xep-0048.xml

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE xep SYSTEM 'xep.dtd' [
  <!ENTITY % ents SYSTEM 'xep.ent'>
%ents;
]>
<?xml-stylesheet type='text/xsl' href='xep.xsl'?>
<xep>
<header>
  <title>Bookmarks</title>
  <abstract>This specification defines an XML data format for use by XMPP clients in storing bookmarks to mult-user chatrooms and web pages. The chatroom bookmarking function includes the ability to auto-join rooms on login.</abstract>
  &LEGALNOTICE;
  <number>0048</number>
  <status>Draft</status>
  <type>Standards Track</type>
  <sig>Standards</sig>
  <dependencies>
    <spec>XMPP Core</spec>
    <spec>XEP-0060</spec>
    <spec>XEP-0223</spec>
  </dependencies>
  <supersedes/>
  <supersededby/>
  <shortname>bookmarks</shortname>
  <schemaloc>
    <url>http://www.xmpp.org/schemas/bookmarks.xsd</url>
  </schemaloc>
  <author>
    <firstname>Rachel</firstname>
    <surname>Blackman</surname>
    <email>rcb@ceruleanstudios.com</email>
    <jid>sparks@jabber.org</jid>
  </author>
  &pgmillard;
  &stpeter;
  <revision>
    <version>1.1</version>
    <date>2007-11-07</date>
    <initials>psa</initials>
    <remark><p>For security reasons, actively discouraged use of the password element; specified use of publish-subscribe private information nodes as the preferred storage mechanism; cleaned up the text and examples.</p></remark>
  </revision>
  <revision>
    <version>1.0</version>
    <date>2003-10-08</date>
    <initials>psa</initials>
    <remark><p>Per a vote of the Jabber Council, changed status to Active; also added XML schema.</p></remark>
  </revision>
  <revision>
    <version>0.3</version>
    <date>2003-05-13</date>
    <initials>rcb</initials>
    <remark><p>Re-focused to document only the existing protocol in use.</p></remark>
  </revision>
  <revision>
    <version>0.2</version>
    <date>2002-10-03</date>
    <initials>pgm</initials>
    <remark><p>Typos, etc...</p></remark>
  </revision>
  <revision>
    <version>0.1</version>
    <date>2002-10-03</date>
    <initials>pgm</initials>
    <remark><p>Initial version.</p></remark>
  </revision>
</header>

<section1 topic='Introduction' anchor='intro'>
  <p>For ease-of-use in a Jabber client, it is desirable to have a way to store shortcuts to various services and resources (such as conference rooms and web pages) as "bookmarks" that can be displayed in the user's client. Several Jabber clients have already agreed on and implemented a method to provide this service; that informal agreement is documented and expanded upon in this document. In particular, we introduce the &lt;storage/&gt; element (qualified by the 'storage:bookmarks' namespace) as a container for this sort of this data. While bookmarks data can be stored using any XML storage mechanism, this document recommends one method that is specific to XMPP.</p>
</section1>

<section1 topic='Data Format' anchor='format'>
  <p>A storage element qualified by the 'storage:bookmarks' namespace may contain a collection of child elements, each representing a bookmark to be displayed in a client.  At present, only two sub-elements are defined: &lt;conference/&gt; for bookmarking of &xep0045; rooms and &lt;url/&gt; for bookmarking of web pages.</p>
  <p>All child elements allow a 'name' attribute, which is the friendly name by which they will be displayed in the client.  If an element lacks a 'name' attribute, the client SHOULD generate an appropriate substitution based on the other available data.</p>
  <section2 topic='The conference element' anchor='format-conference'>
    <p>A common use case is bookmarking of multi-user chat rooms.  A room is bookmarked using the &lt;conference/&gt; child element. The syntax is as follows.</p>
    <table caption='Syntax of conference element'>
      <tr>
        <th>Element or Attribute</th>
        <th>Definition</th>
        <th>Datatype</th>
        <th>Inclusion</th>
      </tr>
      <tr>
        <td>'autojoin' attribute</td>
        <td>Whether the client should automatically join the conference room on login.</td>
        <td>boolean defaulting to false &BOOLEANNOTE;</td>
        <td>OPTIONAL</td>
      </tr>
      <tr>
        <td>'jid' attribute</td>
        <td>The JabberID of the chat room.</td>
        <td>string</td>
        <td>REQUIRED</td>
      </tr>
      <tr>
        <td>'name' attribute</td>
        <td>A friendly name for the bookmark.</td>
        <td>string</td>
        <td>RECOMMENDED</td>
      </tr>
      <tr>
        <td>&lt;nick/&gt; element</td>
        <td>The user's preferred roomnick for the chatroom.</td>
        <td>string</td>
        <td>OPTIONAL</td>
      </tr>
      <tr>
        <td>&lt;password/&gt; element</td>
        <td>Unencrypted string for the password needed to enter a password-protected room. For security reasons, use of this element is NOT RECOMMENDED.</td>
        <td>string</td>
        <td>NOT RECOMMENDED</td>
      </tr>
    </table>
    <p>Note: The datatypes are as defined in &w3xmlschema2;.</p>
    <example caption='An example of the conference element'><![CDATA[
    <storage xmlns='storage:bookmarks'>
      <conference name='Council of Oberon'
                  autojoin='true'
                  jid='council@conference.underhill.org'>
        <nick>Puck</nick>
      </conference>
    </storage>
]]></example>
   <p>This bookmark would be displayed as 'Council of Oberon' and, if activated, would attempt to join the conference room 'council@conference.underhill.org' with nickname 'Puck'.</p>
   <p>Note: A bookmark set may contain any number of conference rooms.</p>
  </section2>
  <section2 topic='The url element' anchor='format-url'>
    <p>The &lt;url/&gt; element is designed for bookmarking web pages, i.e., HTTP or HTTPS URLs. The syntax is as follows.</p>
    <table caption='Syntax of url element'>
      <tr>
        <th>Attribute</th>
        <th>Definition</th>
        <th>Datatype</th>
        <th>Inclusion</th>
      </tr>
      <tr>
        <td>'name' attribute</td>
        <td>A friendly name for the bookmark.</td>
        <td>string</td>
        <td>RECOMMENDED</td>
      </tr>
      <tr>
        <td>'url' attribute</td>
        <td>The HTTP or HTTPS URL of the web page.</td>
        <td>anyURI</td>
        <td>REQUIRED</td>
      </tr>
    </table>
    <p>When the user chooses a URL bookmark, the client should launch an appropriate browser or load the URL directly in the client (if the client is a web-client or includes web browsing functionality).</p>
    <example caption='An example of the url element'><![CDATA[
    <storage xmlns='storage:bookmarks'>
      <url name='Complete Works of Shakespeare'
           url='http://the-tech.mit.edu/Shakespeare/'/>
    </storage>
]]></example>
    <p>This bookmark would be displayed in the client as 'Complete Works of Shakespeare' and would take the user to &lt;<link url='http://the-tech.mit.edu/Shakespeare/'>http://the-tech.mit.edu/Shakespeare/</link>&gt; when selected.</p>
    <p>Note: A bookmark set can contain any number of URLs.</p>
  </section2>
</section1>

<section1 topic='Storage' anchor='storage'>
  <p>It is RECOMMENDED to use &xep0060; for data storage, specifically through the use of personal data nodes hosted at the user's virtual publish-subscribe service as described in &xep0223; and illustrated in the following sections.</p>
  <p>Note: In the past, &xep0049; was the recommended method (see the archived version of this specification at &lt;<link url='http://www.xmpp.org/extensions/attic/xep-0048-1.0.html'>http://www.xmpp.org/extensions/attic/xep-0048-1.0.html</link>&gt;). In addition, other methods could be used, such as HTTP or WebDAV.</p>
  <section2 topic='Uploading Data' anchor='storage-pubsub-upload'>
    <example caption='Client uploads data'><![CDATA[
<iq from='juliet@capulet.lit/balcony' type='set' id='pip1'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <publish node='storage:bookmarks'>
      <item id='current'>
        <storage xmlns='storage:bookmarks'>
          <conference name='The Play&apos;s the Thing'
                      autojoin='true'
                      jid='theplay@conference.shakespeare.lit'>
            <nick>JC</nick>
          </conference>
        </storage>
      </item>
    </publish>
    <publish-options>
      <x xmlns='jabber:x:data' type='submit'>
        <field var='FORM_TYPE' type='hidden'>
          <value>http://jabber.org/protocol/pubsub#publish-options</value>
        </field>
        <field var='pubsub#persist_items'>
          <value>true</value>
        </field>
        <field var='pubsub#access_model'>
          <value>whitelist</value>
        </field>
      </x>
    </publish-options>
  </pubsub>
</iq>
]]></example>
    <example caption='Server acknowledges successful storage'><![CDATA[
<iq to='juliet@capulet.lit/balcony' type='result' id='pip1'/>
]]></example>
  </section2>
  <section2 topic='Receiving Notifications' anchor='storage-pubsub-notify'>
    <p>The stored data is automatically pushed to all of the user's connected resources.</p>
    <example caption='Publisher receives event notification'><![CDATA[
<message from='juliet@capulet.lit'
         to='juliet@capulet.lit/balcony'
         type='headline'
         id='rnfoo1'>
  <event xmlns='http://jabber.org/protocol/pubsub#event'>
    <items node='storage:bookmarks'>
      <item id='current'>
        <storage xmlns='storage:bookmarks'>
          <conference name='The Play&apos;s the Thing'
                      autojoin='true'
                      jid='theplay@conference.shakespeare.lit'>
            <nick>JC</nick>
          </conference>
        </storage>
      </item>
    </items>
  </event>
</message>

<message from='juliet@capulet.lit'
         to='juliet@capulet.lit/chamber'
         type='headline'
         id='rnfoo2'>
  <event xmlns='http://jabber.org/protocol/pubsub#event'>
    <items node='storage:bookmarks'>
      <item id='current'>
        <storage xmlns='storage:bookmarks'>
          <conference name='The Play&apos;s the Thing'
                      autojoin='true'
                      jid='theplay@conference.shakespeare.lit'>
            <nick>JC</nick>
          </conference>
        </storage>
      </item>
    </items>
  </event>
</message>
]]></example>
  </section2>
  <section2 topic='Retrieving Data' anchor='storage-pubsub-retrieve'>
    <p>In order to retrieve stored data without receiving notifications (e.g., upon initial login), the user's client sends a retrieve-items request as specified in <cite>XEP-0060</cite>.</p>
    <example caption='Client requests all items'><![CDATA[
<iq from='juliet@capulet.lit/randomID' type='get' id='retrieve1'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <items node='storage:bookmarks'/>
  </pubsub>
</iq>
]]></example>
    <example caption='Server returns all items'><![CDATA[
<iq type='result'
    to='juliet@capulet.lit/randomID'
    id='retrieve1'>
  <pubsub xmlns='http://jabber.org/protocol/pubsub'>
    <items node='storage:bookmarks'>
      <item id='current'>
        <storage xmlns='storage:bookmarks'>
          <conference name='The Play&apos;s the Thing'
                      autojoin='true'
                      jid='theplay@conference.shakespeare.lit'>
            <nick>JC</nick>
          </conference>
        </storage>
      </item>
    </items>
  </pubsub>
</iq>
]]></example>
  </section2>
</section1>

<section1 topic='Security Considerations' anchor='security'>
  <p>Security considerations related to object persistent via publish-subscribe are described in XEP-0060 and <cite>XEP-0223</cite>.</p>
  <p>Use of the &lt;password/&gt; child of the &lt;conference/&gt; element is NOT RECOMMENDED, since the password could be discovered by a third party, e.g. an eavesdropper (if channel encryption is not used) or a server administrator. However, the element MAY be used in suitably secure environments (e.g., where it is known that communications will not be sent over unencrypted channels and the server administrators are trusted). Clients SHOULD NOT default to storing passwords and MUST enable users to disable any password storage.</p>
</section1>

<section1 topic='IANA Considerations' anchor='iana'>
  <p>This document requires no interaction with &IANA;.</p>
</section1>

<section1 topic='XMPP Registrar Considerations' anchor='registrar'>
    <p>No action by the &REGISTRAR; is required, since the 'storage:bookmarks' namespace is already included in the protocol namespaces registry (see &NAMESPACES;).</p>
</section1>

<section1 topic='XML Schema' anchor='schema'>
  <code><![CDATA[
<?xml version='1.0' encoding='UTF-8'?>

<xs:schema
    xmlns:xs='http://www.w3.org/2001/XMLSchema'
    targetNamespace='storage:bookmarks'
    xmlns='storage:bookmarks'
    elementFormDefault='qualified'>

  <xs:annotation>
    <xs:documentation>
      The protocol documented by this schema is defined in
      XEP-0048: http://www.xmpp.org/extensions/xep-0048.html
    </xs:documentation>
  </xs:annotation>

  <xs:element name='storage'>
    <xs:complexType>
      <xs:choice>
        <xs:element ref='conference'/>
        <xs:element ref='url'/>
      </xs:choice>
    </xs:complexType>
  </xs:element>

  <xs:element name='conference'>
    <xs:complexType>
      <xs:sequence>
        <xs:element name='nick' type='xs:string' minOccurs='0'/>
        <xs:element name='password' type='xs:string' minOccurs='0'/>
      </xs:sequence>
      <xs:attribute name='autojoin' type='xs:boolean' use='optional' default='false'/>
      <xs:attribute name='jid' type='xs:string' use='required'/>
      <xs:attribute name='name' type='xs:string' use='required'/>
    </xs:complexType>
  </xs:element>

  <xs:element name='url'>
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base='empty'>
          <xs:attribute name='name' type='xs:string' use='required'/>
          <xs:attribute name='url' type='xs:string' use='required'/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>

  <xs:simpleType name='empty'>
    <xs:restriction base='xs:string'>
      <xs:enumeration value=''/>
    </xs:restriction>
  </xs:simpleType>

</xs:schema>
]]></code>
</section1>

<section1 topic='Author Note' anchor='authornote'>
  <p>Peter Millard, a co-author of this specification from version 0.1 through version 1.0, died on April 26, 2006.</p>
</section1>

</xep>