Network Working Group J. F. Reschke, Editor Internet Draft greenbytes Expires: December 2003 S. Eissing greenbytes June 2003 Including additional properties in WebDAV PROPFIND/allprop requests draft-reschke-webdav-allprop-include-04 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 in December 2003. 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. Reschke & Eissing Expires December 2003 [Page 1] Internet Draft WebDAV PROPFIND/allprop/include June 2003 Distribution of this document is unlimited. Please send comments to the Distributed Authoring and Versioning (WebDAV) working group at w3c-dist-auth@w3.org, which may be joined by sending a message with subject "subscribe" to w3c-dist-auth-request@w3.org. Discussions of the WEBDAV working group are archived at URL: http://lists.w3.org/Archives/Public/w3c-dist-auth/. Reschke & Eissing Expires December 2003 [Page 2] Internet Draft WebDAV PROPFIND/allprop/include June 2003 Table of Contents Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . 3 1 Notational Conventions . . . . . . . . . . . . . . . . . . . . 4 2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 3 Extensions to PROPFIND/allprop . . . . . . . . . . . . . . . . 6 3.1 Example for PROPFIND/allprop/include with extended server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.2 Example for PROPFIND/allprop/include with non-extended server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 Changes to WebDAV DTD . . . . . . . . . . . . . . . . . . . . . 10 5 Compatibility Considerations . . . . . . . . . . . . . . . . . 11 6 Internationalization Considerations . . . . . . . . . . . . . . 12 7 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 13 8 Copyright . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 9 Intellectual Property . . . . . . . . . . . . . . . . . . . . . 15 Normative References . . . . . . . . . . . . . . . . . . . . . . 16 Informative References . . . . . . . . . . . . . . . . . . . . . 16 Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 A Alternate syntax proposal from interim WebDAV working group meeting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 A.1 PROPFIND/prop extension to include dead properties . . . . 17 A.2 Example . . . . . . . . . . . . . . . . . . . . . . . . . . 17 B Change Log . . . . . . . . . . . . . . . . . . . . . . . . . . 19 B.1 Since 'draft-reschke-webdav-allprop-include-00' . . . . . . 19 B.2 Since 'draft-reschke-webdav-allprop-include-01' . . . . . . 19 B.3 Since 'draft-reschke-webdav-allprop-include-02' . . . . . . 19 B.4 Since 'draft-reschke-webdav-allprop-include-03' . . . . . . 19 Reschke & Eissing Expires December 2003 [Page 3] Internet Draft WebDAV PROPFIND/allprop/include June 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 December 2003 [Page 4] Internet Draft WebDAV PROPFIND/allprop/include June 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 December 2003 [Page 5] Internet Draft WebDAV PROPFIND/allprop/include June 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 >>Response HTTP/1.1 207 Multi-Status Content-Type: text/xml; charset="utf-8" Content-Length: xxxx http://www.example.org/container/front.html Box type B 1997-12-01T18:27:21-08:00 Reschke & Eissing Expires December 2003 [Page 6] Internet Draft WebDAV PROPFIND/allprop/include June 2003 Example HTML resource 4525 text/html zzyzx Monday, 12-Jan-98 09:25:56 GMT http://www.example.org/vsn/container/front.html-1 HTTP/1.1 200 OK HTTP/1.1 404 NOT FOUND 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]). 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 Reschke & Eissing Expires December 2003 [Page 7] Internet Draft WebDAV PROPFIND/allprop/include June 2003 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 http://www.example.org/container/front.html Box type B 1997-12-01T18:27:21-08:00 Example HTML resource 4525 text/html zzyzx Monday, 12-Jan-98 09:25:56 GMT Reschke & Eissing Expires December 2003 [Page 8] Internet Draft WebDAV PROPFIND/allprop/include June 2003 HTTP/1.1 200 OK 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 December 2003 [Page 9] Internet Draft WebDAV PROPFIND/allprop/include June 2003 4 Changes to WebDAV DTD 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 December 2003 [Page 10] Internet Draft WebDAV PROPFIND/allprop/include June 2003 5 Compatibility Considerations This specification introduces a new child element for the DAV:propfind element, defined in section4. Old servers will ignore this element (see [RFC2518], chapter 14). Clients can detect this situation as outlined in section3.2. 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 December 2003 [Page 11] Internet Draft WebDAV PROPFIND/allprop/include June 2003 6 Internationalization Considerations This proposal builds on [RFC2518], and inherits its internationalizability. Reschke & Eissing Expires December 2003 [Page 12] Internet Draft WebDAV PROPFIND/allprop/include June 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 December 2003 [Page 13] Internet Draft WebDAV PROPFIND/allprop/include June 2003 8 Copyright To be supplied by the RFC Editor. Reschke & Eissing Expires December 2003 [Page 14] Internet Draft WebDAV PROPFIND/allprop/include June 2003 9 Intellectual Property To be supplied by the RFC Editor. Reschke & Eissing Expires December 2003 [Page 15] Internet Draft WebDAV PROPFIND/allprop/include June 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.R. and Jensen, D., "HTTP Extensions for Distributed Authoring -- WEBDAV", RFC 2518, February 1999. [RFC3253] Clemm, G., Amsden, J., Ellison, T., Kaler, C. and Whitehead, J., "Versioning Extensions to WebDAV", RFC 3253, March 2002. Informative References [ACL] Clemm, G., Hopkins, A., Sedlar, E. and Whitehead, J., "WebDAV Access Control Protocol", ID draft-ietf-webdav- acl-09, July 2002. Author's 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 December 2003 [Page 16] Internet Draft WebDAV PROPFIND/allprop/include June 2003 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. A.1 PROPFIND/prop extension to include dead properties Additional PROPFIND marshalling: 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 section3.1. >>Request PROPFIND /container/front.html HTTP/1.1 Host: www.example.org Depth: 1 Content-Type: text/xml; charset="utf-8" Content-Length: xxxx Reschke & Eissing Expires December 2003 [Page 17] Internet Draft WebDAV PROPFIND/allprop/include June 2003 >>Response HTTP/1.1 207 Multi-Status Content-Type: text/xml; charset="utf-8" Content-Length: xxxx http://www.example.org/container/front.html Box type B http://www.example.org/vsn/container/front.html-1 HTTP/1.1 200 OK HTTP/1.1 404 NOT FOUND Reschke & Eissing Expires December 2003 [Page 18] Internet Draft WebDAV PROPFIND/allprop/include June 2003 B Change Log B.1 Since 'draft-reschke-webdav-allprop-include-00' Moved 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). 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Acknowledgement Funding for the RFC editor function is currently provided by the Internet Society. Reschke & Eissing Expires December 2003 [Page 20]