XEP-0411: Bookmarks Conversion

This specification describes a method to migrate to PEP based bookmarks without loosing compatibility with client that still use Private XML.
Daniel Gultsch
© 1999 – 2019 XMPP Standards Foundation. SEE LEGAL NOTICES.


WARNING: This Standards-Track document is Experimental. Publication as an XMPP Extension Protocol does not imply approval of this proposal by the XMPP Standards Foundation. Implementation of the protocol described herein is encouraged in exploratory implementations, but production systems are advised to carefully consider whether it is appropriate to deploy implementations of this protocol before it advances to a status of Draft.
Standards Track
0.2.0 (2018-11-08)
Document Lifecycle
  1. Experimental
  2. Proposed
  3. Draft
  4. Final

1. Introduction

Bookmark Storage (XEP-0048) [1] has a long time ago moved from Private XML Storage (XEP-0049) [2] as a storage backend to using Personal Eventing Protocol (XEP-0163) [3] instead. However lots of implementations are still using Private XML which creates a bit of a chicken and egg problem since clients who want to use the more efficient PEP method would either have to support both and synchronize them properly or render themselves incompatible with other clients. An easy way out of that conundrum is to have the server do the conversion for us.

This XEP defines a method to convert between the different storage backends of XEP-0048 and is not influenced by the existence of Bookmarks 2 (This Time it's Serious) (XEP-0402) [4]. Bookmarks 2 defines its own conversion mechanism but the adoption of Bookmarks 2 - at the time of writing this XEP - is questionable.

2. Discovery

The conversion is transparent to the publishing entity. However an entity might want to discover if a service will be performing the conversion and soley rely on PEP to access bookmarks without segregating clients that only support Private XML.

The service MUST include a Service Discovery (XEP-0030) [5] feature of "urn:xmpp:bookmarks-conversion:0" on the account.

Example 1. Client sends service discovery request to own account
<iq from='romeo@montague.tld/garden'
  <query xmlns='http://jabber.org/protocol/disco#info'/>
Example 2. Server includes feature namespace in response
<iq from='romeo@montague.tld'
  <query  xmlns='http://jabber.org/protocol/disco#info'>
    <feature var='urn:xmpp:bookmarks-conversion:0'/>

3. Conversion

Modern clients are expected to use PEP (XEP-0084) as interface to upload and retrieve their bookmarks and not explicitly request bookmarks from private XML anymore. Thus a service MUST support conversion from PEP to Private XML and vice versa. Whether PEP and Private XML are fed from the same data source or if they get copied over when ever one of them gets written is out of scope of this document.

When a legacy client modifies bookmarks over Private XML the service MUST send out notification messages to all subscribers of the 'storage:bookmarks' node.

4. Implementation Notes

For server implementations where the data is just copied over the server should make sure that the data gets copied from Private XML to PEP before the user logs in for the first time. Otherwise it won’t generate a PEP notification and clients that only rely on PEP will not be aware of any preexisting bookmarks.

5. Security Considerations

PEP nodes can have an access model other than 'whitelist'. When copying data over from Private XML Storage to PEP the service MUST make that the user is the only one who has access to that node. This can happen by either changing the access model accordingly or not doing the conversion.

6. IANA Considerations

This document requires no interaction with the Internet Assigned Numbers Authority (IANA).

7. XMPP Registrar Considerations

This specification defines the following XML namespace:

8. XML Schema


9. Acknowledgements

Special thanks to Emmanuel Gil Peyrot who created a proof of concept module for Prosody.


Appendix A: Document Information

XMPP Standards Foundation
Standards Track
Last Updated
Approving Body
XMPP Council
XMPP Core, XEP-0084, XEP-0153
Superseded By
Short Name
Source Control

This document in other formats: XML  PDF

Appendix B: Author Information

Daniel Gultsch


This XMPP Extension Protocol is copyright © 1999 – 2018 by the XMPP Standards Foundation (XSF).


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Disclaimer of Warranty

## NOTE WELL: This Specification is provided on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. ##

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IPR Conformance

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Appendix D: Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 6120) and XMPP IM (RFC 6121) specifications contributed by the XMPP Standards Foundation to the Internet Standards Process, which is managed by the Internet Engineering Task Force in accordance with RFC 2026. Any protocol defined in this document has been developed outside the Internet Standards Process and is to be understood as an extension to XMPP rather than as an evolution, development, or modification of XMPP itself.

Appendix E: Discussion Venue

The primary venue for discussion of XMPP Extension Protocols is the <standards@xmpp.org> discussion list.

Discussion on other xmpp.org discussion lists might also be appropriate; see <http://xmpp.org/about/discuss.shtml> for a complete list.

Errata can be sent to <editor@xmpp.org>.

Appendix F: Requirements Conformance

The following requirements keywords as used in this document are to be interpreted as described in RFC 2119: "MUST", "SHALL", "REQUIRED"; "MUST NOT", "SHALL NOT"; "SHOULD", "RECOMMENDED"; "SHOULD NOT", "NOT RECOMMENDED"; "MAY", "OPTIONAL".

Appendix G: Notes

1. XEP-0048: Bookmark Storage <https://xmpp.org/extensions/xep-0048.html>.

2. XEP-0049: Private XML Storage <https://xmpp.org/extensions/xep-0049.html>.

3. XEP-0163: Personal Eventing Protocol <https://xmpp.org/extensions/xep-0163.html>.

4. XEP-0402: Bookmarks 2 (This Time it's Serious) <https://xmpp.org/extensions/xep-0402.html>.

5. XEP-0030: Service Discovery <https://xmpp.org/extensions/xep-0030.html>.

Appendix H: Revision History

Note: Older versions of this specification might be available at http://xmpp.org/extensions/attic/

  1. Version 0.2.0 (2018-11-08)
    Accepted by vote of Council on 2018-10-03.
    XEP Editor (jsc)
  2. Version 0.1.0 (2018-09-18)

    First draft.