XEP-xxxx: File Transfer Metadata

WARNING: This document has not yet been accepted for consideration or approved in any official manner by the XMPP Standards Foundation, and this document is not yet an XMPP Extension Protocol (XEP). If this document is accepted as a XEP by the XMPP Council, it will be published at <http://xmpp.org/extensions/> and announced on the <standards@xmpp.org> mailing list.

Table of Contents

1. Introduction

The current methods for file transfers include basic metadata about the file being offered such as its name, size, and date. There currently is no way to provide arbitrary details about the file being transferred. XEP-0264 starts to address this problem, but only includes thumbnails of transfers.

The design of this extension to file transfer offers is influenced by adding data forms to disco#info replies (as per Entity Capabilities [1]) and by the design of File Transfer Thumbnails [2]

2. Requirements

This document defines a way to include arbitrary data in a file transfer.

3. Use Case

The arbitrary data added to the offer is incluced in Data Forms [3] which must be formatted according to Service Discovery Extensions [4] to the root <file> element. There can be as many data forms under said <file> element as long as the FORM_TYPE field is different for each form.

4. Examples

Example 1. Inclusion of photo EXIF data in an SI file transfer offer

<iq type='set' id='offer1' to='receiver@jabber.org/resource'>
  <si xmlns='http://jabber.org/protocol/si'
      id='a0'
      mime-type='image/jpeg'
      profile='http://jabber.org/protocol/si/profile/file-transfer'>
    <file xmlns='http://jabber.org/protocol/si/profile/file-transfer'
          name='thatwildparty.jpg'
          size='3240688'>
      <x xmlns='jabber:x:data' type='result'>
        <field var='FORM_TYPE' type='hidden'>
          <value>example:dataform:exifdata</value>
        </field>
        <field var='ImageWidth'>
          <value>3872</value>
        </field>
        <field var='ImageHeight'>
          <value>2592</value>
        </field>
        <field var='Make'>
          <value>NIKON CORPORATION</value>
        </field>
        <field var='Model'>
          <value>NIKON D80</value>
        </field>
      </x>
    </file>
    ...
  </si>
</iq>

Example 2. Inclusion of photo EXIF data in a Jingle file transfer offer

<iq from='romeo@montague.lit/orchard'
    id='nzu25s8'
    to='juliet@capulet.lit/balcony'
    type='set'>
  <jingle xmlns='urn:xmpp:jingle:1'
          action='session-initiate'
          initiator='romeo@montague.lit/orchard'
          sid='851ba2'>
    <content creator='initiator' name='a-file-offer'>
      <description xmlns='urn:xmpp:jingle:apps:file-transfer:3'>
        <offer>
          <file>
            <date>1969-07-21T02:56:15Z</date>
            <desc>The wild party you should've been at</desc>
            <name>thatwildparty.jpg</name>
            <range/>
            <size>8492843</size>
            <hashes xmlns='urn:xmpp:hashes:0'>
              <hash algo='sha1'>552da749930852c69ae5d2141d3766b1</hash>
            </hashes>
            <x xmlns='jabber:x:data' type='result'>
              <field var='FORM_TYPE' type='hidden'>
                <value>example:dataform:exifdata</value>
              </field>
              <field var='ImageWidth'>
                <value>3872</value>
              </field>
              <field var='ImageHeight'>
                <value>2592</value>
              </field>
              <field var='Make'>
                <value>NIKON CORPORATION</value>
              </field>
              <field var='Model'>
                <value>NIKON D80</value>
              </field>
            </x>
          </file>
        </offer>
      </description>
      ...
    </content>
  </jingle>
</iq>

5. Security Considerations

This document introduces no security concerns above and beyond those specified in Data Forms [5].

6. IANA Considerations

This document requires no interaction with the Internet Assigned Numbers Authority (IANA) [6].

7. XMPP Registrar Considerations

This document requires no interaction with the XMPP Registrar [7]; however, specifications following the best practices defined herein may register FORM_TYPEs and field values with the XMPP Registrar.

Appendices

Appendix A: Document Information

Series: XEP
Number: xxxx
Publisher: XMPP Standards Foundation
Status: ProtoXEP
Type: Standards Track
Version: 0.0.1
Last Updated: 2011-11-11
Approving Body: XMPP Council
Dependencies: XMPP Core, XEP-0096, XEP-0234
Supersedes: None
Superseded By: None
Short Name: NOT YET ASSIGNED
This document in other formats: XML  PDF

Appendix B: Author Information

Appendix C: Legal Notices

Appendix D: Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 3920) and XMPP IM (RFC 3921) 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

Appendix H: Revision History

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

END