally requested. Additionally clients may be
empty if no resources match submit Timeout
headers of arbitrary value with their lock refresh requests.
Servers, as always, may ignore Timeout headers submitted by the request.

If there
client. Note that timeout is measured in seconds remaining until
expiration.

If an error retrieving a property then is received in response to a proper error result refresh LOCK request the
client MUST be included in NOT assume that the response. A lock was refreshed.

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8. HTTP Methods for Distributed Authoring

8.1 General request to retrieve the value and response handling

8.1.1 Use of XML

Some of the following new HTTP methods use XML as a property which does not exist is an error request and MUST be noted, if the
response uses a multistatus format. All DAV compliant clients and resources MUST use
XML element, parsers that are compliant with a response XML element
which contains [11] and XML Namespaces [10].
All XML used in either requests or responses MUST be, at minimum,
well formed and use namespaces correctly. If a 404 (Not Found) status value.

Consequently, the multistatus server receives non-
wellformed XML element for in a collection resource
with member URLs request it MUST include reject the entire request with a response
400 (Bad Request). If a client receives ill-formed XML element for each member
URL of the collection, to whatever depth was requested. Each in a response XML element
then it MUST contain an href XML element that gives NOT assume anything about the
URL outcome of the resource on which the properties in executed
method and SHOULD treat the prop XML element
are defined. URLs for collections appearing server as malfunctioning.

8.1.2 Required Bodies in the results Requests

Some of these new methods do not define bodies. Servers MUST end
in a slash character. Results examine
all requests for a PROPFIND on a collection
resource with internal member URLs are returned as body, even when a flat list whose
order of entries is body was not significant.

A server enumerating the members of expected. In cases
where a collection using absolute URLs
in request body is present but would be ignored by a PROPFIND response server, the
server MUST reject the request with 415 (Unsupported Media Type).
This informs the client (which may have been attempting to use a common prefix in those URLs, and an
extension) that prefix MUST the body could not be processed as they intended.

8.1.3 Use of Location header in responses

When the absolute URL Location header is used in a response, it is used by the response
server to refer to
the parent collection.

Unless otherwise notified, clients may expect that indicate the URL preferred address for the
parent collection target resource of
the request. Whenever the server has a preferred address, it should
use that address consistently. This means that when a response
contains a Location header, all the URLs in the PROPFIND response will body (e.g. a
Multi-Status) should be consistent (most importantly, should use the
same URL host and port).

8.1.4 Required Response Headers: Date

Note that
was used to refer to HTTP 1.1 requires the parent collection Date header in all responses if
possible.

8.1.5 ETag

HTTP 1.1 recommends the PROPFIND request.
Servers MAY use an alternate URL for of the parent collection ETag header in a
PROPFIND response, but responses to GET
and PUT requests. Correct use of ETags is even more important in this case the server MUST include a
Content-Location header whose value is the fully-qualified URL used
by the server
distributed authoring environment, because ETags are necessary along
with locks to refer avoid the lost-update problem. A client might fail to
renew a lock, for example when the parent collection lock times out and the client is
accidentally offline or in this response.

Clients expect the fully-qualified URLs of members middle of a collection to
have long upload. When a common prefix which is the fully-qualified URL of the parent

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collection itself.

URLs in a PROPFIND response body MAY 2005

client fails to renew the lock, it's quite possible the resource can
still be represented relocked and the user can go on editing, as fully-
qualified URLs, long as no
changes were made in which case they must all contain the full parent
collection URL (scheme, host, port, and absolute path).
Alternatively, these URLs MAY meantime. ETags are required for the client
to be absolute paths (not containing
scheme, host or port), but in able to distinguish this case they must all still contain case. Otherwise, the full parent collection path.

If a server allows resource names client is forced
to include characters that arenȡt
legal in HTTP URL paths, these characters must be URI-escaped ask the user whether to overwrite the resource on the
wire. For example, it is illegal server
without even being able to use a space character or double-
quote in a URI [6]. URIs appearing in PROPFIND or PROPPATCH XML
bodies (or other XML marshalling defined in tell the user whether it has changed.
Timestamps do not solve this specification) are
still subject to problem nearly as well as ETags.

WebDAV servers SHOULD support strong ETags for all URI rules, including forbidden characters.

Properties resources that may
be subject to access control. In PUT. If ETags are supported for a resource, the case of allprop server MUST
return the ETag header in all PUT and propname, GET responses to that resource,
as well as provide the same value for the 'getetag' property.

Because clients may be forced to prompt users or throw away changed
content if the ETag changes, a principal does WebDAV server MUST not have change the right to know whether ETag
(or getlastmodified value) for a particular property exists then resource that has an unchanged body.
The ETag represents the property MAY be silently
excluded from state of the response.

The results body or contents of this method SHOULD NOT be cached.

8.2.1 Example - Retrieving Named Properties

>>Request

PROPFIND /file HTTP/1.1
Host: www.example.com
Content-type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:propfind xmlns:D="DAV:">
<D:prop xmlns:R="http://www.example.com/boxschema/">
<R:bigbox/>
<R:author/>
<R:DingALing/>
<R:Random/>
</D:prop>
</D:propfind>

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

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<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:">
<D:response xmlns:R="http://www.example.com/boxschema/">
<D:href>http://www.example.com/file</D:href>
<D:propstat>
<D:prop>
<R:bigbox>
<R:BoxType>Box type A</R:BoxType>
</R:bigbox>
<R:author>
<R:Name>J.J. Johnson</R:Name>
</R:author>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
<D:propstat>
<D:prop><R:DingALing/><R:Random/></D:prop>
<D:status>HTTP/1.1 403 Forbidden</D:status>
<D:responsedescription> The user does not have access to the
DingALing property.
</D:responsedescription>
</D:propstat>
</D:response>
<D:responsedescription>
resource. There has been an access violation error.
</D:responsedescription>
</D:multistatus>

In this example, PROPFIND is executed on a non-collection resource
http://www.example.com/file. The propfind XML element specifies the
name of four properties whose values are being requested. In this
case only two no similar way to tell if properties were returned, since the principal issuing
the request have
changed.

8.1.6 Including error response bodies

HTTP and WebDAV did not have sufficient access rights to see use the third
and fourth properties.

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8.2.2 Example - Retrieving Named and Dead Properties

>>Request

PROPFIND /mycol/ HTTP/1.1
Host: www.example.com
Depth: 1
Content-type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:propfind xmlns:D="DAV:">
<D:prop>
<D:creationdate/>
<D:getlastmodified/>
</D:prop>
<D:dead-props/>
</D:propfind>

In this example, PROPFIND is executed on bodies of most error responses for
machine-parsable information until DeltaV introduced a collection resource http:/
/www.example.com/mycol/. The client requests mechanism to
include more specific information in the values body of two
specific live properties plus all dead properties (names and values). an error response
(section 1.6 of RFC3253 [14]). The mechanism is appropriate to use
with any error response that may take a body but does not already
have a body defined. The mechanism is particularly appropriate when
a status code can mean many things (for example, 400 Bad Request can
mean required headers are missing, headers are incorrectly formatted,
or much more).

This mechanism does not shown.

8.2.3 Example - Using propname take the place of using a correct numeric
error code as defined here or in HTTP, because the client MUST always
be able to Retrieve all Property Names

>>Request
PROPFIND /container/ take a reasonable course of action based only on the
numeric error. However, it does remove the need to define new
numeric error codes, avoiding the confusion of who is allowed to
define such new codes. The codes used in this mechanism are XML
elements in a namespace, so naturally any group defining a new error
code can use their own namespace. As always, the "DAV:" namespace is
reserved for use by IETF-chartered WebDAV working groups.

A server supporting "bis" SHOULD include a specific XML error code in
a "DAV:error" response body element, when a specific XML error code
is defined in this document. The DAV:error element may contain
multiple elements describing specific errors. For error conditions
not specified in this document, the server MAY simply choose an
appropriate numeric status and leave the response body blank.

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HTTP/1.1
Host: www.example.com 403 Forbidden
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<propfind xmlns="DAV:">
<propname/>
</propfind>

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<multistatus xmlns="DAV:">
<response>
<href>http://www.example.com/container/</href>
<propstat>

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<prop xmlns:R="http://www.example.com/boxschema/">
<R:bigbox/>
<R:author/>
<creationdate/>
<displayname/>
<resourcetype/>
<supportedlock/>
</prop>
<status>HTTP/1.1 200 OK</status>
</propstat>
</response>
<response>
<href>http://www.example.com/container/front.html</href>
<propstat>
<prop xmlns:R="http://www.example.com/boxschema/">
<R:bigbox/>
<creationdate/>
<displayname/>
<getcontentlength/>
<getcontenttype/>
<getetag/>
<getlastmodified/>
<resourcetype/>
<supportedlock/>
</prop>
<status>HTTP/1.1 200 OK</status>
</propstat>
</response>
</multistatus>
<D:error xmlns:D="DAV:">
<D:forbid-external-entities/>
</D:error>

In this example, PROPFIND is invoked on specification, both the collection resource
http://www.example.com/container/, with a propfind XML element
containing numeric and the propname XML element, meaning the name of all
properties should be returned. Since no Depth header is present, it
assumes its default value of "infinity", meaning error code are
defined for some failure situations, in which case the name of XML error code
must have the
properties on "DAV:" namespace, appear in the collection "error" root element,
and all its descendents should be
returned.

Consistent returned in a body with the previous example, resource http://
www.example.com/container/ has six numeric error code specified.

8.2 PROPFIND

The PROPFIND method retrieves properties defined on it: bigbox
and author in the "http://www.example.com/boxschema/" namespace, and
creationdate, displayname, resourcetype, and supportedlock in resource
identified by the Request-URI, if the
"DAV:" namespace.

The resource http://www.example.com/container/index.html, a does not have any
internal members, or on the resource identified by the Request-URI
and potentially its member of resources, if the "container" collection, resource is a collection
that has nine properties defined on it, bigbox
in internal member URLs. All DAV compliant resources MUST
support the "http://www.example.com/boxschema/" namespace and,
creationdate, displayname, getcontentlength, getcontenttype, getetag,

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getlastmodified, resourcetype, PROPFIND method and supportedlock in the "DAV:"
namespace.

This example also demonstrates the use of propfind XML namespace scoping and
the default namespace. Since the "xmlns" attribute does not contain
a prefix, the namespace applies by default to all enclosed elements.
Hence, element
(Section 13.25) along with all XML elements which do not explicitly state the namespace to
which they belong are members of the "DAV:" namespace schema.

8.2.4 PROPFIND Request Errors

PROPFIND requests may also fail entirely, before the server even gets
a chance to evaluate individual properties. 404 (Not Found) and 401
(Unauthorized) are possible as defined for use with every request. These are some
other notable errors.

403 Forbidden - that
element.

A server MAY reject all PROPFIND requests on
collections with depth client may submit a Depth header with a value of "Infinity", in which case it SHOULD
use this error "0", "1", or
"infinity" with the element 'propfind-infinite-depth-forbidden'
inside the body.

8.3 PROPPATCH

The PROPPATCH method processes instructions specified in the request
body to set and/or remove properties defined a PROPFIND on the resource
identified by the Request-URI.

All DAV compliant resources a collection resource. Servers MUST
support the PROPPATCH method "0", "1" and
MUST process instructions that are specified using "infinity" behaviors on WebDAV-compliant
resources. By default, the
propertyupdate, set, and remove PROPFIND method without a Depth header
MUST act as if a "Depth: infinity" header was included.

A client may submit a propfind XML elements. Execution of the
directives element in this method is, of course, subject to access control
constraints. DAV compliant resources SHOULD support the setting of
arbitrary dead properties.

The request message body of a PROPPATCH method MUST contain the
propertyupdate XML element. Instruction processing MUST occur in
document order (an exception to request
method describing what information is being requested. It is
possible to:

o Request particular property values, by naming the normal rule that properties
desired within the 'prop' element (the ordering is
irrelevant). Instructions MUST either all of properties in
here MAY be executed or none
executed. Thus if any error occurs during processing ignored by server)

o Request all executed
instructions MUST be undone and a proper error result returned.
Instruction processing details dead property values, by using 'dead-props' element.
This can be found in the definition of the
set and remove instructions in sections 13.23 and section 13.24.

8.3.1 Status Codes for use combined with 207 (Multi-Status)

The following are examples of response codes one would expect to be
used in a 207 (Multi-Status) response retrieving specific live properties
named as above. Servers advertising support for RFC2518bis MUST
support this method. Note,
however, that unless explicitly prohibited any 2/3/4/5xx series feature.

o Request property values for those properties defined in this
specification plus dead properties, by using 'allprop' element

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response code may be used in a 207 (Multi-Status) response.

200 (OK) - The command succeeded. As there can be 2005

o Request a mixture list of sets
and removes in a body, a 201 (Created) seems inappropriate.

403 (Forbidden) - The client, for reasons the server chooses not to
specify, cannot alter one names of all the properties.

403 (Forbidden): The properties defined on the
resource, by using the 'propname' element.

A client has attempted may choose not to set submit a read- only
property, such request body. An empty PROPFIND
request body MUST be treated as getetag. If returning this error, the server
SHOULD if it were an 'allprop' request.

Note that 'allprop' does not return values for all live properties.
WebDAV servers increasingly have expensively-calculated or lengthy
properties (see RFC3253 [14] and RFC3744 [15]) and do not return all
properties already. Instead, WebDAV clients can use 'read-only-property' inside the propname
requests to discover what live properties exist, and request named
properties when retrieving values. A WebDAV server MAY omit certain
live properties from other specifications when responding to an
allprop request from an older client, and MAY return only custom
(dead) properties and those defined in this specification.

All servers MUST support returning a response body.

409 (Conflict) - The client has provided of content type text/
xml or application/xml that contains a value whose semantics are
not appropriate for multistatus XML element that
describes the property.

423 (Locked) - results of the attempts to retrieve the various
properties. The specified multistatus contains one response element for each
resource is locked and in the client either
is not a lock owner scope of the request (in no required order) or may be
empty if no resources match the lock type requires request.

If there is an error retrieving a lock token to property then a proper error result
MUST be
submitted and the client did not submit it. This response SHOULD
contain included in the 'missing-lock-token' precondition element.

507 (Insufficient Storage) - The server did not have sufficient space response. A request to record the property.

8.3.2 Example - PROPPATCH

>>Request

PROPPATCH /bar.html HTTP/1.1
Host: www.example.com
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:propertyupdate xmlns:D="DAV:"
xmlns:Z="http://www.w3.com/standards/z39.50/">
<D:set>
<D:prop>
<Z:authors>
<Z:Author>Jim Whitehead</Z:Author>
<Z:Author>Roy Fielding</Z:Author>
</Z:authors>
</D:prop>
</D:set>
<D:remove>
<D:prop><Z:Copyright-Owner/></D:prop>
</D:remove>
</D:propertyupdate>

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>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:Z="http://www.w3.com/standards/z39.50">
<D:response>
<D:href>http://www.example.com/bar.html</D:href>
<D:propstat>
<D:prop><Z:Authors/></D:prop>
<D:status>HTTP/1.1 424 Failed Dependency</D:status>
</D:propstat>
<D:propstat>
<D:prop><Z:Copyright-Owner/></D:prop>
<D:status>HTTP/1.1 409 Conflict</D:status>
</D:propstat>
<D:responsedescription> Copyright Owner can not be deleted or
altered.</D:responsedescription>
</D:response>
</D:multistatus>

In this example, the client requests the server to set retrieve the value of
the "Authors" property in the "http://www.w3.com/standards/z39.50/"
namespace, and to remove the property "Copyright-Owner" in the
"http://www.w3.com/standards/z39.50/" namespace. Since the
Copyright-Owner
a property could which does not exist is an error and MUST be removed, no property
modifications occur. The 424 (Failed Dependency) status code for the
Authors property indicates this action would have succeeded noted, if it
were not for the conflict
response uses a multistatus XML element, with removing the Copyright-Owner property.

8.4 MKCOL Method

The MKCOL method is used to create a new collection. All WebDAV
compliant resources MUST support response XML element
which contains a 404 (Not Found) status value.

Consequently, the MKCOL method.

MKCOL creates multistatus XML element for a new collection resource at
with member URLs MUST include a response XML element for each member
URL of the location specified by collection, to whatever depth was requested. Each
response XML element MUST contain an href XML element that gives the Request-URI. If
URL of the resource identified by on which the Request-URI is
non-null then properties in the MKCOL MUST fail. During MKCOL processing, a server
MUST make prop XML element
are defined. URLs for collections appearing in the Request-URI results MUST end
in a slash character. Results for a PROPFIND on a collection
resource with internal member URLs are returned as a flat list whose
order of its parent collection, unless
the Request-URI entries is "/". If no such ancestor exists, the method MUST
fail. When not significant.

A server enumerating the MKCOL operation creates members of a new collection resource,
all ancestors MUST already exist, or the method MUST fail with using absolute URLs
in a 409
(Conflict) status code. For example, if PROPFIND response MUST use a request common prefix in those URLs, and
that prefix MUST be the absolute URL used in the response to create refer to
the parent collection.

Unless otherwise notified, clients may expect that the URL for the
parent collection /a/b/c/d/ is made, and /a/b/c/ does not exist, in the request
must fail. PROPFIND response will be the same URL that
was used to refer to the parent collection in the PROPFIND request.
Servers MAY use an alternate URL for the parent collection in a

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When MKCOL is invoked without a request body, 2005

PROPFIND response, but in this case the newly created
collection SHOULD have no members.

A MKCOL request message may contain a message body. The behavior of server MUST include a MKCOL request when the body is present
Content-Location header whose value is limited to creating
collections, members of a collection, bodies of members and
properties on the collections or members. If fully-qualified URL used
by the server receives a
MKCOL request entity type it does not support or understand it MUST
respond with a 415 (Unsupported Media Type) status code. If the
server decides to reject the request based on the presence of an
entity or the type of an entity, it should use refer to the 415 (Unsupported
Media Type) status code. The exact behavior of MKCOL for various
request media types is undefined parent collection in this document, and will be
specified response.

URLs in separate documents.

8.4.1 MKCOL Status Codes

Responses from a MKCOL request MUST NOT PROPFIND response body MAY be cached represented as MKCOL has non-
idempotent semantics.

201 (Created) - The collection was created.

403 (Forbidden) - This indicates at least one of two conditions: 1)
the server does not allow the creation of collections at the given
location fully-
qualified URLs, in its namespace, or 2) which case they must all contain the full parent
collection of the
Request-URI exists but cannot accept members.

405 (Method Not Allowed) - MKCOL can only be executed on an unmapped
URL.

409 (Conflict) - A collection cannot URL (scheme, host, port, and absolute path).
Alternatively, these URLs MAY be made at the Request-URI until
one absolute paths (not containing
scheme, host or more intermediate collections have been created. The server
MUST NOT create those intermediate collections automatically.

415 (Unsupported Media Type) - The server does not support the
request type of port), but in this case they must all still contain
the body.

507 (Insufficient Storage) - The full parent collection path.

If a server allows resource does not have sufficient
space names to record the state of the resource after the execution include characters that arenit
legal in HTTP URL paths, these characters must be URI-escaped on the
wire. For example, it is illegal to use a space character or double-
quote in a URI [5]. URIs appearing in PROPFIND or PROPPATCH XML
bodies (or other XML marshalling defined in this specification) are
still subject to all URI rules, including forbidden characters.

Properties may be subject to access control. In the case of allprop
and propname, if a principal does not have the right to know whether
a particular property exists then the property MAY be silently
excluded from the response.

The results of this
method.

8.4.2 method SHOULD NOT be cached.

8.2.1 Example - MKCOL

This example creates a collection called /webdisc/xfiles/ on the
server www.example.com. Retrieving Named Properties

>>Request

PROPFIND /file HTTP/1.1
Host: www.example.com
Content-type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:propfind xmlns:D="DAV:">
<D:prop xmlns:R="http://www.example.com/boxschema/">
<R:bigbox/>
<R:author/>
<R:DingALing/>
<R:Random/>
</D:prop>
</D:propfind>

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"

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>>Request

MKCOL /webdisc/xfiles/ HTTP/1.1
Host: www.example.com

>>Response

HTTP/1.1 201 Created

8.5 GET, HEAD for Collections 2005

Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:">
<D:response xmlns:R="http://www.example.com/boxschema/">
<D:href>http://www.example.com/file</D:href>
<D:propstat>
<D:prop>
<R:bigbox>
<R:BoxType>Box type A</R:BoxType>
</R:bigbox>
<R:author>
<R:Name>J.J. Johnson</R:Name>
</R:author>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
<D:propstat>
<D:prop><R:DingALing/><R:Random/></D:prop>
<D:status>HTTP/1.1 403 Forbidden</D:status>
<D:responsedescription> The semantics of GET are unchanged when applied user does not have access to a collection,
since GET is defined as, "retrieve whatever information (in the form
of
DingALing property.
</D:responsedescription>
</D:propstat>
</D:response>
<D:responsedescription> There has been an entity) access violation error.
</D:responsedescription>
</D:multistatus>

In this example, PROPFIND is identified by the Request-URI" [RFC2616]. GET when
applied to a collection may return the contents of an "index.html"
resource, a human-readable view of the contents of the collection, or
something else altogether. Hence it is possible that the result of a
GET executed on a collection will bear no correlation to the membership of the
collection.

Similarly, since the definition of HEAD is a GET without a response
message body, the semantics of HEAD are unmodified when applied to
collection resources.

8.6 POST for Collections

Since by definition the actual function performed by POST is
determined by the server and often depends on the particular
resource, the behavior of POST when applied to collections cannot be
meaningfully modified because it is largely undefined. Thus non-collection resource
http://www.example.com/file. The propfind XML element specifies the
semantics
name of POST four properties whose values are unmodified when applied to a collection.

8.7 DELETE

8.7.1 DELETE for Non-Collection Resources

When a client issues a DELETE request to a Request-URI mapping to a
non-collection resource, if the operation is successful being requested. In this
case only two properties were returned, since the server
MUST remove that mapping. Thus, after a successful DELETE operation
(and in principal issuing
the absence of other actions) a subsequent GET/HEAD/PROPFIND request did not have sufficient access rights to see the target Request-URI MUST return 404 (Not Found).

8.7.2 DELETE for Collections

The DELETE method on a collection MUST act as if a "Depth: infinity"
header was used on it. A client MUST NOT submit a Depth header with third
and fourth properties.

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a DELETE 2005

8.2.2 Example - Retrieving Named and Dead Properties

>>Request

PROPFIND /mycol/ HTTP/1.1
Host: www.example.com
Depth: 1
Content-type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:propfind xmlns:D="DAV:">
<D:prop>
<D:creationdate/>
<D:getlastmodified/>
</D:prop>
<D:dead-props/>
</D:propfind>

In this example, PROPFIND is executed on a collection with any value but infinity.

DELETE instructs that the collection specified in resource
http://www.example.com/mycol/. The client requests the Request-URI and values of two
specific live properties plus all resources identified by its internal member URLs are dead properties (names and values).
The response is not shown.

8.2.3 Example - Using propname to be
deleted.

If any Retrieve all Property Names

>>Request
PROPFIND /container/ HTTP/1.1
Host: www.example.com
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<propfind xmlns="DAV:">
<propname/>
</propfind>

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<multistatus xmlns="DAV:">
<response>
<href>http://www.example.com/container/</href>
<propstat>

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In this example, PROPFIND is invoked on the collection resource identified by
http://www.example.com/container/, with a member URL cannot be deleted then propfind XML element
containing the propname XML element, meaning the name of all
properties should be returned. Since no Depth header is present, it
assumes its default value of "infinity", meaning the member's ancestors MUST NOT name of the
properties on the collection and all its descendents should be deleted, so as to maintain
namespace consistency.

Any headers included
returned.

Consistent with DELETE MUST be applied in processing every
resource to be deleted.

When the DELETE method previous example, resource
http://www.example.com/container/ has completed processing it MUST result six properties defined on it:
bigbox and author in a
consistent namespace.

If an error occurs deleting an internal resource (a resource other
than the resource identified "http://www.example.com/boxschema/"
namespace, and creationdate, displayname, resourcetype, and
supportedlock in the Request-URI) then the response
can be a 207 (Multi-Status). Multi-Status is used here to indicate
which internal resources could NOT be deleted, including an error
code which should help the client understand which resources caused
the failure. For example, the Multi-Status body could include a
response with status 423 (Locked) if an internal resource was locked. "DAV:" namespace.

The server MAY return a 4xx status response, rather than resource http://www.example.com/container/index.html, a Multi-
Status, if the entire DELETE request failed and it canȡt identify
the internal resources that caused the DELETE to fail.

424 (Failed Dependency) errors SHOULD NOT be in the 207 (Multi-
Status). They can be safely left out because the client will know
that the ancestors member of a resource could not be deleted when the client
receives an error for
the ancestor's progeny. Additionally 204 (No
Content) errors SHOULD NOT be returned "container" collection, has nine properties defined on it, bigbox
in the 207 (Multi- Status).
The reason for this prohibition is that 204 (No Content) is the
default success code. "http://www.example.com/boxschema/" namespace and,
creationdate, displayname, getcontentlength, getcontenttype, getetag,

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8.7.3 Example - DELETE

>>Request

DELETE /container/ HTTP/1.1
Host: www.example.com

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<d:multistatus xmlns:d="DAV:">
<d:response>
<d:href>http://www.example.com/container/resource3</d:href>
<d:status>HTTP/1.1 423 Locked</d:status>
</d:response>
</d:multistatus>

In this example the attempt to delete http://www.example.com/
container/resource3 failed because it is locked, 2005

getlastmodified, resourcetype, and no lock token
was submitted with the request. Consequently, supportedlock in the attempt to delete
http://www.example.com/container/ "DAV:"
namespace.

This example also failed. Thus demonstrates the client knows
that use of XML namespace scoping and
the attempt to delete http://www.example.com/container/ must
have also failed since default namespace. Since the parent can "xmlns" attribute does not be deleted unless its child
has also been deleted. Even though contain
a Depth header has prefix, the namespace applies by default to all enclosed elements.
Hence, all elements which do not been
included, a depth explicitly state the namespace to
which they belong are members of infinity is assumed because the method is on "DAV:" namespace schema.

8.2.4 PROPFIND Request Errors

PROPFIND requests may also fail entirely, before the server even gets
a
collection.

8.8 PUT

8.8.1 PUT for Non-Collection Resources chance to evaluate individual properties. 404 (Not Found) and 401
(Unauthorized) are possible as with every request. These are some
other notable errors.

403 Forbidden - A PUT performed server MAY reject all PROPFIND requests on an existing resource replaces the GET response
entity
collections with depth header of "Infinity", in which case it SHOULD
use this error with the resource. Properties element 'propfind-infinite-depth-forbidden'
inside the body.

8.3 PROPPATCH

The PROPPATCH method processes instructions specified in the request
body to set and/or remove properties defined on the resource may be
recomputed during PUT processing but are not otherwise affected. For
example, if a server recognizes the content type of
identified by the request body,
it may be able to automatically extract information Request-URI.

All DAV compliant resources MUST support the PROPPATCH method and
MUST process instructions that could be
profitably exposed as are specified using the
propertyupdate, set, and remove XML elements. Execution of the
directives in this method is, of course, subject to access control
constraints. DAV compliant resources SHOULD support the setting of
arbitrary dead properties.

A PUT

The request message body of a PROPPATCH method MUST contain the
propertyupdate XML element. Instruction processing MUST occur in
document order (an exception to the normal rule that would ordering is
irrelevant). Instructions MUST either all be executed or none
executed. Thus if any error occurs during processing all executed
instructions MUST be undone and a proper error result returned.
Instruction processing details can be found in the creation definition of a resource without an
appropriately scoped parent collection MUST fail the
set and remove instructions in sections 13.23 and section 13.24.

8.3.1 Status Codes for use with 207 (Multi-Status)

The following are examples of response codes one would expect to be
used in a 409
(Conflict). 207 (Multi-Status) response for this method. Note,
however, that unless explicitly prohibited any 2/3/4/5xx series

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8.8.2 PUT for Collections

As defined 2005

response code may be used in RFC2616 [8], the "PUT method requests that the enclosed
entity a 207 (Multi-Status) response.

200 (OK) - The command succeeded. As there can be stored under the supplied Request-URI." Since submission
of an entity representing a collection would implicitly encode
creation and deletion mixture of resources, this specification intentionally
does not define a transmission format for creating sets
and removes in a collection using
PUT. Instead, the MKCOL method is defined to create collections.

8.9 COPY

The COPY method creates body, a duplicate of the source resource,
identified by the Request-URI, in the destination resource,
identified by the URI in the Destination header. The Destination
header MUST be present. 201 (Created) seems inappropriate.

403 (Forbidden) - The exact behavior of the COPY method
depends on the type of the source resource.

All WebDAV compliant resources MUST support the COPY method.
However, support client, for reasons the COPY method does server chooses not guarantee to
specify, cannot alter one of the ability properties.

403 (Forbidden): The client has attempted to copy set a resource. For example, separate programs may control
resources on read- only
property, such as getetag. If returning this error, the same server. As server
SHOULD use 'read-only-property' inside the response body.

409 (Conflict) - The client has provided a result, it may value whose semantics are
not be possible to
copy a resource to a location that appears to be on the same server.

8.9.1 COPY appropriate for Non-collection Resources

When the source property.

423 (Locked) - The specified resource is not a collection the result of locked and the COPY
method client either
is the creation of not a new resource at the destination whose
state and behavior match that of the source resource as closely as
possible. Since the environment at lock owner or the destination may lock type requires a lock token to be different
than at
submitted and the source due to factors outside client did not submit it. This response SHOULD
contain the scope of control of the
server, such as 'missing-lock-token' precondition element.

507 (Insufficient Storage) - The server did not have sufficient space
to record the absence of resources required for correct
operation, it may property.

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8.3.2 Example - PROPPATCH

>>Request

PROPPATCH /bar.html HTTP/1.1
Host: www.example.com
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:Z="http://www.w3.com/standards/z39.50">
<D:response>
<D:href>http://www.example.com/bar.html</D:href>
<D:propstat>
<D:prop><Z:Authors/></D:prop>
<D:status>HTTP/1.1 424 Failed Dependency</D:status>
</D:propstat>
<D:propstat>
<D:prop><Z:Copyright-Owner/></D:prop>
<D:status>HTTP/1.1 409 Conflict</D:status>
</D:propstat>
<D:responsedescription> Copyright Owner can not be possible deleted or
altered.</D:responsedescription>
</D:response>
</D:multistatus>

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In this example, the client requests the server to completely duplicate set the
behavior value of
the resource at "Authors" property in the destination. Subsequent alterations "http://www.w3.com/standards/z39.50/"
namespace, and to remove the destination resource will not modify property "Copyright-Owner" in the source resource.
Subsequent alterations to
"http://www.w3.com/standards/z39.50/" namespace. Since the source resource will
Copyright-Owner property could not modify the
destination resource.

8.9.2 COPY for Properties

After a successful COPY invocation, all dead properties on the source
resource MUST be duplicated on removed, no property
modifications occur. The 424 (Failed Dependency) status code for the destination resource, along with
all properties as appropriate. Live properties described in
Authors property indicates this
document SHOULD be duplicated as identically behaving live properties
at the destination resource, but action would have succeeded if it
were not necessarily with for the same
values. If a property cannot be copied live, then its value MUST be
duplicated, octet-for-octet, in an identically named, dead property
on conflict with removing the destination resource.

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A COPY operation creates a new resource, much like a PUT operation
does. Live properties which are related to resource creation (such
as creationdate) should have their values set accordingly.

8.9.3 COPY for Collections Copyright-Owner property.

8.4 MKCOL Method

The COPY MKCOL method on a collection without is used to create a Depth header new collection. All WebDAV
compliant resources MUST act as if
a Depth header with value "infinity" was included. A client may
submit a Depth header on a COPY on support the MKCOL method.

MKCOL creates a new collection with a value of "0"
or "infinity". Servers MUST support resource at the "0" and "infinity" Depth
header behaviors on WebDAV-compliant resources.

A COPY of depth infinity instructs that location specified by
the Request-URI. If the collection resource identified by the Request-URI is to be copied to the location
identified by
non-null then the URI in MKCOL MUST fail. During MKCOL processing, a server
MUST make the Destination header, and all its internal
member resources are to be copied to Request-URI a location relative to it,
recursively through all levels member of its parent collection, unless
the collection hierarchy.

A COPY of "Depth: 0" only instructs that Request-URI is "/". If no such ancestor exists, the collection and its
properties but not resources identified by its internal member URLs,
are to be copied.

Any headers included with a COPY method MUST be applied in processing every
resource to be copied with the exception of the Destination header.

The Destination header only specifies the destination URI for the
Request-URI.
fail. When applied to members of the MKCOL operation creates a new collection identified by
the Request-URI the value of Destination is to be modified to reflect
the current location in resource,
all ancestors MUST already exist, or the hierarchy. So, method MUST fail with a 409
(Conflict) status code. For example, if the Request-URI a request to create
collection /a/b/c/d/ is /a/
with Host header value http://example.com/ made, and /a/b/c/ does not exist, the Destination request
must fail.

When MKCOL is
http://example.com/b/ then invoked without a request body, the newly created
collection SHOULD have no members.

A MKCOL request message may contain a message body. The precise
behavior of a MKCOL request when http://example.com/a/c/d the body is processed
it must use present is undefined,
but limited to creating collections, members of a Destination collection, bodies
of http://example.com/b/c/d.

When members and properties on the COPY method has completed processing collections or members. If the
server receives a MKCOL request entity type it does not support or
understand it MUST have created respond with a
consistent namespace at 415 (Unsupported Media Type) status
code. If the destination (see Section 8.7.2for server decides to reject the
definition request based on the
presence of namespace consistency). However, if an error occurs
while copying entity or the type of an internal collection, entity, it should use the server 415
(Unsupported Media Type) status code.

8.4.1 MKCOL Status Codes

Responses from a MKCOL request MUST NOT copy any
resources identified by members of this collection (i.e., the server
must skip this subtree), be cached as this would create an inconsistent
namespace. After detecting an error, the COPY operation SHOULD try
to finish as much MKCOL has non-
idempotent semantics.

201 (Created) - The collection was created.

403 (Forbidden) - This indicates at least one of the original copy operation as possible (i.e., two conditions: 1)
the server should still attempt to copy other subtrees and their
members, that are does not descendents allow the creation of an error-causing collection).

So, for example, if an infinite depth copy operation is performed on
collection /a/, which contains collections /a/b/ and /a/c/, and an
error occurs copying /a/b/, an attempt should still be made to copy /
a/c/. Similarly, after encountering an error copying a non- at the given
location in its namespace, or 2) the parent collection of the

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collection resource as part of 2005

Request-URI exists but cannot accept members.

405 (Method Not Allowed) - MKCOL can only be executed on an infinite depth copy, unmapped
URL.

409 (Conflict) - A collection cannot be made at the Request-URI until
one or more intermediate collections have been created. The server
SHOULD try to finish as much of the original copy operation as
possible.

If an error in executing
MUST NOT create those intermediate collections automatically.

415 (Unsupported Media Type) - The server does not support the COPY method occurs with a resource other
than
request type of the body.

507 (Insufficient Storage) - The resource identified in the Request-URI then the response
MUST be a 207 (Multi-Status), and does not have sufficient
space to record the URL state of the resource causing the
failure MUST appear with after the specific error.

The 424 (Failed Dependency) status code SHOULD NOT be returned in the
207 (Multi-Status) response from a COPY execution of this
method. These responses can
be safely omitted because the client will know that

8.4.2 Example - MKCOL

This example creates a collection called /webdisc/xfiles/ on the progeny
server www.example.com.

>>Request

MKCOL /webdisc/xfiles/ HTTP/1.1
Host: www.example.com

>>Response

HTTP/1.1 201 Created

8.5 GET, HEAD for Collections

The semantics of a
resource could not be copied GET are unchanged when applied to a collection,
since GET is defined as, "retrieve whatever information (in the client receives form
of an error for
the parent. Additionally 201 (Created)/204 (No Content) status codes
SHOULD NOT be returned as values in 207 (Multi-Status) responses from
COPY methods. They, too, can be safely omitted because they are entity) is identified by the
default success codes.

8.9.4 COPY and Request-URI" [RFC2616]. GET when
applied to a collection may return the Overwrite Header

If contents of an "index.html"
resource, a resource exists at human-readable view of the destination and contents of the Overwrite header collection, or
something else altogether. Hence it is
"T" then prior to performing the copy possible that the server MUST perform result of a
DELETE with "Depth: infinity"
GET on the destination resource. If the
Overwrite header is set a collection will bear no correlation to "F" then the operation will fail.

8.9.5 Status Codes

201 (Created) - The source resource was successfully copied. The
copy operation resulted in membership of the creation
collection.

Similarly, since the definition of HEAD is a new resource.

204 (No Content) - The source resource was successfully copied to GET without a
pre-existing destination resource.

207 (Multi-Status) - Multiple resources were to be affected by the
COPY, but errors on some of them prevented the operation from taking
place. Specific error messages, together with the most appropriate
of the source and destination URLs, appear in response
message body, the body semantics of the multi-
status response. E.g. if a destination resource was locked and
could not be overwritten, then the destination resource URL appears
with the 423 (Locked) status.

403 (Forbidden) - The operation is forbidden. Possibly this is
because the source and destination resources HEAD are the same resource.

409 (Conflict) - A resource cannot be created at the destination
until one or more intermediate collections have been created. The
server MUST NOT create those intermediate collections automatically. unmodified when applied to
collection resources.

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412 (Precondition Failed) - A precondition failed, e.g. 2005

8.6 POST for Collections

Since by definition the
Overwrite header actual function performed by POST is "F" and
determined by the state of server and often depends on the destination resource is
non-null.

423 (Locked) - The destination particular
resource, or resource within the
destination collection, was locked. This response SHOULD contain the
'missing-lock-token' precondition element.

502 (Bad Gateway) - This may occur behavior of POST when the destination is on another
server, repository or namespace. Either the source namespace does
not support copying to the destination namespace, or the destination
namespace refuses applied to accept collections cannot be
meaningfully modified because it is largely undefined. Thus the resource. The client may wish
semantics of POST are unmodified when applied to try
GET/PUT and PROPFIND/PROPPATCH instead.

507 (Insufficient Storage) - The destination resource does not have
sufficient space to record the state of the a collection.

8.7 DELETE

Locks rooted on a resource after the
execution MUST be destroyed in a successful DELETE
of this method.

8.9.6 COPY Examples

This example shows resource http://www.ics.uci.edu/~fielding/
index.html being copied that resource.

8.7.1 DELETE for Non-Collection Resources

When a client issues a DELETE request to a Request-URI mapping to a
non-collection resource, if the location http://www.ics.uci.edu/users/
f/fielding/index.html. The 204 (No Content) status code indicates
the existing resource at the destination was overwritten.

COPY with Overwrite

>>Request

COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html

>>Response

HTTP/1.1 204 No Content

The following example shows the same copy operation being performed,
but with the Overwrite header set to "F." A response of 412
(Precondition Failed) is returned because successful the destination resource
has server
MUST remove that mapping. Thus, after a non-null state.

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COPY with No Overwrite

>>Request

COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html
Overwrite: F

>>Response

HTTP/1.1 412 Precondition Failed

Example - COPY successful DELETE operation
(and in the absence of other actions) a Collection

>>Request

COPY /container/ HTTP/1.1
Host: www.example.com
Destination: http://www.example.com/othercontainer/
Depth: infinity

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>

<d:multistatus xmlns:d="DAV:">
<d:response>
<d:href>http://www.example.com/othercontainer/R2/</d:href>
<d:status>HTTP/1.1 423 Locked</d:status>
</d:response>
</d:multistatus>

The Depth header is unnecessary as subsequent GET/HEAD/PROPFIND
request to the default behavior of COPY target Request-URI MUST return 404 (Not Found).

8.7.2 DELETE for Collections

The DELETE method on a collection is to MUST act as if a "Depth: infinity"
header had been
submitted. In this example most of the resources, along with the
collection, were copied successfully. However the collection R2
failed because the destination R2 is locked. Because there was an
error copying R2, none of R2's members were copied. However no
errors were listed for those members due to the error minimization
rules.

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8.10 MOVE

The MOVE operation used on it. A client MUST NOT submit a non-collection resource is the logical
equivalent of Depth header with
a copy (COPY), followed by consistency maintenance
processing, followed by DELETE on a delete of collection with any value but infinity.

DELETE instructs that the source, where collection specified in the Request-URI and
all three
actions resources identified by its internal member URLs are performed atomically. The consistency maintenance step
allows the server to perform updates caused be
deleted.

If any resource identified by the move, such as
updating a member URL cannot be deleted then all URLs other than the Request-URI which identify the
source resource, to point to the new destination resource.
Consequently,
of the Destination header member's ancestors MUST NOT be present on all MOVE
methods and deleted, so as to maintain
namespace consistency.

Any headers included with DELETE MUST follow all COPY requirements for the COPY part of be applied in processing every
resource to be deleted.

When the MOVE method. All WebDAV compliant resources DELETE method has completed processing it MUST support result in a
consistent namespace.

If an error occurs deleting an internal resource (a resource other
than the
MOVE method. However, support for resource identified in the MOVE method does not guarantee Request-URI) then the ability to move response
can be a resource 207 (Multi-Status). Multi-Status is used here to a particular destination. indicate
which internal resources could NOT be deleted, including an error
code which should help the client understand which resources caused
the failure. For example, separate programs may actually control different sets of
resources on the same server. Therefore, it may not be possible to
move Multi-Status body could include a
response with status 423 (Locked) if an internal resource within was locked.

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The server MAY return a namespace that appears to belong to the same
server.

If 4xx status response, rather than a resource exists at the destination, Multi-
Status, if the destination resource
will request failed.

424 (Failed Dependency) errors SHOULD NOT be deleted as a side-effect of the MOVE operation, subject to
the restrictions of the Overwrite header.

8.10.1 MOVE for Properties

Live properties described in this document MUST the 207 (Multi-
Status). They can be moved along with safely left out because the resource, such client will know
that the ancestors of a resource has identically behaving live
properties at the destination resource, but not necessarily with the
same values. If the live properties will could not work the same way at
the destination, the server MUST fail be deleted when the request (the client can
perform COPY then DELETE if it wants a MOVE to work that badly).
This can mean that the server reports
receives an error for the live property as "Not
Found" if that's ancestor's progeny. Additionally 204 (No
Content) errors SHOULD NOT be returned in the most appropriate behavior 207 (Multi- Status).
The reason for that live property
at this prohibition is that 204 (No Content) is the destination, as long as
default success code.

8.7.3 Example - DELETE

>>Request

DELETE /container/ HTTP/1.1
Host: www.example.com

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

In this example the live property attempt to delete
http://www.example.com/container/resource3 failed because it is still supported
locked, and no lock token was submitted with the same semantics.

MOVE is frequently used by clients to rename a file without changing
its parent collection, so it's not appropriate request.
Consequently, the attempt to reset live
properties which are set at resource creation. For example, delete http://www.example.com/container/
also failed. Thus the
creationdate property value SHOULD remain client knows that the same after a MOVE.

Dead properties attempt to delete
http://www.example.com/container/ must have also failed since the
parent can not be moved along with deleted unless its child has also been deleted.
Even though a Depth header has not been included, a depth of infinity
is assumed because the resource.

8.10.2 MOVE method is on a collection.

8.8 PUT

8.8.1 PUT for Collections Non-Collection Resources

A MOVE with "Depth: infinity" instructs that the collection
identified by the Request-URI be moved to PUT performed on an existing resource replaces the address specified in GET response

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the Destination header, and all resources identified by its internal
member URLs are to be moved to locations relative to it, recursively
through all levels 2005

entity of the collection hierarchy.

The MOVE method resource. Properties defined on a collection MUST act as if a "Depth: infinity"
header was used on it. the resource may be
recomputed during PUT processing but are not otherwise affected. For
example, if a server recognizes the content type of the request body,
it may be able to automatically extract information that could be
profitably exposed as properties.

A client PUT that would result in the creation of a resource without an
appropriately scoped parent collection MUST NOT submit fail with a Depth header on 409
(Conflict).

8.8.2 PUT for Collections

As defined in RFC2616 [7], the "PUT method requests that the enclosed
entity be stored under the supplied Request-URI." Since submission
of an entity representing a
MOVE on collection would implicitly encode
creation and deletion of resources, this specification intentionally
does not define a transmission format for creating a collection with any value but "infinity".

Any headers included with MOVE MUST using
PUT. Instead, the MKCOL method is defined to create collections. A
PUT request to an existing collection MAY be applied treated as an error (405
Method Not Allowed).

8.9 COPY

The COPY method creates a duplicate of the source resource identified
by the Request-URI, in processing every the destination resource to be moved with identified by the exception of URI
in the Destination header. The behavior of the Destination header is MUST be present.
The exact behavior of the same as given for COPY method depends on collections.

When the MOVE method has completed processing it MUST have created a
consistent namespace at both type of the
source and destination (see section
5.1 for the definition resource. The state of namespace consistency). However, if an
error occurs while moving an internal collection, the resource to be copied is fixed at
the point the server MUST NOT
move any resources identified by members of the failed collection
(i.e., begins processing the server must skip COPY request.

All WebDAV compliant resources MUST support the error-causing subtree), as this would
create an inconsistent namespace. In this case, after detecting COPY method.
However, support for the
error, COPY method does not guarantee the move operation SHOULD try ability
to finish as much of copy a resource. For example, separate programs may control
resources on the
original move as same server. As a result, it may not be possible (i.e., the server should still attempt to
move other subtrees and the resources identified by their members,
copy a resource to a location that are not descendents of an error-causing collection). So, appears to be on the same server.

8.9.1 COPY for
example, if an infinite depth move Non-collection Resources

When the source resource is performed on collection /a/,
which contains collections /a/b/ and /a/c/, and an error occurs
moving /a/b/, an attempt should still be made to try moving /a/c/.
Similarly, after encountering an error moving not a non- collection
resource as part of an infinite depth move, the server SHOULD try to
finish as much result of the original move operation as possible.

If an error occurs with COPY
method is the creation of a new resource other than at the destination whose
state and behavior match that of the source resource identified
in as closely as
possible. Since the Request-URI then environment at the response MUST destination may be a 207 (Multi-Status),
and different
than at the errored resource's URL MUST appear with source due to factors outside the specific error.

The 424 (Failed Dependency) status code SHOULD NOT be returned in the
207 (Multi-Status) response from a MOVE method. These errors can be
safely omitted because scope of control of the client will know that
server, such as the progeny absence of a
resource could not be moved when the client receives an error resources required for the
parent. Additionally 201 (Created)/204 (No Content) responses SHOULD
NOT be returned as values in 207 (Multi-Status) responses from a
MOVE. These responses can correct
operation, it may not be safely omitted because they are possible to completely duplicate the
default success codes.

8.10.3 MOVE and
behavior of the Overwrite Header

If a resource exists at the destination. Subsequent alterations
to the destination and resource will not modify the Overwrite header is
"T" then prior source resource.
Subsequent alterations to performing the move source resource will not modify the server MUST perform a

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DELETE with "Depth: infinity" on the 2005

destination resource. If the
Overwrite header is set to "F" then the operation will fail.

8.10.4 Status Codes

201 (Created) - The source resource was successfully moved, and

8.9.2 COPY for Properties

After a new
resource was created at successful COPY invocation, all dead properties on the destination.

204 (No Content) - The source
resource was successfully moved to a
pre-existing destination resource.

207 (Multi-Status) - Multiple resources were to MUST be affected by the
MOVE, but errors duplicated on some of them prevented the operation from taking
place. Specific error messages, together with the most appropriate
of the source and destination URLs, appear resource, along with
all properties as appropriate. Live properties described in this
document SHOULD be duplicated as identically behaving live properties
at the body of destination resource, but not necessarily with the multi-
status response. E.g. if same
values. If a source resource was locked and could not property cannot be moved, copied live, then its value MUST be
duplicated, octet-for-octet, in an identically named, dead property
on the source resource URL appears with the 423 (Locked)
status.

403 (Forbidden) - The source and destination resources are the same.

409 (Conflict) - resource.

A COPY operation creates a new resource, much like a PUT operation
does. Live properties which are related to resource cannot be created at the destination
until one or more intermediate collections creation (such
as creationdate) should have been created. their values set accordingly.

8.9.3 COPY for Collections

The
server COPY method on a collection without a Depth header MUST NOT create those intermediate collections automatically.
Or, the server act as if
a Depth header with value "infinity" was unable to preserve the behavior included. A client may
submit a Depth header on a COPY on a collection with a value of "0"
or "infinity". Servers MUST support the live
properties "0" and still move "infinity" Depth
header behaviors on WebDAV-compliant resources.

A COPY of depth infinity instructs that the collection resource
identified by the Request-URI is to be copied to the destination (see
'live-properties-not-preserved' postcondition).

412 (Precondition Failed) Ș A condition failed, e.g. location
identified by the Overwrite
header is "F" URI in the Destination header, and all its internal
member resources are to be copied to a location relative to it,
recursively through all levels of the state collection hierarchy. Servers
should of course avoid infinite recursion, and can do so by copying
the destination resource is non-null.

423 (Locked) - The source or resource as it existed at the destination resource, or some point where processing
started.

A COPY of "Depth: 0" only instructs that the collection and its
properties but not resources identified by its internal member URLs,
are to be copied.

Any headers included with a COPY MUST be applied in processing every
resource within to be copied with the source or destination collection, was locked.
This response SHOULD contain exception of the 'missing-lock-token' precondition
element.

502 (Bad Gateway) - This may occur when Destination header.

The Destination header only specifies the destination is on another
server and URI for the destination server refuses
Request-URI. When applied to accept members of the resource.
This could also occur when collection identified by
the destination is on another sub-section
of Request-URI the same server namespace.

8.10.5 Examples

This example shows resource http://www.ics.uci.edu/~fielding/
index.html being moved value of Destination is to be modified to reflect
the current location http://www.ics.uci.edu/users/
f/fielding/index.html. The contents of in the destination resource
would have been overwritten hierarchy. So, if the destination resource had been
non-null. In this case, since there was nothing at Request-URI is /a/
with Host header value http://example.com/ and the destination Destination is
http://example.com/b/ then when http://example.com/a/c/d is processed
it must use a Destination of http://example.com/b/c/d.

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resource, 2005

When the response code is 201 (Created).

MOVE of COPY method has completed processing it MUST have created a Non-Collection

>>Request

MOVE /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html

>>Response

HTTP/1.1 201 Created
Location: http://www.ics.uci.edu/users/f/fielding/index.html

MOVE
consistent namespace at the destination (see Section 8.7.2for the
definition of a Collection

>>Request

MOVE /container/ HTTP/1.1
Host: www.example.com
Destination: http://www.example.com/othercontainer/
Overwrite: F
If: (<opaquelocktoken:fe184f2e-6eec-41d0-c765-01adc56e6bb4>)
(<opaquelocktoken:e454f3f3-acdc-452a-56c7-00a5c91e4b77>)

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<d:multistatus xmlns:d='DAV:'>
<d:response>
<d:href>http://www.example.com/othercontainer/C2/</d:href>
<d:status>HTTP/1.1 423 Locked</d:status>
</d:response>
</d:multistatus>

In this example namespace consistency). However, if an error occurs
while copying an internal collection, the client has submitted a number server MUST NOT copy any
resources identified by members of lock tokens with this collection (i.e., the request. A lock token will need to be submitted for every
resource, both source and destination, anywhere in server
must skip this subtree), as this would create an inconsistent
namespace. After detecting an error, the scope COPY operation SHOULD try
to finish as much of the
method, that is locked. In this case the proper lock token was not
submitted for original copy operation as possible (i.e.,
the destination http://www.example.com/othercontainer/
C2/. This means server should still attempt to copy other subtrees and their
members, that the resource /container/C2/ could are not be moved.
Because there was an error moving /container/C2/, none descendents of /container/

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C2's members were moved. However no errors were listed an error-causing collection).

So, for those
members due example, if an infinite depth copy operation is performed on
collection /a/, which contains collections /a/b/ and /a/c/, and an
error occurs copying /a/b/, an attempt should still be made to the copy
/a/c/. Similarly, after encountering an error minimization rules. User agent
authentication has previously occurred via copying a mechanism outside non-
collection resource as part of an infinite depth copy, the
scope server
SHOULD try to finish as much of the HTTP protocol, in original copy operation as
possible.

If an underlying transport layer.

8.11 LOCK Method

The following sections describe error in executing the LOCK method, which is used to
take out COPY method occurs with a lock of any access type and to refresh an existing lock.
These sections on resource other
than the LOCK method describe only those semantics that
are specific to resource identified in the LOCK method Request-URI then the response
MUST be a 207 (Multi-Status), and are independent of the access
type URL of the lock being requested.

Any resource which supports causing the LOCK method MUST, at minimum, support
failure MUST appear with the XML request and specific error.

The 424 (Failed Dependency) status code SHOULD NOT be returned in the
207 (Multi-Status) response formats defined herein.

A LOCK method invocation to an unlocked resource creates from a lock on
the resource identified by COPY method. These responses can
be safely omitted because the Request-URI, which becomes client will know that the root progeny of
the lock. Lock method requests to create a new lock MUST have a XML
request body which contains
resource could not be copied when the client receives an owner XML element and other
information error for this lock request. The server MUST preserve the
information provided by
the client parent. Additionally 201 (Created)/204 (No Content) status codes
SHOULD NOT be returned as values in 207 (Multi-Status) responses from
COPY methods. They, too, can be safely omitted because they are the owner field when
default success codes.

8.9.4 COPY and the lock
information is requested. The LOCK request MAY have Overwrite Header

If a Timeout
header.

Clients MUST assume that locks may arbitrarily disappear resource exists at any time,
regardless of the value given in the Timeout header. The Timeout destination and the Overwrite header only indicates is
"T" then prior to performing the behavior of copy the server if extraordinary
circumstances do not occur. For example, a sufficiently privileged
user may remove a lock at any time or the system may crash in such MUST perform a
way that it loses
DELETE with "Depth: infinity" on the record of destination resource. If the lock's existence. The response
MUST contain
Overwrite header is set to "F" then the value of operation will fail.
(Extensions to WebDAV might not follow this rule to the lockdiscovery property in letter but
must consider backwards compatibility with clients that expect COPY
to work this way.)

Interoperability testing has shown that some clients expect a prop XML
element.

A success response
collection COPY to actually do a LOCK request MUST include the Lock-Token
response header with the token associated merge if a destination collection
exists. That behavior is appropriate for file system folders but not
necessarily for other data objects modelled as collections. Thus,
implementors are urged to comply with the new lock, standard language above,

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and MUST
contain leave clients to perform a body with the value of the 'lockdiscovery' property. Note
that the Lock-Token header would not be returned in manual merge if that's the response for
a successful refresh LOCK request because expected
behavior when copying a new lock collection over another collection.

8.9.5 Status Codes

201 (Created) - The source resource was not created. successfully copied. The scope of a lock is
copy operation resulted in the entire state creation of the resource, including
its body and associated properties. As a result, a lock on a
resource MUST also lock the resource's properties.

For collections, new resource.

204 (No Content) - The source resource was successfully copied to a lock also affects the ability
pre-existing destination resource.

207 (Multi-Status) - Multiple resources were to add or remove
members. The nature be affected by the
COPY, but errors on some of them prevented the effect depends upon operation from taking
place. Specific error messages, together with the type of access
control involved. This means that if a collection is locked, its
lock-token is required in all these cases:

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o DELETE a collection's direct internal member
o MOVE a member out most appropriate
of the collection
o MOVE a member into the collection, unless it overwrites a pre-
existing member
o MOVE to rename it within a collection,
o COPY a member into a collection, unless it overwrites a pre-
existing member
o PUT or MKCOL request which would create a new member.

The collection's lock token is required source and destination URLs, appear in addition to the lock token
on body of the internal member itself, multi-
status response. E.g. if it exists.

The interaction of a LOCK destination resource was locked and could
not be overwritten, then the destination resource URL appears with various methods
the 423 (Locked) status.

403 (Forbidden) - The operation is dependent upon forbidden. Possibly this is
because the
lock type. However, independent of lock type, a successful DELETE of
a source and destination resources are the same resource.

409 (Conflict) - A resource MUST cause all of its direct locks to cannot be removed.

8.11.1 Refreshing Locks

A lock is refreshed by sending a LOCK request without a body to a
resource within the scope of the lock. A LOCK request to refresh a
lock must specify which lock to refresh by using created at the Lock-Token
header with a single lock token (only destination
until one lock may be refreshed at a
time). This request or more intermediate collections have been created. The
server MUST NOT contain a body, but it may contain a
Timeout header. create those intermediate collections automatically.

412 (Precondition Failed) - A server MAY accept precondition failed, e.g. the Timeout Overwrite
header to change the
duration remaining on the lock to is "F" and the new value. A server MUST
ignore state of the Depth header on a LOCK refresh, and destination resource is non-null.

423 (Locked) - The destination resource, or resource within the client
destination collection, was locked. This response SHOULD NOT
send contain the Depth header
'missing-lock-token' precondition element.

502 (Bad Gateway) - This may occur when the destination is on a LOCK refresh as another
server, repository or namespace. Either the server will source namespace does
not
convert support copying to the lock destination namespace, or confirm the depth.

If destination
namespace refuses to accept the resource. The client may wish to try
GET/PUT and PROPFIND/PROPPATCH instead.

507 (Insufficient Storage) - The destination resource has other (shared) locks, those locks are unaffected
by a lock refresh. Additionally, those locks do does not prevent the
named lock from being refreshed.

Note that in RFC2518, clients were indicated through have
sufficient space to record the example in state of the text to use resource after the If header to specify what lock to refresh (rather
than the Lock-Token header). Servers are encouraged to continue to
support
execution of this as well as method.

8.9.6 COPY Examples

This example shows resource
http://www.ics.uci.edu/~fielding/index.html being copied to the Lock-Token header.

8.11.2 Depth and Locking
location http://www.ics.uci.edu/users/f/fielding/index.html. The Depth header may be used 204

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(No Content) status code indicates the existing resource at the
destination was overwritten.

COPY with Overwrite

>>Request

COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html

>>Response

HTTP/1.1 204 No Content

The following example shows the LOCK method. Values other than
0 or infinity MUST NOT be used same copy operation being performed,
but with the Depth Overwrite header on a LOCK
method. All resources that support the LOCK method MUST support the
Depth header. set to "F." A Depth header response of value 0 means to just lock 412
(Precondition Failed) is returned because the destination resource specified
by the Request-URI.
has a non-null state.

COPY with No Overwrite

>>Request

COPY /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html
Overwrite: F

>>Response

HTTP/1.1 412 Precondition Failed

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If the 2005

Example - COPY of a Collection

>>Request

COPY /container/ HTTP/1.1
Host: www.example.com
Destination: http://www.example.com/othercontainer/
Depth: infinity

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>

<d:multistatus xmlns:d="DAV:">
<d:response>
<d:href>http://www.example.com/othercontainer/R2/</d:href>
<d:status>HTTP/1.1 423 Locked</d:status>
</d:response>
</d:multistatus>

The Depth header is set to infinity then unnecessary as the resource specified in default behavior of COPY on a
collection is to act as if a "Depth: infinity" header had been
submitted. In this example most of the Request-URI resources, along with all its internal members, all the way down
collection, were copied successfully. However the hierarchy, are to be locked. A successful result MUST return a
single lock token which represents all collection R2
failed because the resources that have been destination R2 is locked. If Because there was an UNLOCK is successfully executed
error copying R2, none of R2's members were copied. However no
errors were listed for those members due to the error minimization
rules.

8.10 MOVE

The MOVE operation on this token, a non-collection resource is the logical
equivalent of a copy (COPY), followed by consistency maintenance
processing, followed by a delete of the source, where all
associated resources three
actions are unlocked. If performed atomically. The consistency maintenance step
allows the lock cannot be granted server to perform updates caused by the move, such as
updating all resources, a 207 (Multi-Status) status code MUST be returned with
a response entity body containing a multistatus XML element
describing URLs other than the Request-URI which resource(s) prevented identify the lock from being granted.
Hence, partial success is not an option. Either
source resource, to point to the entire hierarchy
is locked or no resources are locked.

If no Depth new destination resource.
Consequently, the Destination header is submitted MUST be present on a LOCK request then all MOVE
methods and MUST follow all COPY requirements for the request COPY part of
the MOVE method. All WebDAV compliant resources MUST act as if a "Depth:infinity" had been submitted.

8.11.3 Locking Unmapped URLs

A successful LOCK support the
MOVE method. However, support for the MOVE method MUST result in does not guarantee
the creation of an empty ability to move a resource which is locked (and which is to a particular destination.

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For example, separate programs may actually control different sets of
resources on the same server. Therefore, it may not be possible to
move a collection), when resource within a namespace that appears to belong to the same
server.

If a resource did not previously exist exists at that URL. Later on, the lock
may go away but destination, the empty destination resource remains. Empty resources MUST
then appear
will be deleted as a side-effect of the MOVE operation, subject to
the restrictions of the Overwrite header.

8.10.1 MOVE for Properties

Live properties described in PROPFIND responses including this document MUST be moved along with
the resource, such that URL in the response
scope. A resource has identically behaving live
properties at the destination resource, but not necessarily with the
same values. If the live properties will not work the same way at
the destination, the server MUST respond successfully to a GET fail the request to an
empty resource, either by using a 204 No Content response, or by
using 200 OK with (the client can
perform COPY then DELETE if it wants a Content-Length header indicating zero length and
no Content-Type.

8.11.4 Lock Compatibility Table

The table below describes MOVE to work that badly).
This can mean that the server reports the live property as "Not
Found" if that's the most appropriate behavior for that occurs when a lock
request live property
at the destination, as long as the live property is made on a resource.

Current State Shared Lock Request Exclusive Lock Request
--------------------------------------------------------------------
None True True
Shared Lock True False
Exclusive Lock False False*

Legend: True = lock may be granted. False = lock MUST NOT be
granted. *=It still supported
with the same semantics.

MOVE is illegal for frequently used by clients to rename a principal file without changing
its parent collection, so it's not appropriate to request reset live
properties which are set at resource creation. For example, the
creationdate property value SHOULD remain the same lock
twice.

The current lock state of after a resource is given MOVE.

Dead properties must be moved along with the resource.

8.10.2 MOVE for Collections

A MOVE with "Depth: infinity" instructs that the collection
identified by the Request-URI be moved to the address specified in
the leftmost column, Destination header, and lock requests all resources identified by its internal
member URLs are listed in the first row. The intersection to be moved to locations relative to it, recursively
through all levels of a
row and column gives the result of collection hierarchy.

The MOVE method on a lock request. For example, collection MUST act as if a
shared lock is held "Depth: infinity"
header was used on it. A client MUST NOT submit a resource, and an exclusive lock is

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requested, the table entry is "false", indicating the lock must not
be granted.

8.11.5 LOCK responses

200 (OK) - The lock request succeeded and the Depth header on a
MOVE on a collection with any value of the
lockdiscovery property is but "infinity".

Any headers included with MOVE MUST be applied in the body.

409 (Conflict) - A processing every
resource cannot to be moved with the exception of the Destination header.
The behavior of the Destination header is the same as given for COPY
on collections.

When the MOVE method has completed processing it MUST have created a
consistent namespace at both the source and destination
until one or more intermediate collections have been created. The (see section

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5.1 for the definition of namespace consistency). However, if an
error occurs while moving an internal collection, the server MUST NOT create those intermediate collections automatically.

412 (Precondition Failed) - The included lock token was not
enforceable on this resource or
move any resources identified by members of the server could not satisfy failed collection
(i.e., the
request in server must skip the lockinfo XML element.

423 (Locked) - The resource is locked already. For consistency's
sake, error-causing subtree), as this response SHOULD contain would
create an inconsistent namespace. In this case, after detecting the 'missing-lock-token'
precondition element.

400 (Bad Request), with 'request-uri-must-match-lock-token'
precondition - The LOCK request was made with a Lock-Token header,
indicating that
error, the client wishes move operation SHOULD try to refresh the given lock.
However, finish as much of the Request-URI did not fall within
original move as possible (i.e., the scope of server should still attempt to
move other subtrees and the lock resources identified by the token. The lock may have a scope their members,
that does are not
include the Request-URI, or the lock could have disappeared, or the
token may be invalid.

8.11.6 Example - Simple Lock Request

>>Request

LOCK /workspace/webdav/proposal.doc HTTP/1.1
Host: example.com
Timeout: Infinite, Second-4100000000
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx
Authorization: Digest username="ejw",
realm="ejw@example.com", nonce="...",
uri="/workspace/webdav/proposal.doc",
response="...", opaque="..."

<?xml version="1.0" encoding="utf-8" ?>
<D:lockinfo xmlns:D='DAV:'>
<D:lockscope><D:exclusive/></D:lockscope>
<D:locktype><D:write/></D:locktype>
<D:owner>
<D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href>

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</D:owner>
</D:lockinfo>

>>Response

HTTP/1.1 200 OK
Lock-Token: <opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4>
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:prop xmlns:D="DAV:">
<D:lockdiscovery>
<D:activelock>
<D:locktype><D:write/></D:locktype>
<D:lockscope><D:exclusive/></D:lockscope>
<D:depth>infinity</D:depth>
<D:owner>
<D:href>
http://www.ics.uci.edu/~ejw/contact.html
</D:href>
</D:owner>
<D:timeout>Second-604800</D:timeout>
<D:locktoken>
<D:href>opaquelocktoken:e71d4fae-5dec-22d6-fea5-
00a0c91e6be4</D:href>
</D:locktoken>
<D:lockroot>
<D:href>http://example.com/workspace/webdav
/proposal.doc</D:href>
</D:lockroot>
</D:activelock>
</D:lockdiscovery>
</D:prop>

This example shows the successful creation descendents of an exclusive write lock error-causing collection). So, for
example, if an infinite depth move is performed on resource http://example.com/workspace/webdav/proposal.doc. The
resource http://www.ics.uci.edu/~ejw/contact.html collection /a/,
which contains contact
information for the owner collections /a/b/ and /a/c/, and an error occurs
moving /a/b/, an attempt should still be made to try moving /a/c/.
Similarly, after encountering an error moving a non- collection
resource as part of an infinite depth move, the lock. The server has SHOULD try to
finish as much of the original move operation as possible.

If an
activity-based timeout policy error occurs with a resource other than the resource identified
in place on this resource, which causes the lock to automatically be removed after 1 week (604800 seconds).
Note that Request-URI then the nonce, response, response MUST be a 207 (Multi-Status),
and opaque fields have not been
calculated in the Authorization request header.

Note that errored resource's URL MUST appear with the locktoken and lockroot href elements would not contain
any whitespace. specific error.

The line return appearing 424 (Failed Dependency) status code SHOULD NOT be returned in this document is only
for formatting.

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8.11.7 Example - Refreshing the
207 (Multi-Status) response from a Write Lock

>>Request

LOCK /workspace/webdav/proposal.doc HTTP/1.1
Host: example.com
Timeout: Infinite, Second-4100000000
Lock-Token: <opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4>
Authorization: Digest username="ejw",
realm="ejw@example.com", nonce="...",
uri="/workspace/webdav/proposal.doc",
response="...", opaque="..."

>>Response

HTTP/1.1 200 OK
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

This request would refresh MOVE method. These errors can be
safely omitted because the lock, attempting to reset client will know that the timeout
to progeny of a
resource could not be moved when the new value specified client receives an error for the
parent. Additionally 201 (Created)/204 (No Content) responses SHOULD
NOT be returned as values in 207 (Multi-Status) responses from a
MOVE. These responses can be safely omitted because they are the timeout header. Notice that
default success codes.

8.10.3 MOVE and the
client asked for an infinite time out but Overwrite Header

If a resource exists at the server choose destination and the Overwrite header is
"T" then prior to ignore

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have not been calculated in server MUST perform a
DELETE with "Depth: infinity" on the Authorization request header.

8.11.8 Example destination resource. If the
Overwrite header is set to "F" then the operation will fail.

8.10.4 Status Codes

201 (Created) - Multi-Resource Lock Request

>>Request

LOCK /webdav/ HTTP/1.1
Host: example.com
Timeout: Infinite, Second-4100000000
Depth: infinity
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx
Authorization: Digest username="ejw",
realm="ejw@example.com", nonce="...",
uri="/workspace/webdav/proposal.doc",
response="...", opaque="..."

<?xml version="1.0" encoding="utf-8" ?>
<D:lockinfo xmlns:D="DAV:">
<D:locktype><D:write/></D:locktype>
<D:lockscope><D:exclusive/></D:lockscope>
<D:owner>
<D:href>http://www.ics.uci.edu/~ejw/contact.html</D:href>
</D:owner>
</D:lockinfo>

>>Response

HTTP/1.1 The source resource was successfully moved, and a new
resource was created at the destination.

204 (No Content) - The source resource was successfully moved to a
pre-existing destination resource.

207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:">
<D:response>
<D:href>http://example.com/webdav/secret</D:href>
<D:status>HTTP/1.1 403 Forbidden</D:status>
</D:response>
<D:response>
<D:href>http://example.com/webdav/</D:href>
<D:propstat>
<D:prop><D:lockdiscovery/></D:prop>
<D:status>HTTP/1.1 424 Failed Dependency</D:status>
</D:propstat>
</D:response>
</D:multistatus> (Multi-Status) - Multiple resources were to be affected by the
MOVE, but errors on some of them prevented the operation from taking
place. Specific error messages, together with the most appropriate
of the source and destination URLs, appear in the body of the multi-

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This example shows a request for an exclusive write lock on a
collection and all its children. In this request, the client has
specified that it desires an infinite length lock, 2005

status response. E.g. if available,
otherwise a timeout of 4.1 billion seconds, if available. The
request entity body contains the contact information for source resource was locked and could not
be moved, then the
principal taking out source resource URL appears with the lock, in this case a web page URL.

The error is a 423 (Locked)
status.

403 (Forbidden) response on - The source and destination resources are the same.

409 (Conflict) - A resource http://
example.com/webdav/secret. Because this resource could not cannot be
locked, none of created at the resources were locked. Note also that the
lockdiscovery property for the Request-URI has destination
until one or more intermediate collections have been included as
required. In this example created. The
server MUST NOT create those intermediate collections automatically.
Or, the lockdiscovery property is empty which
means that there are no outstanding locks on server was unable to preserve the resource.

In this example, behavior of the nonce, response, live
properties and opaque fields have not been
calculated in the Authorization request header.

8.12 UNLOCK Method

The UNLOCK method removes still move the lock identified by resource to the lock token in destination (see 'live-
properties-not-preserved' postcondition).

412 (Precondition Failed) n A condition failed, e.g. the Lock-Token request header. The Request-URI MUST identify a
resource within Overwrite
header is "F" and the scope state of the lock. The If header destination resource is not needed
to provide non-null.

423 (Locked) - The source or the lock token although servers destination resource, or some
resource within the source or destination collection, was locked.
This response SHOULD still evaluate contain the
If header 'missing-lock-token' precondition
element.

502 (Bad Gateway) - This may occur when the destination is on another
server and treat it as a conditional header.

For a successful response to this method, the destination server MUST remove refuses to accept the
lock from resource.
This could also occur when the destination is on another sub-section
of the same server namespace.

8.10.5 Examples

This example shows resource identified by
http://www.ics.uci.edu/~fielding/index.html being moved to the Request-URI and from all
other resources included in
location http://www.ics.uci.edu/users/f/fielding/index.html. The
contents of the lock.

If all resources which destination resource would have been locked under the submitted lock
token can not be unlocked then overwritten if
the UNLOCK request MUST fail.

A successful response to an UNLOCK method does not mean that the
resource is necessarily unlocked. It means that the specific lock
corresponding to the specified token no longer exists.

Any DAV compliant destination resource which supports had been non-null. In this case, since
there was nothing at the LOCK method MUST
support destination resource, the UNLOCK method.

8.12.1 Status Codes

204 (No Content) - Normal success response

400 (Bad Request) - No lock token was provided (see
'missing-lock-token' precondition), or request was made to a
Request-URI that was not within the scope code is
201 (Created).

MOVE of the lock (see
'requesturi-must-match-lock-token' precondition). a Non-Collection

>>Request

MOVE /~fielding/index.html HTTP/1.1
Host: www.ics.uci.edu
Destination: http://www.ics.uci.edu/users/f/fielding/index.html

>>Response

HTTP/1.1 201 Created
Location: http://www.ics.uci.edu/users/f/fielding/index.html

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403 (Forbidden) - The currently authenticated principal does not have
permission to remove the lock (the server SHOULD use the
'need-privileges' precondition element).

412 (Precondition Failed) - The resource was not locked.

8.12.2 Example 2005

MOVE of a Collection

>>Request

UNLOCK /workspace/webdav/info.doc

MOVE /container/ HTTP/1.1
Host: example.com
Lock-Token: <opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7>
Authorization: Digest username="ejw",
realm="ejw@example.com", nonce="...",
uri="/workspace/webdav/proposal.doc",
response="...", opaque="..." www.example.com
Destination: http://www.example.com/othercontainer/
Overwrite: F
If: (<opaquelocktoken:fe184f2e-6eec-41d0-c765-01adc56e6bb4>)
(<opaquelocktoken:e454f3f3-acdc-452a-56c7-00a5c91e4b77>)

>>Response

HTTP/1.1 204 No Content 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

In this example, example the client has submitted a number of lock identified by tokens with
the request. A lock token
"opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7" is
successfully removed from the resource http://example.com/workspace/
webdav/info.doc. If this lock included more than just one will need to be submitted for every
resource,
the lock is removed from all resources included both source and destination, anywhere in the lock. The 204
(No Content) status code is used instead scope of 200 (OK) because there the
method, that is
no response entity body. locked. In this example, case the nonce, response, and opaque fields have proper lock token was not been
calculated
submitted for the destination
http://www.example.com/othercontainer/C2/. This means that the
resource /container/C2/ could not be moved. Because there was an
error moving /container/C2/, none of /container/C2's members were
moved. However no errors were listed for those members due to the
error minimization rules. User agent authentication has previously
occurred via a mechanism outside the scope of the HTTP protocol, in
an underlying transport layer.

8.11 LOCK Method

The following sections describe the Authorization request header. LOCK method, which is used to
take out a lock of any access type and to refresh an existing lock.
These sections on the LOCK method describe only those semantics that
are specific to the LOCK method and are independent of the access
type of the lock being requested.

Any resource which supports the LOCK method MUST, at minimum, support

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9. HTTP Headers for Distributed Authoring

All DAV headers follow 2005

the same basic formatting rules as HTTP
headers. This includes rules like line continuation XML request and how response formats defined herein.

A LOCK method invocation to
combine (or separate) multiple instances of an unlocked resource creates a lock on
the same header using
commas.

9.1 DAV Header

DAV = "DAV" ":" #( compliance-code )
compliance-code = ( "1" | "2" | "bis" | extend )
extend = Coded-URL | token

This general-header appearing in resource identified by the response indicates that Request-URI, which becomes the
resource supports root of
the DAV schema lock. Lock method requests to create a new lock MUST have a XML
request body which contains an owner XML element and protocol as specified. All DAV
compliant resources other
information for this lock request. The server MUST return preserve the DAV header on all OPTIONS
responses.

The value
information provided by the client in the owner field when the lock
information is requested. The LOCK request MAY have a comma-separated list of all compliance class
identifiers Timeout
header.

Clients MUST assume that the resource supports. Class identifiers locks may be
Coded-URLs or tokens (as defined by [RFC2616]). Identifiers can
appear in arbitrarily disappear at any order. Identifiers that are standardized through time,
regardless of the
IETF RFC process are tokens, but other identifiers SHOULD be Coded-
URLs to encourage uniqueness.

A resource must show class 1 compliance value given in the Timeout header. The Timeout
header only indicates the behavior of the server if it shows class 2 or "bis"
compliance. In general, support for one compliance class does extraordinary
circumstances do not
entail support for occur. For example, a sufficiently privileged
user may remove a lock at any other. Please refer to section 16 for more
details on compliance classes defined in this specification.

This header must also appear on responses to OPTIONS requests to time or the
special '*' Request-URI as defined system may crash in HTTP/1.1. In this case it
means such a
way that it loses the repository supports record of the named features in at least
some internal namespaces.

As an optional request header, this header allows lock's existence.

When a new lock is created, the client to
advertise compliance LOCK response:

MUST contain a body with named features. Clients need not advertise
1, 2 or bis because the value of the lockdiscovery property
in a WebDAV server currently doesn't need that
information prop XML element.

MUST include the Lock-Token response header with the token
associated with the new lock.

8.11.1 Refreshing Locks

A lock is refreshed by sending a LOCK request without a body to decide how a
resource within the scope of the lock. A LOCK request to respond refresh a
lock must specify which lock to requests defined in this
specification or in HTTP/1.1. However, future extensions refresh by using the Lock-Token
header with a single lock token (only one lock may define
client compliance codes. When used as be refreshed at a
time). This request header, MUST NOT contain a body, but it may contain a
Timeout header. A server MAY accept the DAV Timeout header MAY affect caching so this to change the
duration remaining on the lock to the new value. A server MUST
ignore the Depth header on a LOCK refresh, and the client SHOULD NOT be used on all
GET requests.

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9.2 Depth Header

Depth = "Depth" ":" ("0" | "1" | "infinity")

The
send the Depth request header is used with methods executed on resources
which could potentially have internal members to indicate whether a LOCK refresh as the
method is to be applied only to server will not
convert the resource ("Depth: 0"), to lock or confirm the depth.

If the resource and its immediate children, ("Depth: 1"), or the resource
and all its progeny ("Depth: infinity").

The Depth header is only supported if a method's definition
explicitly provides for such support.

The following rules has other (shared) locks, those locks are unaffected
by a lock refresh. Additionally, those locks do not prevent the default behavior for any method
named lock from being refreshed.

Note that
supports in RFC2518, clients were indicated through the Depth header. A method may override these defaults by
defining different behavior example in its definition.

Methods which support
the Depth text to use the If header may choose not to support all
of specify what lock to refresh (rather
than the header's values and may define, on a case by case basis, Lock-Token header). Servers are encouraged to continue to
support this as well as the
behavior of Lock-Token header.

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Note that the method if a Depth Lock-Token header is not present. For
example, be returned in the MOVE method only supports "Depth: infinity" and if response
for a successful refresh LOCK request, but the LOCK response body
MUST contain the new value for the lockdiscovery body.

8.11.2 Depth and Locking

The Depth header is not present will act as if a "Depth: infinity" header
had been applied.

Clients may be used with the LOCK method. Values other than
0 or infinity MUST NOT rely upon methods executing on members of their
hierarchies in any particular order or on the execution being atomic
unless the particular method explicitly provides such guarantees.

Upon execution, a method be used with a the Depth header will perform as much of
its assigned task as possible and then return a response specifying
what it was able to accomplish and what it failed to do.

So, for example, an attempt to COPY a hierarchy may result in some of
the members being copied and some not.

Any headers on a method LOCK
method. All resources that has a defined interaction with support the Depth
header LOCK method MUST be applied to all resources in the scope of support the method
except where alternative behavior is explicitly defined. For
example, an If-Match
Depth header.

A Depth header will have its of value applied against every
resource in the method's scope and will cause the method 0 means to fail if just lock the header fails to match.

If a resource, source or destination, within resource specified
by the scope of Request-URI.

If the method
with a Depth header is locked in such a way as set to prevent infinity then the
successful execution of resource specified in
the method, then Request-URI along with all its internal members, all the way down
the hierarchy, are to be locked. A successful result MUST return a
single lock token for which represents all the resources that
resource have been
locked. If an UNLOCK is successfully executed on this token, all
associated resources are unlocked. If the lock cannot be granted to
all resources, a 207 (Multi-Status) status code MUST be submitted returned with
a response entity body containing a multistatus XML element
describing which resource(s) prevented the request in lock from being granted.
Hence, partial success is not an option. Either the entire hierarchy
is locked or no resources are locked.

If request header.

The no Depth header only specifies the behavior of the method with

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regards to internal children. If is submitted on a resource does not have internal
children LOCK request then the Depth header request
MUST be ignored.

Please note, however, that it is always an error to submit act as if a value
for "Depth:infinity" had been submitted.

8.11.3 Locking Unmapped URLs

A successful LOCK method MUST result in the Depth header that creation of an empty
resource which is locked (and which is not allowed by the method's definition.
Thus submitting a "Depth: 1" on collection), when a COPY, even if the
resource does not
have internal members, will result in a 400 (Bad Request). The
method should fail did not because previously exist at that URL. Later on, the resource doesn't have internal
members, lock
may go away but because of the illegal value in the header.

9.3 Destination Header

Destination = "Destination" ":" ( absoluteURI )

The Destination request header specifies the URI which identifies a
destination empty resource for methods such as COPY and MOVE, which take
two URIs as parameters. Note remains. Empty resources MUST
then appear in PROPFIND responses including that the absoluteURI production is
defined URL in RFC2396 [6].

If the Destination value is an absolute URI, it may name a different
server (or different port or scheme). If the source response
scope. A server cannot
attempt a copy to the remote server, it MUST fail the request with a
502 (Bad Gateway) response. Servers MAY attempt respond successfully to copy the resource a GET request to the remote server an
empty resource, either by using PUT/PROPPATCH a 204 No Content response, or another mechanism.

9.4 Force-Authentication Header

Force-Authentication = "Force-Authentication" ":" Method

The Force-Authentication request header is used with the OPTIONS
method to specify that the client wants to be challenged for
authentication credentials to the resource identified by the
Request-URI. If present on a request to a WebDAV-compliant resource,
the server MUST respond
using 200 OK with either 401 (Unauthorized) or 501 (Not
Implemented) status code. The Method value is used for the client to
indicate what method it intends to use first on the resource
identified in the Request-URI. a Content-Length header indicating zero length and
no Content-Type.

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9.5 If Header

If = "If" ":" ( 1*No-tag-list | 1*Tagged-list)
No-tag-list = List
Tagged-list = Resource 1*List
Resource = Coded-URL
List = #( "(" List | Clause ")" )
Clause = ["Not"] State-token | State-token
State-token = Coded-URL | "[" entity-tag "]"
Coded-URL = "<" absoluteURI ">" 2005

8.11.4 Lock Compatibility Table

The If table below describes the behavior that occurs when a lock
request header is intended to have similar functionality to
the If- Match header defined in section 14.24 of RFC2616 [8].
However the If header made on a resource.

Current State Shared Lock Request Exclusive Lock Request
----------------------------------------------------------------
None True True
Shared Lock True False
Exclusive Lock False False*

Legend: True = lock may be granted. False = lock MUST NOT be
granted. *=It is intended illegal for use with any URI which
represents state information, referred to as a principal to request the same lock
twice.

The current lock state token, about of a resource as well as ETags. A typical example of a state token is a
lock token, given in the leftmost column,
and lock tokens requests are the only state tokens defined listed in this
specification. the first row. The <DAV:no-lock> state token intersection of a
row and column gives the result of a lock request. For example, if a
shared lock is held on a special token that
must never match resource, and an actual valid exclusive lock token. The purpose of this is
described in section 9.5.5.

The If header's purpose
requested, the table entry is to describe a series of state lists. If "false", indicating the state lock must not
be granted.

8.11.5 LOCK responses

200 (OK) - The lock request succeeded and the value of the
lockdiscovery property is included in the body.

409 (Conflict) - A resource to which cannot be created at the header destination
until one or more intermediate collections have been created. The
server MUST NOT create those intermediate collections automatically.

423 (Locked) - The resource is applied does not
match any of the specified state lists then locked already. For consistency's
sake, this response SHOULD contain the 'missing-lock-token'
precondition element.

h 400 (Bad Request), with 'request-uri-must-match-lock-token'
precondition - The LOCK request MUST fail was made with a 412 (Precondition Failed). If one of Lock-Token header,
indicating that the described state
lists matches client wishes to refresh the state given lock.
However, the Request-URI did not fall within the scope of the resource then lock
identified by the request may succeed. token. The server must parse the If header when it appears on any request,
evaluate all lock may have a scope that does not
include the clauses, and if Request-URI, or the conditional evaluates to false,
fail the request.

Note that the absoluteURI production is defined in RFC2396 [6].

RFC2518 originally defined the If header without comma separators.
This oversight meant that the If header couldn't be divided up among
multiple lines according to the HTTP header manipulation rules.
Servers supporting "bis" MUST be able to accept commas in If header
values. If the header has commas between tokens lock could have disappeared, or clauses, the
header can
token may be evaluated simply by removing the commas and proceeding
with the evaluation rules.

9.5.1 No-tag-list Production

The No-tag-list production describes invalid.

424 (Failed Dependency) - This may appear inside a series of state tokens and
ETags. If multiple No-tag-list productions are used then one only
needs to match the state of the resource for the method to be allowed 207 response to continue. All untagged tokens apply a
LOCK request, to the indicate that a resource identified in
the Request-URI. could not be locked because
of a failure on another resource.

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8.11.6 Example - no-tag-list production

If: (<opaquelocktoken:a-write-lock-token> ["I am an ETag"]), (["I
am another ETag"])

The previous header would require that the resource identified in the
Request-URI be locked with the specified lock token and in the state
identified by the "I am an ETag" ETag or in the state identified by
the second ETag "I am another ETag". To put the matter more plainly
one can think of the previous If header as being in the form (or (and
<opaquelocktoken:a-write-lock-token> ["I am an ETag"]) (and ["I am
another ETag"])).

9.5.2 Tagged-list Production

The tagged-list production scopes a list production. That is, it
specifies that the lists following Simple Lock Request

>>Request

>>Response

HTTP/1.1 200 OK
Lock-Token: <opaquelocktoken:e71d4fae-5dec-22d6-fea5-00a0c91e6be4>
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

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<D:href>http://example.com/workspace/webdav
/proposal.doc</D:href>
</D:lockroot>
</D:activelock>
</D:lockdiscovery>
</D:prop>

This example shows the successful creation of an exclusive write lock
on resource specification only
apply to the specified resource. http://example.com/workspace/webdav/proposal.doc. The scope of the
resource
production begins with http://www.ics.uci.edu/~ejw/contact.html contains contact
information for the list production immediately following owner of the
resource production and ends with lock. The server has an activity-
based timeout policy in place on this resource, which causes the next resource production, if
any. All clauses must lock
to automatically be evaluated. If the state of removed after 1 week (604800 seconds). Note that
the resource
named nonce, response, and opaque fields have not been calculated in
the tag does Authorization request header.

Note that the locktoken and lockroot href elements would not match contain
any of the associated state lists
then the request MUST fail with a 412 (Precondition Failed). whitespace. The same URI MUST NOT appear more than once in a resource production line return appearing in an If header.

Example - Tagged List If header

COPY /resource1 HTTP/1.1
Host: www.example.com
Destination: http://www.example.com/resource2
If: <http://www.example.com/resource1> (<locktoken:a-write-lock-
token> [W/"A weak ETag"]), (["strong ETag"]),
<http://www.bar.bar/random>(["another strong ETag"])

In this example http://www.example.com/resource1 document is being copied only
for formatting.

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8.11.7 Example - Refreshing a Write Lock

>>Request

>>Response

HTTP/1.1 200 OK
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

This request would refresh the lock, attempting to
http://www.example.com/resource2. When reset the method is first applied timeout
to http://www.example.com/resource1, resource1 must be in the state new value specified by "(<locktoken:a-write-lock-token> [W/"A weak ETag"])
(["strong ETag"])", that is, it either must be locked with a lock
token of "locktoken:a-write-lock-token" and have a weak entity tag W/
"A weak ETag" or it must have a strong entity tag "strong ETag".

That is in the only success condition since timeout header. Notice that the resource http://
www.bar.bar/random never has
client asked for an infinite time out but the method applied server choose to it (the only other
resource listed in the If header) and http://www.example.com/
resource2 is not listed in the If header. ignore

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9.5.3 Not Production

Every state token or ETag is either current, and hence describes 2005

the
state of a resource, or is not current, request. In this example, the nonce, response, and does opaque fields
have not describe been calculated in the
state of a resource. The boolean operation of matching a state token
or ETag to the current state of Authorization request header.

8.11.8 Example - Multi-Resource Lock Request

>>Request

>>Response

HTTP/1.1 207 Multi-Status
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx

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This example shows a resource thus resolves to request for an exclusive write lock on a true or
false value. The "Not" production is used to reverse
collection and all its children. In this request, the client has
specified that value.
The scope it desires an infinite length lock, if available,
otherwise a timeout of 4.1 billion seconds, if available. The
request entity body contains the not production is contact information for the state-token or entity-tag
immediately following it.

If: (Not <locktoken:write1> <locktoken:write2>)

When submitted with a request,
principal taking out the lock, in this If header requires that all
operand resources must not be locked with locktoken:write1 and must
be locked with locktoken:write2. case a web page URL.

The Not production error is particularly useful with a 403 (Forbidden) response on the "<DAV:no-lock>"
state token. The clause "Not <DAV:no-lock>" must evaluate to true.
Thus, any "OR" statement containing resource
http://example.com/webdav/secret. Because this resource could not be
locked, none of the clause "Not <DAV:no-lock>"
must resources were locked. Note also evaluate to true.

9.5.4 Matching Function

When performing If header processing, the definition of a matching
state token or entity tag is as follows.

Identifying a resource: The resource is identified by the URI along
with that the token, in tagged list production, or by
lockdiscovery property for the Request-URI in
untagged list production.

Matching entity tag: Where has been included as
required. In this example the entity tag matches an entity tag
associated with lockdiscovery property is empty which
means that there are no outstanding locks on the identified resource.

Matching state token: Where there is an exact match between

In this example, the state
token nonce, response, and opaque fields have not been
calculated in the If header and any state token on Authorization request header.

8.12 UNLOCK Method

The UNLOCK method removes the lock identified
resource. A by the lock state token is considered to match if in
the Lock-Token request header. The Request-URI MUST identify a
resource
is anywhere in within the scope of the lock.

Example - Matching lock tokens with collection locks

DELETE /specs/rfc2518.txt HTTP/1.1
Host: www.example.com
If: <http://www.example.com/specs/> (<locktoken:a-write-lock-token>)

For this example, The If header is not needed
to provide the lock token must be compared although servers SHOULD still evaluate the
If header and treat it as a conditional header.

For a successful response to this method, the identified
resource, which is server MUST remove the 'specs' collection
lock from the resource identified by the URL Request-URI and from all
other resources included in the tagged list production. lock.

If the 'specs' collection is not all resources which have been locked
or has a under the submitted lock with a different token,
token can not be unlocked then the UNLOCK request MUST fail. If the

Dusseault

A successful response to an UNLOCK method does not mean that the
resource is necessarily unlocked. It means that the specific lock
corresponding to the specified token no longer exists.

Any DAV compliant resource which supports the LOCK method MUST
support the UNLOCK method.

8.12.1 Status Codes

204 (No Content) - Normal success response (rather than 200 OK, since
200 OK would imply a response body, and an UNLOCK success response
does not normally contain a body)

400 (Bad Request) - No lock token was provided (see 'missing-lock-
token' precondition), or request was made to a Request-URI that was
not within the scope of the lock (see 'requesturi-must-match-lock-

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'specs' collection is locked (depth infinity) with that lock token,
then this request could succeed, both because the If header evaluates 2005

token' precondition).

403 (Forbidden) - The currently authenticated principal does not have
permission to true, and because the lock token for remove the lock affecting (the server SHOULD use the
affected 'need-
privileges' precondition element).

412 (Precondition Failed) - The resource has been provided. Alternatively, a request where was not locked.

8.12.2 Example

>>Request

UNLOCK /workspace/webdav/info.doc HTTP/1.1
Host: example.com
Lock-Token: <opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7>
Authorization: Digest username="ejw",
realm="ejw@example.com", nonce="...",
uri="/workspace/webdav/proposal.doc",
response="...", opaque="..."

>>Response

HTTP/1.1 204 No Content

In this example, the 'rfc2518.txt' URL is associated with lock identified by the lock token in
"opaquelocktoken:a515cfa4-5da4-22e1-f5b5-00a0451e6bf7" is
successfully removed from the resource
http://example.com/workspace/webdav/info.doc. If
header could also succeed.

9.5.5 If Header and Non-DAV Aware Proxies

Non-DAV aware proxies will not honor this lock included
more than just one resource, the If header, since they will
not understand lock is removed from all resources
included in the If header, lock. The 204 (No Content) status code is used
instead of 200 (OK) because there is no response entity body.

In this example, the nonce, response, and opaque fields have not been
calculated in the Authorization request header.

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9. HTTP requires non-understood Headers for Distributed Authoring

All DAV headers to be ignored. When communicating with HTTP/1.1 proxies, follow the
"Cache-Control: no-cache" request header MUST be used so same basic formatting rules as HTTP
headers. This includes rules like line continuation and how to
prevent the proxy from improperly trying to service the request from
its cache. When dealing with HTTP/1.0 proxies the "Pragma: no-
cache" request header MUST be used for
combine (or separate) multiple instances of the same reason.

9.6 Lock-Token header using
commas.

9.1 DAV Header

Lock-Token

DAV = "Lock-Token" "DAV" ":" #( compliance-code )
compliance-code = ( "1" | "2" | "bis" | extend )
extend = Coded-URL

The Lock-Token request header is used with the UNLOCK method to
identify the lock to be removed. The lock | token

This general-header appearing in the Lock-Token
request header MUST identify a lock response indicates that contains the
resource
identified by Request-URI supports the DAV schema and protocol as a member.

The Lock-Token response specified. All DAV
compliant resources MUST return the DAV header on all OPTIONS
responses.

The value is used with the LOCK method to
indicate the lock token created as a result comma-separated list of a successful LOCK
request to create a new lock.

9.7 Overwrite Header

Overwrite = "Overwrite" ":" ("T" | "F")

The Overwrite request header specifies whether the server should
overwrite all compliance class
identifiers that the state of a non-null destination resource during a COPY supports. Class identifiers may be
Coded-URLs or MOVE. A value of "F" states tokens (as defined by [RFC2616]). Identifiers can
appear in any order. Identifiers that are standardized through the server
IETF RFC process are tokens, but other identifiers SHOULD be Coded-
URLs to encourage uniqueness.

A resource must not perform the
COPY or MOVE operation show class 1 compliance if the state of the destination resource is
non-null. If the overwrite header is it shows class 2 or "bis"
compliance. In general, support for one compliance class does not included
entail support for any other. Please refer to section 16 for more
details on compliance classes defined in a COPY or MOVE
request then the resource MUST treat this specification.

This header must also appear on responses to OPTIONS requests to the request
special '*' Request-URI as if defined in HTTP/1.1. In this case it has an
overwrite header of value "T". While the Overwrite header appears to
duplicate
means that the functionality of repository supports the If-Match: * named features in at least
some internal namespaces.

As an optional request header, this header of HTTP/1.1,
If-Match applies only to allows the Request-URI, and not client to the Destination
of a COPY
advertise compliance with named features. Clients need not advertise
1, 2 or MOVE.

If bis because a COPY or MOVE is not performed due WebDAV server currently doesn't need that
information to decide how to respond to requests defined in this
specification or in HTTP/1.1. However, future extensions may define
client compliance codes. When used as a request header, the value of the Overwrite
header, the method MUST fail with a 412 (Precondition Failed) status
code.

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All DAV compliant resources MUST support the Overwrite header.

9.8 Timeout Request DAV
header MAY affect caching so this header SHOULD NOT be used on all
GET requests.

9.2 Depth Header

TimeOut

Depth = "Timeout" "Depth" ":" 1#TimeType
TimeType = ("Second-" DAVTimeOutVal ("0" | "Infinite")
DAVTimeOutVal = 1*digit

Clients may include Timeout "1" | "infinity")

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The Depth request headers in their LOCK requests.
However, header is used with methods executed on resources
which could potentially have internal members to indicate whether the server
method is not required to honor be applied only to the resource ("Depth: 0"), to the
resource and its immediate children, ("Depth: 1"), or even consider these
requests. Clients MUST NOT submit a Timeout request the resource
and all its progeny ("Depth: infinity").

The Depth header with any
method other than a LOCK method.

Timeout response values MUST use is only supported if a Second value or Infinite. method's definition
explicitly provides for such support.

The "Second" TimeType specifies following rules are the number of seconds default behavior for any method that will
elapse between granting of
supports the lock at Depth header. A method may override these defaults by
defining different behavior in its definition.

Methods which support the server, Depth header may choose not to support all
of the header's values and may define, on a case by case basis, the automatic
removal
behavior of the lock. The timeout value for TimeType "Second" MUST
NOT be greater than 2^32-1.

The timeout counter MUST be restarted method if a refresh LOCK request Depth header is
successful. The timeout counter SHOULD NOT be restarted at any other
time.

If the timeout expires then not present. For
example, the lock may be lost. Specifically, MOVE method only supports "Depth: infinity" and if
the server wishes to harvest the lock upon time-out, the server
SHOULD a
Depth header is not present will act as if an UNLOCK method was executed by the server a "Depth: infinity" header
had been applied.

Clients MUST NOT rely upon methods executing on the
resource using the lock token members of their
hierarchies in any particular order or on the timed-out lock, performed with
its override authority. Thus logs should be updated with execution being atomic
unless the
disposition particular method explicitly provides such guarantees.

Upon execution, a method with a Depth header will perform as much of the lock, notifications should be sent, etc., just
its assigned task as
they would be possible and then return a response specifying
what it was able to accomplish and what it failed to do.

So, for example, an UNLOCK request.

Servers are advised to pay close attention attempt to COPY a hierarchy may result in some of
the values submitted by
clients, as they will members being copied and some not.

Any headers on a method that has a defined interaction with the Depth
header MUST be indicative of applied to all resources in the type scope of activity the
client intends to perform. method
except where alternative behavior is explicitly defined. For
example, an applet running in a
browser may need If-Match header will have its value applied against every
resource in the method's scope and will cause the method to lock fail if
the header fails to match.

If a resource, but because of the instability
of the environment source or destination, within which the applet is running, scope of the applet may
be turned off without warning. As method
with a result, the applet Depth header is likely to
ask for locked in such a relatively small timeout value so that if way as to prevent the applet dies,
successful execution of the method, then the lock can be quickly harvested. However, a document management
system is likely to ask token for an extremely long timeout because its
user may be planning on going off-line.

A client MUST NOT assume that just because
resource MUST be submitted with the time-out has expired request in the lock has been lost. Likewise, a client MUST NOT assume that just
because If request header.

The Depth header only specifies the time-out has behavior of the method with
regards to internal children. If a resource does not expired, have internal
children then the lock still exists (and for
this reason, clients are strongly advised Depth header MUST be ignored.

Please note, however, that it is always an error to use ETags as well). submit a value

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10. Status Code Extensions to HTTP/1.1

The following status codes are added to those defined in HTTP/1.1
RFC2616 [8].

10.1 102 Processing

The 102 (Processing) status code is an interim response used to
inform 2005

for the client Depth header that the server has accepted the complete request,
but has is not yet completed it. This status code SHOULD only be sent
when allowed by the server has method's definition.
Thus submitting a reasonable expectation that "Depth: 1" on a COPY, even if the request resource does not
have internal members, will
take significant time to complete. As guidance, if result in a 400 (Bad Request). The
method is
taking longer than 20 seconds (a reasonable, should fail not because the resource doesn't have internal
members, but arbitrary value) to
process because of the server SHOULD return a 102 (Processing) response. The
server MUST send a final response after illegal value in the header.

9.3 Destination Header

Destination = "Destination" ":" ( absoluteURI )

The Destination request has been
completed.

Methods can potentially take header specifies the URI which identifies a long period of time to process,
especially
destination resource for methods such as COPY and MOVE, which take
two URIs as parameters. Note that support the Depth header. In such cases absoluteURI production is
defined in RFC2396 [5].

If the
client Destination value is an absolute URI, it may time-out the connection while waiting for name a response. To
prevent this different
server (or different port or scheme). If the source server may return cannot
attempt a 102 (Processing) status code copy to
indicate the remote server, it MUST fail the request with a
502 (Bad Gateway) response. Servers MAY attempt to copy the client that resource
to the remote server using PUT/PROPPATCH or another mechanism.

9.4 Force-Authentication Header

Force-Authentication = "Force-Authentication" ":" Method

The Force-Authentication request header is still processing used with the
method.

10.2 207 Multi-Status

The 207 (Multi-Status) status code provides status for multiple
independent operations (see Section 12 for more information).

10.3 422 Unprocessable Entity

The 422 (Unprocessable Entity) status code means OPTIONS
method to specify that the server
understands client wants to be challenged for
authentication credentials to the content type of resource identified by the request entity (hence Request-
URI. If present on a
415(Unsupported Media Type) status code is inappropriate), and the
syntax of the request entity is correct (thus to a 400 (Bad Request) WebDAV-compliant resource, the
server MUST respond with either 401 (Unauthorized) or 501 (Not
Implemented) status code code. The Method value is inappropriate) but was unable to process used for the contained
instructions. For example, this error condition may occur if an XML
request body contains well-formed (i.e., syntactically correct), but
semantically erroneous XML instructions.

10.4 423 Locked

The 423 (Locked) status code means client to
indicate what method it intends to use first on the source or destination resource
of a method
identified in the Request-URI.

9.5 If Header

The If request header is locked. This response SHOULD contain intended to have similar functionality to
the
'missing-lock-token' element and corresponding href If-Match header defined in section 14.24 of RFC2616 [7]. However
the error
body. If header is intended for use with any URI which represents state

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10.5 424 Failed Dependency

The 424 (Failed Dependency) status code means that the method could
not be performed on the resource because the requested action
depended on another action 2005

information, referred to as a state token, about a resource as well
as ETags. A typical example of a state token is a lock token, and that action failed. For example, if
lock tokens are the only state tokens defined in this specification.
The <DAV:no-lock> state token is a
command special token that must never
match an actual valid lock token. The purpose of this is described
in section 9.5.5.

The If header's purpose is to describe a PROPPATCH method fails then, at minimum, series of state lists. If
the rest state of the
commands will also resource to which the header is applied does not
match any of the specified state lists then the request MUST fail
with 424 (Failed Dependency).

10.6 507 Insufficient Storage

The 507 (Insufficient Storage) status code means a 412 (Precondition Failed). If one of the method could not
be performed on described state
lists matches the state of the resource because then the request may succeed.

The server is unable to store must parse the representation needed If header when it appears on any request,
evaluate all the clauses, and if the conditional evaluates to successfully complete false,
fail the request. This
condition

Note that the absoluteURI production is considered to be temporary. If defined in RFC2396 [5].

RFC2518 originally defined the request which
received this status code was If header without comma separators.
This oversight meant that the result of a user action, If header couldn't be divided up among
multiple lines according to the
request HTTP header manipulation rules.
Servers supporting "bis" MUST NOT be repeated until it is requested by a separate user
action.

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11. Use of HTTP Status Codes

11.1 301 Moved Permanently

Any WebDAV request may be redirected using this status code.

11.2 302 Found

Any WebDAV request may be redirected using this status code.

11.3 400 Bad Request

This code may be used if:

o able to accept commas in If header
values. If the Host header is missing in any request
o The protocol version is HTTP/1.0
o Any has commas between tokens or clauses, the
header is improperly formatted
o The request method line is improperly formatted

11.4 403 Forbidden

To can be used if evaluated simply by removing the server does not ever accept this method on this
kind of resource. For example, if a PUT is not accepted on a
collection.

11.5 409 Conflict commas and proceeding
with the evaluation rules.

9.5.1 No-tag-list Production

The 409 Conflict is most typically returned when No-tag-list production describes a series of state tokens and
ETags. If multiple No-tag-list productions are used then one only
needs to match the state of the resource for the method that
attempts to create a new be allowed
to continue. All untagged tokens apply to the resource must fail, because one of identified in
the
collections Request-URI.

Example - no-tag-list production

If: (<opaquelocktoken:a-write-lock-token> ["I am an ETag"]), (["I
am another ETag"])

The previous header would require that the resource depends on does not exist. However, other
types of conflicts are defined identified in specifications extending RFC2518.
Therefore, this can the
Request-URI be returned locked with the specified lock token and in response to all methods.

11.6 414 Request-URI Too Long

This status code is used in HTTP 1.1 only for Request-URIs, because
full URIs arenȡt used in other headers. WebDAV specifies full URLs
in other headers, therefore this error may be used if the URI is too
long state
identified by the "I am an ETag" ETag or in other locations the state identified by
the second ETag "I am another ETag". To put the matter more plainly
one can think of the previous If header as well. This status code may be used in
response to any method being in this specification. the form (or (and
<opaquelocktoken:a-write-lock-token> ["I am an ETag"]) (and ["I am
another ETag"])).

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12. Multi-Status Response 2005

9.5.2 Tagged-list Production

The default 207 (Multi-Status) response body is a text/xml or
application/xml HTTP entity that contains a single XML element called
multistatus, which contains a set tagged-list production may be used instead of XML elements called response
which contain 200, 300, 400, and 500 series status codes generated
during the method invocation. 100 series status codes SHOULD NOT be
recorded no-tag-list
production, in order to scope each token to a response XML element. The 207 status code itself MUST
NOT be considered a success response, specific resource.
That is, it is specifies that the lists following the resource
specification only completely
successful if all response elements inside contain success status
codes. apply to the specified resource. The body scope of a 207 Multi-Status response MUST contain a URL associated
with each specific status code, so that the client can tell whether the error occurred
resource production begins with the source resource, destination list production immediately
following the resource or
some other production and ends with the next resource
production, if any. All clauses must be evaluated. If the state of
the resource named in the scope tag does not match any of the request. URLs for
collections appearing associated
state lists then the request MUST fail with a 412 (Precondition
Failed). The tagged-list production MUST NOT be used together with
the no-tag-list production, either in the results SHOULD end same If header or in a '/' character.

When a Multi-Status body is returned
continuation.

The same URI MUST NOT appear more than once in response to a PROPFIND or
another request with a single scope, all URLs appearing resource production
in an If header.

Example - Tagged List If header

In this example http://www.example.com/resource1 is being copied to
http://www.example.com/resource2. When the body method is first applied
to http://www.example.com/resource1, resource1 must be equal to or inside the request-URI, thus in the URLs MAY state
specified by "(<locktoken:a-write-lock-token> [W/"A weak ETag"])
(["strong ETag"])", that is, it either must be
absolute locked with a lock
token of "locktoken:a-write-lock-token" and have a weak entity tag
W/"A weak ETag" or MAY be relative.

o If the URLs are absolute, then the server MUST ensure that the
URLs it must have a strong entity tag "strong ETag".

That is the same prefix (scheme, host, port, and path) as the
URL of only success condition since the requested resource (which may be
http://www.bar.bar/random never has the same as method applied to it (the
only other resource listed in the
Request-URI or may be the corrected If header) and
http://www.example.com/resource2 is not listed in the response Location
header).
o If the URLs are relative, they MUST be resolved against the
Location header, if present, header.

9.5.3 Not Production

Every state token or as second choice against ETag is either current, and hence describes the
Request-URI.

When
state of a Multi-Status body is returned in response to MOVE resource, or COPY,
relative URIs resolution is ambiguous (the request had both a source not current, and a destination URL). Thus, URLs appearing in does not describe the responses to
MOVE or COPY SHOULD be absolute and fully-qualified URLs.

12.1 Responses requiring Location in Multi-Status
state of a resource. The 300-303, 305 and 307 responses defined in HTTP 1.1 normally take boolean operation of matching a Location header state token
or ETag to indicate where the client should make the
request. The Multi-Status response syntax as defined in RFC2518 did
not allow for the Location header information to be included in an
unambiguous way, so servers MAY choose not current state of a resource thus resolves to use these status codes
in Multi-Status responses. If a clients receives this status code in
Multi-Status, the client MAY reissue the request true or
false value. The "Not" production is used to the individual
resource, so reverse that value.
The scope of the server can issue a response with a Location
header for each resource. not production is the state-token or entity-tag

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Additionally, this specification defines 2005

immediately following it.

If: (Not <locktoken:write1> <locktoken:write2>)

When submitted with a new element request, this If header requires that servers
MAY use in the response element to provide a location value in
Multi-Status (see Section 13.29).

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13. XML Element Definitions

In this section, the final line of each section gives the element
type declaration using the format defined in XML [11]. all
operand resources must not be locked with locktoken:write1 and must
be locked with locktoken:write2.

The "Value"
field, where present, specifies further restrictions on Not production is particularly useful with the allowable
contents of "<DAV:no-lock>"
state token. The clause "Not <DAV:no-lock>" must evaluate to true.
Thus, any "OR" statement containing the XML element using BNF (i.e., clause "Not <DAV:no-lock>"
must also evaluate to further restrict true.

9.5.4 Matching Function

When performing If header processing, the
values definition of a PCDATA element). matching
state token or entity tag is as follows.

Identifying a resource: The "Extensibility" field discusses how resource is identified by the element may be extended URI along
with the token, in tagged list production, or by the future (or Request-URI in existing extensions
to WebDAV.

All of
untagged list production.

Matching entity tag: Where the elements defined here may be extended by entity tag matches an entity tag
associated with the addition of
attributes and child elements not defined identified resource.

Matching state token: Where there is an exact match between the state
token in this specification.

13.1 activelock XML Element

Name: activelock
Namespace: DAV:
Purpose: Describes a lock the If header and any state token on a the identified
resource.
Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT activelock (lockscope, locktype, depth, owner?, timeout?,
locktoken?, lockroot)>

13.2 depth XML Element

Name: depth
Namespace: DAV:
Purpose: The value A lock state token is considered to match if the resource
is anywhere in the scope of the Depth header.
Value: "0" | "1" | "infinity"
Extensibility: MAY be extended lock.

Example - Matching lock tokens with attributes which SHOULD be
ignored.

<!ELEMENT depth (#PCDATA) >

13.3 locktoken XML Element

Name: locktoken
Namespace: DAV:
Purpose: The collection locks

DELETE /specs/rfc2518.txt HTTP/1.1
Host: www.example.com
If: <http://www.example.com/specs/> (<locktoken:a-write-lock-token>)

For this example, the lock token associated with must be compared to the identified
resource, which is the 'specs' collection identified by the URL in
the tagged list production. If the 'specs' collection is not locked
or has a lock.
Description: The href contains lock with a single different token, the request MUST fail. If the
'specs' collection is locked (depth infinity) with that lock token URI which refers token,
then this request could succeed, both because the If header evaluates
to true, and because the lock (i.e., token for the OpaqueLockToken-URI production in section
6.4).
Extensibility: MAY be extended lock affecting the
affected resource has been provided. Alternatively, a request where
the 'rfc2518.txt' URL is associated with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT locktoken (href) > the lock token in the If
header could also succeed.

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13.4 lockroot XML Element

Name: lockroot
Namespace: DAV:
Purpose: Contains the root URL of 2005

9.5.5 If Header and Non-DAV Aware Proxies

Non-DAV aware proxies will not honor the lock, which is If header, since they will
not understand the URL through
which If header, and HTTP requires non-understood
headers to be ignored. When communicating with HTTP/1.1 proxies, the resource was addressed in
"Cache-Control: no-cache" request header MUST be used so as to
prevent the LOCK request.
Description: The href contains a URL with proxy from improperly trying to service the address of request from
its cache. When dealing with HTTP/1.0 proxies the root of "Pragma: no-
cache" request header MUST be used for the lock. same reason.

9.6 Lock-Token Header

Lock-Token = "Lock-Token" ":" Coded-URL

The server SHOULD include this in all lockdiscovery
property values and Lock-Token request header is used with the response UNLOCK method to
identify the lock to LOCK requests.
Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT lockroot (href) >

13.5 timeout XML Element

Name: timeout
Namespace: DAV:
Purpose: removed. The number of seconds remaining before a lock expires.
Value: TimeType (defined token in Section 9.8).
Extensibility: MAY be extended with attributes which SHOULD be
ignored.

<!ELEMENT timeout (#PCDATA) >

13.6 collection XML Element

Name: collection
Namespace: DAV:
Purpose: Identifies the associated Lock-Token
request header MUST identify a lock that contains the resource
identified by Request-URI as a collection. member.

The
resourcetype property of a collection resource MUST contain this
element. It Lock-Token response header is normally empty but extensions may add
sub-elements.
Extensibility: MAY be extended used with child elements or attributes
which SHOULD be ignored if not recognized.

<!ELEMENT collection EMPTY >

13.7 href XML Element

Name: href
Namespace: DAV:
Purpose: Identifies the content of LOCK method to
indicate the element lock token created as a URI. In many
situations, this URI MUST be a HTTP URI, and furthermore, it MUST
identify result of a WebDAV resource. There is one exception successful LOCK
request to this
general rule in create a new lock.

9.7 Overwrite Header

Overwrite = "Overwrite" ":" ("T" | "F")

The Overwrite request header specifies whether the lockdiscovery property, where server should
overwrite the lock token
(which state of a non-null destination resource during a COPY
or MOVE. A value of "F" states that the server must not perform the
COPY or MOVE operation if the state of the destination resource is
non-null. If the overwrite header is not included in a URI but may COPY or MOVE
request then the resource MUST treat the request as if it has an
overwrite header of value "T". While the Overwrite header appears to
duplicate the functionality of the If-Match: * header of HTTP/1.1,
If-Match applies only to the Request-URI, and not be to the Destination
of a HTTP URI) COPY or MOVE.

If a COPY or MOVE is inside not performed due to the href
element. Other specifications SHOULD be explicit if value of the href Overwrite
header, the method MUST fail with a 412 (Precondition Failed) status
code.

All DAV compliant resources MUST support the Overwrite header.

9.8 Timeout Request Header

TimeOut = "Timeout" ":" 1#TimeType
TimeType = ("Second-" DAVTimeOutVal | "Infinite")

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element 2005

DAVTimeOutVal = 1*digit

Clients may include Timeout request headers in their LOCK requests.
However, the server is not required to contain non-HTTP URIs.
Value: URI (See section 3.2.1 of RFC2616 [8])
Extensibility: MAY be extended with attributes which SHOULD be
ignored.

<!ELEMENT href (#PCDATA)>

13.8 lockentry XML Element

Name: lockentry
Namespace: DAV:
Purpose: Defines honor or even consider these
requests. Clients MUST NOT submit a Timeout request header with any
method other than a LOCK method.

Timeout response values MUST use a Second value or Infinite.

The "Second" TimeType specifies the types number of locks seconds that can be used with will
elapse between granting of the
resource.
Extensibility: MAY lock at the server, and the automatic
removal of the lock. The timeout value for TimeType "Second" MUST
NOT be extended with additional child elements or
attributes which SHOULD greater than 2^32-1.

The timeout counter MUST be ignored restarted if not recognized.

<!ELEMENT lockentry (lockscope, locktype) >

13.9 lockinfo XML Element

Name: lockinfo
Namespace: DAV:
Purpose: The lockinfo XML element is used with a refresh LOCK method to
specify request is
successful. The timeout counter SHOULD NOT be restarted at any other
time.

If the timeout expires then the type of lock may be lost. Specifically, if
the client server wishes to have created.
Extensibility: MAY be extended with additional child elements or
attributes which harvest the lock upon time-out, the server
SHOULD be ignored act as if not recognized.

<!ELEMENT lockinfo (lockscope, locktype, owner?) >

13.10 lockscope XML Element

Name: lockscope
Namespace: DAV:
Purpose: Specifies whether a lock is an exclusive UNLOCK method was executed by the server on the
resource using the lock token of the timed-out lock, or a shared
lock.
Extensibility: SHOULD NOT be extended performed with child elements. MAY
its override authority. Thus logs should be
extended updated with attributes which SHOULD the
disposition of the lock, notifications should be ignored.

<!ELEMENT lockscope (exclusive | shared) >

13.11 exclusive XML Element

Name: exclusive
Namespace: DAV:
Purpose: Specifies an exclusive lock

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Extensibility: Normally empty, but MAY be extended with additional
child elements or attributes which SHOULD be ignored if not
recognized.

<!ELEMENT exclusive EMPTY >

13.12 shared XML Element

Name: shared
Namespace: DAV:
Purpose: Specifies a shared lock
Extensibility: Normally empty, but MAY sent, etc., just as
they would be extended with additional
child elements or attributes which SHOULD for an UNLOCK request.

Servers are advised to pay close attention to the values submitted by
clients, as they will be ignored if not
recognized.

<!ELEMENT shared EMPTY >

13.13 locktype XML Element

Name: locktype
Namespace: DAV:
Purpose: Specifies indicative of the access type of activity the
client intends to perform. For example, an applet running in a lock. At present, this
specification only defines one
browser may need to lock type, the write lock.
Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT locktype (write) >

13.14 write XML Element

Name: write
Namespace: DAV:
Purpose: Specifies a write lock.
Extensibility: Normally empty, resource, but MAY be extended with additional
child elements or attributes because of the instability
of the environment within which SHOULD the applet is running, the applet may
be ignored if not
recognized.

<!ELEMENT write EMPTY >

13.15 multistatus XML Element

Name: multistatus
Namespace: DAV:
Purpose: Contains multiple response messages.
Description The responsedescription at turned off without warning. As a result, the top level applet is used likely to
provide
ask for a general message describing relatively small timeout value so that if the overarching nature of applet dies,
the
response. If this value lock can be quickly harvested. However, a document management
system is available likely to ask for an application extremely long timeout because its
user may use it
instead of presenting be planning on going off-line.

A client MUST NOT assume that just because the individual response descriptions time-out has expired
the lock has been lost. Likewise, a client MUST NOT assume that just
because the time-out has not expired, the lock still exists (and for
this reason, clients are strongly advised to use ETags as well).

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contained within 2005

10. Status Code Extensions to HTTP/1.1

The following status codes are added to those defined in HTTP/1.1
RFC2616 [7].

10.1 102 Processing

The 102 (Processing) status code is an interim response used to
inform the responses.
Extensibility: MAY be extended with additional child elements or
attributes which client that the server has accepted the complete request,
but has not yet completed it. This status code SHOULD only be ignored if not recognized.

<!ELEMENT multistatus (response+, responsedescription?) >

13.16 response XML Element

Name: locktype
Namespace: DAV:
Purpose: Holds sent
when the server has a single response describing reasonable expectation that the effect of request will
take significant time to complete. As guidance, if a method
on resource and/or its properties.
Description: A particular href MUST NOT appear more is
taking longer than once as 20 seconds (a reasonable, but arbitrary value) to
process the
child of server SHOULD return a 102 (Processing) response. The
server MUST send a final response XML element under after the request has been
completed.

Methods can potentially take a multistatus XML element.
This requirement is necessary in order long period of time to keep processing costs process,
especially methods that support the Depth header. In such cases the
client may time-out the connection while waiting for a response to linear time. Essentially, response. To
prevent this prevents having
to search in order to group together all the responses by href.
There are, however, no requirements regarding ordering based on
href values.
Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT response (href, ((href*, status)|(propstat+)),
responsedescription? , location?) >

13.17 propstat XML Element

Name: propstat
Namespace: DAV:
Purpose: Groups together server may return a prop and 102 (Processing) status element code to
indicate to the client that the server is
associated with a particular href element.
Description: still processing the
method.

10.2 207 Multi-Status

The propstat XML element MUST contain one prop XML
element and one 207 (Multi-Status) status XML element. code provides status for multiple
independent operations (see Section 12 for more information).

10.3 422 Unprocessable Entity

The contents of 422 (Unprocessable Entity) status code means the prop XML
element MUST only list server
understands the names content type of properties to which the result
in the request entity (hence a
415(Unsupported Media Type) status element applies.
Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT propstat (prop, status, responsedescription?) >

13.18 code is inappropriate), and the
syntax of the request entity is correct (thus a 400 (Bad Request)
status XML Element

Name: code is inappropriate) but was unable to process the contained
instructions. For example, this error condition may occur if an XML
request body contains well-formed (i.e., syntactically correct), but
semantically erroneous XML instructions.

10.4 423 Locked

The 423 (Locked) status
Namespace: DAV:
Purpose: Holds code means the source or destination resource
of a single HTTP status-line method is locked. This response SHOULD contain the 'missing-
lock-token' element and corresponding href in the error body.

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Value: status-line (status-line defined in RFC2616 [8]
Extensibility: MAY be extended with attributes which SHOULD be
ignored.

<!ELEMENT 2005

10.5 424 Failed Dependency

The 424 (Failed Dependency) status (#PCDATA) >

13.19 responsedescription XML Element

Name: responsedescription
Namespace: DAV:
Purpose: Contains a message code means that can the method could
not be displayed to performed on the user
explaining resource because the nature requested action
depended on another action and that action failed. For example, if a
command in a PROPPATCH method fails then, at minimum, the rest of the response.
Description: This XML element provides information suitable to
commands will also fail with 424 (Failed Dependency).

10.6 507 Insufficient Storage

The 507 (Insufficient Storage) status code means the method could not
be
presented performed on the resource because the server is unable to store
the representation needed to successfully complete the request. This
condition is considered to a user.
Extensibility: MAY be extended with attributes temporary. If the request which SHOULD be
ignored.

<!ELEMENT responsedescription (#PCDATA) >

13.20 owner XML Element

Name: owner
Namespace: DAV:
Purpose: Provides information about
received this status code was the principal taking out result of a lock.
Description The owner XML element provides information sufficient for
either directly contacting a principal (such as a telephone number
or Email URI), or for discovering the principal (such as the URL
of a homepage) who owns a lock. This information is provided by
the client, and may only be altered by the server if the owner
value provided by user action, the client is empty.
Extensibility MAY be extended with child elements, mixed content,
text content or attributes. Structured content, for example one
or more <href> child elements containing URLs, is RECOMMENDED.

<!ELEMENT owner ANY

13.21 prop XML element

Name: prop
Namespace: DAV:
Purpose: Contains properties related to a resource.
Description The prop XML element is a generic container for
properties defined on resources. All elements inside a prop XML
element
request MUST define properties related to the resource. No other
elements may NOT be used inside of repeated until it is requested by a prop element. separate user
action.

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Extensibility MAY be extended with attributes which SHOULD be ignored
if not recognized. Any child element 2005

11. Use of HTTP Status Codes

These HTTP codes are not redefined, but this element must section serves as a
reminder that these HTTP codes may be
considered used in responses to WebDAV
methods and clients must be a property name, however these are not restricted appropriately prepared to the property names defined in this document or other standards.

<!ELEMENT prop ANY

13.22 propertyupdate XML element

Name: propertyupdate
Namespace: DAV:
Purpose: Contains a handle them.

11.1 301 Moved Permanently

Any WebDAV request to alter the properties on a resource.
Description: This XML element is a container for the information
required to modify the properties on the resource. This XML
element is multi-valued.
Extensibility: MAY may be extended with additional child elements or
attributes which SHOULD redirected using this status code.

11.2 302 Found

Any WebDAV request may be ignored if not recognized.

<!ELEMENT propertyupdate (remove | set)+ >

13.23 remove XML element

Name: remove
Namespace: DAV:
Purpose: Lists the DAV properties to redirected using this status code.

11.3 400 Bad Request

This code may be removed from a resource.
Description: Remove instructs that used if:

o the properties specified Host header is missing in prop
should any request

o The protocol version is HTTP/1.0

o Any header is improperly formatted

o The request method line is improperly formatted

11.4 403 Forbidden

To be removed. Specifying used if the removal of a property that server does not exist ever accept this method on this
kind of resource. For example, if a PUT is not an error. All the XML elements in accepted on a prop XML
element inside of
collection.

11.5 409 Conflict

The 409 Conflict is most typically returned when a remove XML element MUST be empty, as only method that
attempts to create a new resource must fail, because one of the
names
collections that resource depends on does not exist. However, other
types of properties to be removed conflicts are required.
Extensibility: MAY defined in specifications extending RFC2518.
Therefore, this can be extended with additional child elements returned in response to all methods.

11.6 412 Precondition Failed

Any request may contain a conditional header defined in HTTP (If-
Match, If-Modified-Since, etc.) or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT remove (prop) >

13.24 set XML element

Name: set
Namespace: DAV:
Purpose: Lists the DAV property values to be set for a resource.
Description: The set XML element MUST contain only a prop XML
element. The elements contained by the prop XML element inside the set XML element MUST specify "If" conditional header
defined in this specification. If the name request contains a conditional
header, and value of properties if that are set on the resource identified by Request-URI. If a
property already exists condition fails to hold, then its value this error code may
be returned. This status code is replaced. Language
tagging information appearing in the scope of the prop element (in
the "xml:lang" attribute, not typically appropriate if present) MUST be persistently stored
along with the property, and MUST be subsequently retrievable

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using PROPFIND.
Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if 2005

client did not recognized.

<!ELEMENT set (prop) >

13.25 propfind XML Element

Name: propfind
Namespace: DAV:
Purpose: Specifies the properties to be returned from include a PROPFIND
method. Four special elements are specified for use with
propfind: prop, dead-props, allprop and propname. If prop conditional header in the request.

11.7 414 Request-URI Too Long

This status code is used
inside propfind it MUST NOT contain property values.
Extensibility: MAY be extended with additional child elements or
attributes which SHOULD in HTTP 1.1 only for Request-URIs, because
full URIs arenit used in other headers. WebDAV specifies full URLs
in other headers, therefore this error may be ignored used if not recognized, as the URI is too
long in other locations as
it still contains one of the required elements.

<!ELEMENT propfind (prop | dead-props | propname | allprop) >

13.26 allprop XML Element

Name: allprop
Namespace: DAV:
Purpose: The allprop XML element specifies that all names and values
of dead properties and the live properties defined by well. This status code may be used in
response to any method in this
document existing on the resource are specification.

11.8 503 Service Unavailable

This status code is particularly useful to be returned.
Extensibility: Normally empty, but MAY be extended with additional
child elements or attributes which SHOULD be ignored if not
recognized.

<!ELEMENT allprop EMPTY >

13.27 propname XML Element

Name: propname
Namespace: DAV:
Purpose: The propname XML element specifies respond to requests that only a list of
property names on
the resource is to be returned.
Extensibility: Normally empty, but MAY be extended with additional
child elements server considers a denial-of-service attack, such as excessively
large PROPFIND depth infinity requests or attributes which SHOULD be ignored if not
recognized.

<!ELEMENT propname EMPTY >

13.28 dead-props XML Element requests in quick
succession.

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Name: dead-props
Namespace: DAV:
Purpose: 2005

12. Multi-Status Response

The dead-props default 207 (Multi-Status) response body is a text/xml or
application/xml HTTP entity that contains a single XML element specifies that all dead
properties, names called
multistatus, which contains a set of XML elements called response
which contain 200, 300, 400, and values, should be returned in 500 series status codes generated
during the response.
Extensibility: Normally empty, but MAY method invocation. 100 series status codes SHOULD NOT be extended with additional
child elements or attributes which SHOULD be ignored if not
recognized.

<!ELEMENT dead-props EMPTY >

13.29 location
recorded in a response XML Element

Name: location
Namespace: DAV:
Purpose: In normal responses (not Multi-Status), some element. The 207 status codes
go along with code itself MUST
NOT be considered a Location header. When these success response, it is only completely
successful if all response elements inside contain success status codes are used
in
codes.

The body of a 207 Multi-Status response, this element is used instead.
Description: Contains response MUST contain a single href element URL associated
with the same URI each specific status code, so that
would be used in a Location header.
Extensibility: MAY be extended the client can tell whether
the error occurred with additional child elements the source resource, destination resource or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT location (href) >

13.30 error XML Element

Name: error
Namespace: DAV:
Purpose: Error responses, particularly 403 Forbidden and 409
Conflict, sometimes need more information to indicate what went
wrong. When an error response contains a body
some other resource in WebDAV, the body
is scope of the request. URLs for
collections appearing in XML with the root element 'error'. The 'error' tag results SHOULD
include end in a standard error tag defined '/' character.

When a Multi-Status body is returned in this specification response to a PROPFIND or
another specification. The 'error' tag MAY include custom error
tags (in custom namespaces) which a client can safely ignore.
Description: Contains any XML element
Extensibility: Fully extensible request with additional child elements a single scope, all URLs appearing in the body
must be equal to or
attributes which SHOULD inside the request-URI, thus the URLs MAY be ignored if not recognized.

<!ELEMENT error ANY >

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14. DAV Properties

For DAV properties,
absolute or MAY be relative.

o If the name of URLs are absolute, then the property is also server MUST ensure that the
URLs have the same prefix (scheme, host, port, and path) as the
name
URL of the XML element that contains its value. In the section
below, requested resource (which may be the final line of each section gives same as the element type
declaration using
Request-URI or may be the format defined corrected in XML [11]. The "Value" field,
where present, specifies further restrictions on the allowable
contents of response Location
header).

o If the XML element using BNF (i.e., to further restrict URLs are relative, they MUST be resolved against the
values of a PCDATA element). Note that
Location header, if present, or as second choice against the
Request-URI.

When a resource may have only one
value for Multi-Status body is returned in response to MOVE or COPY,
relative URIs resolution is ambiguous (the request had both a property of source
and a given name, so the property may only show
up once destination URL). Thus, URLs appearing in PROPFIND the responses to
MOVE or PROPPATCH requests.

Some property values are calculated by the server COPY SHOULD be absolute and it is not
appropriate fully-qualified URLs.

12.1 Responses requiring Location in Multi-Status

The 300-303, 305 and 307 responses defined in HTTP 1.1 normally take
a Location header to allow indicate where the client changes, thus they are protected.
Existing server implementations already have different sets of
RFC2518 properties protected, but clients can have some expectations
which properties are normally protected. should make the
request. The value of a protected
property may Multi-Status response syntax as defined in RFC2518 did
not be changed even by a user with permission allow for the Location header information to edit
other properties. The value of an unprotected property may be
changed by some users with appropriate permissions.

14.1 creationdate Property

Name: creationdate
Namespace: DAV:
Purpose: Records the time and date the resource was created.
Value: date-time (defined in RFC3339 [9], see the ABNF included in section
5.6.)
Protected: MAY be protected. Some an
unambiguous way, so servers allow creationdate to be
changed MAY choose not to reflect use these status codes
in Multi-Status responses. If a clients receives this status code in
Multi-Status, the time client MAY reissue the document was created if that is
more meaningful request to the user (rather than individual
resource, so that the time it was
uploaded). Thus, clients SHOULD NOT use this property in
synchronization logic (use getetag instead).
COPY/MOVE behaviour: This property value SHOULD be kept during a
MOVE operation, but is normally re-initialized when server can issue a resource is
created response with a COPY. It should not be set in a COPY.
Description: The creationdate property should be defined on all DAV
compliant resources. If present, it contains a timestamp of the
moment when the resource was created (i.e., the moment it had
non-null state).
Extensibility: MAY contain attributes which SHOULD be ignored if not
recognized.

<!ELEMENT creationdate (#PCDATA) >

14.2 displayname Property Location

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Name: displayname
Namespace: DAV:
Purpose: Provides a name 2005

header for the resource each resource.

Additionally, this specification defines a new element that is suitable for
presentation servers
MAY use in the response element to provide a user.
Value: Any text
Protected: Possibly
COPY/MOVE behaviour: This property location value SHOULD be preserved in
local COPY and MOVE operations. It MAY be attempted to be set Multi-
Status (see Section 13.29).

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13. XML Element Definitions

In this section, the final line of each section gives the element
type declaration using the format defined in
a COPY operation XML [11]. The "Value"
field, where present, specifies further restrictions on the allowable
contents of the XML element using BNF (i.e., to further restrict the
values of a remote server.
Description: PCDATA element). The displayname property should "Extensibility" field discusses how
the element may be defined on all DAV
compliant resources. If present, extended in the property contains a
description future (or in existing extensions
to WebDAV.

All of the resource that is suitable for presentation to elements defined here may be extended by the addition of
attributes and child elements not defined in this specification.

13.1 activelock XML Element

Name: activelock

Namespace: DAV:

Purpose: Describes a
user. lock on a resource.

Extensibility: MAY contain be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT displayname (#PCDATA) >

14.3 getcontentlanguage Property activelock (lockscope, locktype, depth, owner?, timeout?,
locktoken?, lockroot)>

13.2 depth XML Element

Name: getcontentlanguage depth

Namespace: DAV:

Purpose: Contains The value of the Content-Language header returned by a GET
without accept headers Depth header.

Value: language-tag (language-tag is defined in section 14.13 of
RFC2616 [8])
Protected: SHOULD NOT be protected, so that clients can reset the
language.
COPY/MOVE behaviour: This property value SHOULD be preserved in
local COPY and MOVE operations. It SHOULD be attempted to be set
in a COPY operation to a remote server.
Description: The getcontentlanguage property MUST be defined on any
DAV compliant resource that returns the Content-Language header on
a GET. "0" | "1" | "infinity"

Extensibility: MAY contain be extended with attributes which SHOULD be ignored if not
recognized.
ignored.

<!ELEMENT getcontentlanguage depth (#PCDATA) >

14.4 getcontentlength Property

Name: getcontentlength
Namespace: DAV:
Purpose: Contains the Content-Length header returned by a GET
without accept headers.

13.3 locktoken XML Element

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Value: content-length (see section 14.14 of RFC2616 [8])
Protected: SHOULD be protected so clients cannot set to misleading
values 2005

Name: locktoken

Namespace: DAV:

Purpose: The lock token associated with a lock.

Description: The getcontentlength property MUST be defined on any
DAV compliant resource that returns the Content-Length header in
response to href contains a GET.
COPY/MOVE behaviour: This property value is dependent on the size of
the destination resource, not the value of single lock token URI which refers
to the property on lock (i.e., the
source resource. OpaqueLockToken-URI production in section
6.4).

Extensibility: MAY contain be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT getcontentlength (#PCDATA) locktoken (href) >

14.5 getcontenttype Property

13.4 lockroot XML Element

Name: getcontenttype lockroot

Namespace: DAV:

Purpose: Contains the Content-Type header returned by a GET without
accept headers.
Value: media-type (defined in section 3.7 root URL of RFC2616 [8])
Protected: SHOULD NOT be protected, so clients may fix this value
COPY/MOVE behaviour: This property value SHOULD be preserved in
local COPY and MOVE operations. In a remote COPY operation that the lock, which is implemented the URL through a PUT request,
which the PUT request must have resource was addressed in the appropriate Content-Type header. LOCK request.

Description: This getcontenttype property MUST be defined on any DAV
compliant resource that returns The href contains a URL with the Content-Type header address of the root of
the lock. The server SHOULD include this in all lockdiscovery
property values and the response to a GET. LOCK requests.

Extensibility: MAY contain be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT getcontenttype (#PCDATA) lockroot (href) >

14.6 getetag Property

13.5 timeout XML Element

Name: getetag timeout

Namespace: DAV:

Purpose: Contains the ETag header returned by The number of seconds remaining before a GET without accept
headers. lock expires.

Value: entity-tag TimeType (defined in section 3.11 of RFC2616 [8])
Protected: MUST Section 9.8).

Extensibility: MAY be protected because this value is created and
controlled by the server.
COPY/MOVE behaviour: This property value is dependent on the final
state of the destination resource, not the value of the property
on the source resource. extended with attributes which SHOULD be
ignored.

<!ELEMENT timeout (#PCDATA) >

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Description: The getetag property MUST be defined on any DAV
compliant resource that returns 2005

13.6 collection XML Element

Name: collection

Namespace: DAV:

Purpose: Identifies the Etag header. Refer to RFC2616
for associated resource as a complete definition of the semantics collection. The
resourcetype property of an ETag. Note that
changes in properties or lock state MUST not cause a resourceȡs
ETag to change. collection resource MUST contain this
element. It is normally empty but extensions may add sub-
elements.

Extensibility: MAY contain attributes which be extended with child elements or attributes
which SHOULD be ignored if not recognized.

<!ELEMENT getetag (#PCDATA) collection EMPTY >

14.7 getlastmodified Property

13.7 href XML Element

Name: getlastmodified href

Namespace: DAV:

Purpose: Contains the Last-Modified header returned by a GET method
without accept headers.
Value: HTTP-date (defined in section 3.3.1 of RFC2616 [8])
Protected: SHOULD be protected because some clients may rely on the
value for appropriate caching behavior, or on the value of the
Last-Modified header to which this property is linked.
COPY/MOVE behaviour: This property value is dependent on the last
modified date of the destination resource, not Identifies the value content of the
property on the source resource. Note that some server
implementations use the file system date modified value for the
'getlastmodified' value, and element as a URI. In many
situations, this is preserved in URI MUST be a MOVE even when
the HTTP Last-Modified value SHOULD change. Thus, clients cannot
rely on this value for caching URI, and SHOULD use ETags.
Description: Note that the last-modified date on furthermore, it MUST
identify a resource SHOULD
only reflect changes in the body (the GET responses) of the WebDAV resource. A change in a property only SHOULD NOT cause the
last-modified date There is one exception to change, because clients MAY rely on this
general rule in the
last-modified date to know when to overwrite lockdiscovery property, where the existing body.
The getlastmodified property MUST lock token
(which is a URI but may not be defined on any DAV compliant
resource that returns the Last- Modified header in response to a
GET.
Extensibility: MAY contain attributes which HTTP URI) is inside the href
element. Other specifications SHOULD be ignored explicit if not
recognized. the href
element is to contain non-HTTP URIs.

Value: URI (See section 3.2.1 of RFC2616 [7])

Extensibility: MAY be extended with attributes which SHOULD be
ignored.

<!ELEMENT getlastmodified (#PCDATA) >

14.8 lockdiscovery Property href (#PCDATA)>

13.8 lockentry XML Element

Name: lockdiscovery lockentry

Namespace: DAV:
Purpose: Describes the active locks on a resource

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Protected: MUST be protected. Clients change the list of locks
through LOCK and UNLOCK, not through PROPPATCH.
COPY/MOVE behaviour: The value of this property depends on 2005

Purpose: Defines the lock
state types of the destination, not on the locks of that can be used with the source
resource.
Recall that locks are

Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if not moved in a MOVE operation.
Description: recognized.

<!ELEMENT lockentry (lockscope, locktype) >

13.9 lockinfo XML Element

Name: lockinfo

Namespace: DAV:

Purpose: The lockdiscovery property returns a listing of who has lockinfo XML element is used with a lock, what type of lock he has, LOCK method to
specify the timeout type and the time
remaining on the timeout, and the associated lock token. If there
are no locks, but the server supports locks, the property will be
present but contain zero Ƚactivelockȡ elements. If there is one
or more lock, an Ƚactivelockȡ element appears for each of lock on the resource. client wishes to have created.

Extensibility: MAY be extended with additional child elements or
attributes which SHOULD be ignored if not recognized.

<!ELEMENT lockdiscovery (activelock)* lockinfo (lockscope, locktype, owner?) >