WEBDAV Working Group J. Reschke, Ed.
Internet-Draft S. Eissing
Expires: June 2, 2004 greenbytes
December 3, 2003
Including additional properties in WebDAV PROPFIND/allprop requests
draft-reschke-webdav-allprop-include-05
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at http://
www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
This Internet-Draft will expire on June 2, 2004.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
Recent specifications extending the Web Distributed Authoring
Protocol (WebDAV) restrict the set of properties returned
automatically upon a PROPFIND/allprop request. This specification
defines a method to add specific properties to the set of properties
returned upon PROPFIND/allprop.
Distribution of this document is unlimited. Please send comments to
the Distributed Authoring and Versioning (WebDAV) working group at
w3c-dist-auth@w3.org [1], which may be joined by sending a message
with subject "subscribe" to w3c-dist-auth-request@w3.org [2].
Discussions of the WEBDAV working group are archived at URL: http://
Reschke & Eissing Expires June 2, 2004 [Page 1]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
lists.w3.org/Archives/Public/w3c-dist-auth/.
Table of Contents
1. Notational Conventions . . . . . . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Extensions to PROPFIND/allprop . . . . . . . . . . . . . . . . 5
3.1 Example for PROPFIND/allprop/include with extended server . . 5
3.2 Example for PROPFIND/allprop/include with non-extended
server . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Changes to WebDAV DTD . . . . . . . . . . . . . . . . . . . . 9
5. Compatibility Considerations . . . . . . . . . . . . . . . . . 10
6. Internationalization Considerations . . . . . . . . . . . . . 11
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
Normative References . . . . . . . . . . . . . . . . . . . . . 13
Informative References . . . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 15
A. Alternate syntax proposal from interim WebDAV working
group meeting . . . . . . . . . . . . . . . . . . . . . . . . 16
A.1 PROPFIND/prop extension to include dead properties . . . . . . 16
A.2 Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
B. Change Log (to be removed by RFC Editor before publication) . 18
B.1 Since 'draft-reschke-webdav-allprop-include-00' . . . . . . . 18
B.2 Since 'draft-reschke-webdav-allprop-include-01' . . . . . . . 18
B.3 Since 'draft-reschke-webdav-allprop-include-02' . . . . . . . 18
B.4 Since 'draft-reschke-webdav-allprop-include-03' . . . . . . . 18
B.5 Since 'draft-reschke-webdav-allprop-include-04' . . . . . . . 18
Intellectual Property and Copyright Statements . . . . . . . . 19
Reschke & Eissing Expires June 2, 2004 [Page 2]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
1. Notational Conventions
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].
Reschke & Eissing Expires June 2, 2004 [Page 3]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
2. Introduction
Recent specifications extending the "Web Distributed Authoring
Protocol" (WebDAV, [RFC2518]) like "Versioning Extensions to WebDAV"
[RFC3253] and "WebDAV Access Control Protocol" [ACL] restrict the set
of properties returned automatically upon a PROPFIND/allprop request
in order to avoid the expensive computation of properties that the
client in many cases isn't interested in.
However, this change from the behaviour defined in WebDAV can lead to
situations where clients need to perform two requests to retrieve all
properties they are interested in (one using PROPFIND/allprop, then
PROPFIND/prop enumerating the new properties that weren't reported
upon the first request). This specification defines a
backward-compatible extension to add specific properties to the set
of properties returned upon PROPFIND/allprop, thus saving at least
one PROPFIND request.
This document defines an extension element that could ultimately
become part of the core WebDAV protocol. Being just an individual
submission, it currently defines it in the proprietary namespace
http://sapportals.com/xmlns/cm/webdav
instead of the "DAV:" namespace. It uses a prefix of "in:" for
referring to elements in this namespace. However, WebDAV server and
clients are free to use any prefix, provided that there is a
namespace declaration that binds the prefix to the URI of the same
namespace.
Reschke & Eissing Expires June 2, 2004 [Page 4]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
3. Extensions to PROPFIND/allprop
The "allprop" version of PROPFIND is extended to take an optional
in:include element. When present, it contains a set of property names
that shall be reported in addition to those properties that the
server usually would return upon PROPFIND/allprop.
3.1 Example for PROPFIND/allprop/include with extended server
>>Request
PROPFIND /container/front.html HTTP/1.1
Host: www.example.org
Depth: 1
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<propfind xmlns="DAV:"
xmlns:in="http://sapportals.com/xmlns/cm/webdav">
<allprop/>
<in:include>
<checked-in/>
<checked-out/>
</in:include>
</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.org/container/front.html</href>
<propstat>
<prop>
<R:bigbox xmlns:R="http://www.example.org/boxschema/">
<R:BoxType>Box type B</R:BoxType>
</R:bigbox>
<creationdate>1997-12-01T18:27:21-08:00</creationdate>
<displayname>Example HTML resource</displayname>
<getcontentlength>4525</getcontentlength>
<getcontenttype>text/html</getcontenttype>
<getetag>zzyzx</getetag>
<getlastmodified
Reschke & Eissing Expires June 2, 2004 [Page 5]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
>Monday, 12-Jan-98 09:25:56 GMT</getlastmodified>
<resourcetype/>
<supportedlock>
<lockentry>
<lockscope><exclusive/></lockscope>
<locktype><write/></locktype>
</lockentry>
<lockentry>
<lockscope><shared/></lockscope>
<locktype><write/></locktype>
</lockentry>
</supportedlock>
<checked-in>
<href
>http://www.example.org/vsn/container/front.html-1</href>
</checked-in>
</prop>
<status>HTTP/1.1 200 OK</status>
</propstat>
<propstat>
<prop>
<checked-out/>
</prop>
<status>HTTP/1.1 404 NOT FOUND</status>
</propstat>
</response>
</multistatus>
In this example, the server has recognized the extension element
in:include and included the properties DAV:checked-in and
DAV:checked-out (as defined in [RFC3253]).
Reschke & Eissing Expires June 2, 2004 [Page 6]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
3.2 Example for PROPFIND/allprop/include with non-extended server
>>Request
PROPFIND /container/front.html HTTP/1.1
Host: www.example.org
Depth: 1
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<propfind xmlns="DAV:"
xmlns:in="http://sapportals.com/xmlns/cm/webdav">
<allprop/>
<in:include>
<checked-in/>
<checked-out/>
</in:include>
</propfind>
Reschke & Eissing Expires June 2, 2004 [Page 7]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
>>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.org/container/front.html</href>
<propstat>
<prop>
<R:bigbox xmlns:R="http://www.example.org/boxschema/">
<R:BoxType>Box type B</R:BoxType>
</R:bigbox>
<creationdate>1997-12-01T18:27:21-08:00</creationdate>
<displayname>Example HTML resource</displayname>
<getcontentlength>4525</getcontentlength>
<getcontenttype>text/html</getcontenttype>
<getetag>zzyzx</getetag>
<getlastmodified
>Monday, 12-Jan-98 09:25:56 GMT</getlastmodified>
<resourcetype/>
<supportedlock>
<lockentry>
<lockscope><exclusive/></lockscope>
<locktype><write/></locktype>
</lockentry>
<lockentry>
<lockscope><shared/></lockscope>
<locktype><write/></locktype>
</lockentry>
</supportedlock>
</prop>
<status>HTTP/1.1 200 OK</status>
</propstat>
</response>
</multistatus>
In this case the in:include element was simply ignored. The client
can detect this situation by checking for the presence of the
requested properties and will have to issue an additional PROPFIND/
prop request (to retrieve the missing properties).
Reschke & Eissing Expires June 2, 2004 [Page 8]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
4. Changes to WebDAV DTD
<!ELEMENT propfind ((allprop, in:include+) | propname | prop) >
<!ELEMENT in:include ANY >
Note that the WebDAV DTD is informal only and cannot be used to
validate request or response bodies (due to the inability to properly
work with XML namespaces).
Reschke & Eissing Expires June 2, 2004 [Page 9]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
5. Compatibility Considerations
This specification introduces a new child element for the
DAV:propfind element, defined in Section 4. Old servers will ignore
this element (see [RFC2518], chapter 14). Clients can detect this
situation as outlined in Section 3.2.
Clients not aware of this specification will not be affected at all,
because they will never use the new in:include element in PROPFIND
requests.
Reschke & Eissing Expires June 2, 2004 [Page 10]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
6. Internationalization Considerations
This proposal builds on [RFC2518], and inherits its
internationalizability.
Reschke & Eissing Expires June 2, 2004 [Page 11]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
7. IANA Considerations
This proposal does not introduce any new IANA considerations, since
it does not specify any new namespaces (in the general sense), but
merely uses existing ones.
Reschke & Eissing Expires June 2, 2004 [Page 12]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2518] Goland, Y., Whitehead, E., Faizi, A., Carter, S. and D.
Jensen, "HTTP Extensions for Distributed Authoring --
WEBDAV", RFC 2518, February 1999.
[RFC3253] Clemm, G., Amsden, J., Ellison, T., Kaler, C. and J.
Whitehead, "Versioning Extensions to WebDAV", RFC 3253,
March 2002.
Reschke & Eissing Expires June 2, 2004 [Page 13]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
Informative References
[ACL] Clemm, G., Hopkins, A., Sedlar, E. and J. Whitehead,
"WebDAV Access Control Protocol", ID
draft-ietf-webdav-acl-12, October 2003, <http://
www.webdav.org/acl/protocol/draft-ietf-webdav-acl-12.htm>.
[ID-RFC2518bis]
Dusseault, L. and J. Crawford, "HTTP Extensions for
Distributed Authoring - WebDAV RFC2518 bis", ID
draft-ietf-webdav-rfc2518bis-05, October 2003, <http://
greenbytes.de/tech/webdav/
draft-ietf-webdav-rfc2518bis-05.txt>.
Reschke & Eissing Expires June 2, 2004 [Page 14]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
URIs
[1] <mailto:w3c-dist-auth@w3.org>
[2] <mailto:w3c-dist-auth-request@w3.org?subject=subscribe>
Authors' Addresses
Julian F. Reschke (editor)
greenbytes GmbH
Salzmannstrasse 152
Muenster, NW 48159
Germany
Phone: +49 251 2807760
Fax: +49 251 2807761
EMail: julian.reschke@greenbytes.de
URI: http://greenbytes.de/tech/webdav/
Stefan Eissing
greenbytes GmbH
Salzmannstrasse 152
Muenster, NW 48159
Germany
Phone: +49 251 2807760
Fax: +49 251 2807761
EMail: stefan.eissing@greenbytes.de
URI: http://greenbytes.de/tech/webdav/
Reschke & Eissing Expires June 2, 2004 [Page 15]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
Appendix A. Alternate syntax proposal from interim WebDAV working group
meeting
This section briefly describes an alternate approach to the problem
covered by this draft. It was discussed during the interim WebDAV
working group meeting in January 2003 and was supported by all
meeting attendees. It was also added to the latest draft for the
revision of [RFC2518], [ID-RFC2518bis].
A.1 PROPFIND/prop extension to include dead properties
Additional PROPFIND marshalling:
<!ELEMENT propfind (allprop | propname | (prop, dead-props?)) >
<!ELEMENT dead-props EMPTY >
The DAV:dead-props element can be added to PROPFIND requests that
retrieve named properties using DAV:prop. When present, the server
MUST include all dead properties defined on the resource.
A.2 Example
This example shows the alternate syntax applied to the example from
Section 3.1.
>>Request
PROPFIND /container/front.html HTTP/1.1
Host: www.example.org
Depth: 1
Content-Type: text/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<propfind xmlns="DAV:">
<prop>
<checked-in />
<checked-out />
</prop>
<dead-props />
</propfind>
Reschke & Eissing Expires June 2, 2004 [Page 16]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
>>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.org/container/front.html</href>
<propstat>
<prop>
<R:bigbox xmlns:R="http://www.example.org/boxschema/">
<R:BoxType>Box type B</R:BoxType>
</R:bigbox>
<checked-in>
<href
>http://www.example.org/vsn/container/front.html-1</href>
</checked-in>
</prop>
<status>HTTP/1.1 200 OK</status>
</propstat>
<propstat>
<prop>
<checked-out/>
</prop>
<status>HTTP/1.1 404 NOT FOUND</status>
</propstat>
</response>
</multistatus>
Reschke & Eissing Expires June 2, 2004 [Page 17]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
Appendix B. Change Log (to be removed by RFC Editor before publication)
B.1 Since 'draft-reschke-webdav-allprop-include-00'
Moved <include> element out of "DAV:" namespace.
Updated reference to deltaV (now RFC3253).
Changed examples to explicitly use utf-8 encoding for HTTP content
type and XML encoding.
Updated WebDAV ACL reference to draft 07.
Made sure figures fit in 72 columns.
Split references into "Normative" and "Informative".
B.2 Since 'draft-reschke-webdav-allprop-include-01'
Updated WebDAV ACL reference to draft 09.
B.3 Since 'draft-reschke-webdav-allprop-include-02'
Fixed XML errors in examples (wrong closing href tags).
Replaced domain names in examples according to RFC2606: "www.foo.bar"
by "www.example.org".
Shortened checked-in URI to fit into 72 characters in example.
B.4 Since 'draft-reschke-webdav-allprop-include-03'
Added short description of alternate syntax discussed during interim
WebDAV WG meeting (January 2003).
B.5 Since 'draft-reschke-webdav-allprop-include-04'
DTD fix for dead-props variant. Remove superfluous IP and copyright
sections. Added reference to RFC2518bis. Updated reference to ACL
draft.
Reschke & Eissing Expires June 2, 2004 [Page 18]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
Full Copyright Statement
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assignees.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
Reschke & Eissing Expires June 2, 2004 [Page 19]
Internet-Draft WebDAV PROPFIND/allprop/include December 2003
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgment
Funding for the RFC Editor function is currently provided by the
Internet Society.
Reschke & Eissing Expires June 2, 2004 [Page 20]