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xeps/xep-0277.xml
2011-06-15 10:15:32 -06:00

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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>Microblogging over XMPP</title>
<abstract>This specification defines a method for microblogging over XMPP.</abstract>
&LEGALNOTICE;
<number>0277</number>
<status>Experimental</status>
<type>Standards Track</type>
<sig>None</sig>
<approver>Council</approver>
<dependencies/>
<supersedes/>
<supersededby/>
<shortname>microblog</shortname>
&stpeter;
&hildjj;
<author>
<firstname>Sergey</firstname>
<surname>Dobrov</surname>
<email>binary@jrudevels.org</email>
<jid>binary@jrudevels.org</jid>
<uri>http://jrudevels.org/</uri>
</author>
<author>
<firstname>Valérian</firstname>
<surname>Saliou</surname>
<email>vanaryon@gmail.com</email>
<jid>vanaryon@jappix.com</jid>
<uri>http://vanaryon.eu/</uri>
</author>
<revision>
<version>0.5</version>
<date>2011-06-15</date>
<initials>vs</initials>
<remark><p>Changed the commenting Pubsub service from PEP to external.</p></remark>
</revision>
<revision>
<version>0.4</version>
<date>2011-06-01</date>
<initials>vs</initials>
<remark><p>Added microblog informations feature, ID innacurracy fixed, urn:xmpp:inbox support added, new commenting namespaces, first comment marker, security considerations added.</p></remark>
</revision>
<revision>
<version>0.3</version>
<date>2011-04-26</date>
<initials>vs</initials>
<remark><p>Comments link "link[rel=related]" is now "link[rel=replies]" and "title" is now "content[type=text]" or "content[type=xhtml]"; added geolocation feature; added commenting feature on attachments.</p></remark>
</revision>
<revision>
<version>0.2</version>
<date>2011-04-20</date>
<initials>vs</initials>
<remark><p>Added file attachment and commenting features; updated XML namespaces in examples.</p></remark>
</revision>
<revision>
<version>0.1</version>
<date>2010-01-27</date>
<initials>psa</initials>
<remark><p>Initial version as accepted for publication by the XMPP Council.</p></remark>
</revision>
<revision>
<version>0.0.1</version>
<date>2008-05-07</date>
<initials>psa/jh</initials>
<remark><p>First draft.</p></remark>
</revision>
</header>
<section1 topic='Introduction' anchor='intro'>
<p>Microblogging is an increasingly popular technology for lightweight interaction over the Internet. It differs from traditional blogging in that:</p>
<ul>
<li>Posts are short (typically less than 140 characters, which is the limit in SMS).</li>
<li>Posts are in plain text.</li>
<li>People can reply to your posts, but not directly comment on them.</li>
<li>People learn about your posts only if they have permission to view them.</li>
<li>Your microblogging feed is discovered based on your identity at a domain or with a service.</li>
</ul>
<p>These characteristics map well to instant messaging systems such as those built using Jabber/XMPP technologies (e.g., permissions can be based on existing presence subscriptions as reflected in the XMPP roster or "buddy list"). Furthermore, the push nature of XMPP (especially as formalized in the &xep0163; profile of &xep0060; overcomes the problems of polling for updates via HTTP, which has caused scaling issues in existing microblogging services. Therefore this specification defines a method for microblogging over XMPP, building on the existing method for transporting Atom syndication data &rfc4287; over XMPP as described in &atomsub;. These XMPP-based methods are complementary to HTTP-based methods, and can provide an XMPP interface to existing microblogging services (which may also be accessible via HTTP, Short Message Service (SMS), and other message transports).</p>
</section1>
<section1 topic='Protocol' anchor='proto'>
<section2 topic='Location' anchor='location'>
<p>A person's microblog SHOULD be located at a personal eventing (PEP) node whose name is "urn:xmpp:microblog:0" but MAY be located at a generic publish-subscribe node that is not attached to a user's IM account. For instance, if the Shakespearean character Romeo has a JabberID of &lt;romeo@montague.lit&gt; then his microblog would be located at that JID with a node of "urn:xmpp:microblog:0". Outside of native XMPP systems, this node can be referred to as the following XMPP URI (the ":" character from the namespace URN is percent-encoded in the query component; see &rfc5122; and &rfc3986;).</p>
<code><![CDATA[
xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0
]]></code>
<p>Naturally, this node can be discovered by contacting romeo@montague.lit directly using &xep0030;.</p>
</section2>
<section2 topic='Subscribing to a Microblog' anchor='subscribe'>
<p>Let us imagine that Juliet wishes to receive the posts that Romeo publishes to his microblog. She has two options:</p>
<ol>
<li>Implicitly subscribe by advertising support for "urn:xmpp:microblog:0+notify" in her &xep0115; data. Romeo's PEP service then automatically sends posts to her when it receives presence from her, until and unless she sends presence of type unavailable or stops advertising an interest in microblog updates.</li>
<li>Explicitly subscribe by sending a formal subscription request to the "urn:xmpp:microblog:0" node at Romeo's JabberID. Romeo's PEP service may send her all posts even if she is offline at the time (depending on service policies regarding presence integration).</li>
</ol>
</section2>
<section2 topic='Publishing a Post' anchor='publish'>
<p>Romeo can publish a post via any interface provided by his service, such as a website, the Atom Publishing Protocol (see &rfc5023;), SMS, an IM bot, or XMPP pubsub. Here we assume that the post is provided via XMPP pubsub.</p>
<p>The post content itself can be either text ("content" element "type" attribute with "text" value) or XHTML ("content" element "type" attribute with "xhtml" value). If Romeo publishes XHTML content, his client MUST publish two "content" elements: a text one, and a XHTML one. For XHTML publishing, see &xep0060;.</p>
<p>Note: Publishing via HTTP, AtomPub, SMS, or IM bot is simpler for the client (e.g., because the client does not need to generate an Item ID).</p>
<example caption="Publishing a post"><![CDATA[
<iq from='romeo@montague.lit/pda'
id='pub1'
to='romeo@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0'>
<item id='1cb57d9c-1c46-11dd-838c-001143d5d5db'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>hanging out at the Caf&amp;#233; Napolitano</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/romeo/posts/1cb57d9c-1c46-11dd-838c-001143d5d5db'/>
<link rel='alternate'
href='xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=1cb57d9c-1c46-11dd-838c-001143d5d5db'/>
<id>tag:montague.lit,2008-05-08:posts-1cb57d9c-1c46-11dd-838c-001143d5d5db</id>
<published>2008-05-08T18:30:02Z</published>
<updated>2008-05-08T18:30:02Z</updated>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
</section2>
<section2 topic='Receiving a Post' anchor='receive'>
<p>Because Juliet has sent presence to Romeo including Entity Capabilities data that encapsulates the "urn:xmpp:microblog:0+notify" feature, Romeo's XMPP server will send a PEP notification to Juliet. The notification can include an XMPP message body for backwards-compatibility with Jabber clients that are not pubsub-capable (see <a href="#body">Message Body</a>).</p>
<example caption="Receiving a post"><![CDATA[
<message from='romeo@montague.lit'
to='juliet@capulet.lit'
type='headline'>
<body>hanging out at the Caf&amp;#233; Napolitano</body>
<event xmlns='http://jabber.org/protocol/pubsub#event'>
<items node='urn:xmpp:microblog:0'>
<item id='1cb57d9c-1c46-11dd-838c-001143d5d5db'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>hanging out at the Caf&amp;#233; Napolitano</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/romeo/posts/1cb57d9c-1c46-11dd-838c-001143d5d5db'/>
<link rel='alternate'
href='xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=1cb57d9c-1c46-11dd-838c-001143d5d5db'/>
<id>tag:montague.lit,2008-05-08:posts-1cb57d9c-1c46-11dd-838c-001143d5d5db</id>
<published>2008-05-08T18:30:02Z</published>
<updated>2008-05-08T18:30:02Z</updated>
</entry>
</item>
</items>
</event>
</message>
]]></example>
</section2>
<section2 topic='Replying to a Post' anchor='reply'>
<p>Anyone can publish a post in reply to Romeo's post. Here we assume that a reply comes from Benvolio.</p>
<p>Note: Inclusion of the &lt;in-reply-to/&gt; element defined in &rfc4685; indicates the post to which the user is replying. This reply includes two such elements (one pointing to the HTTP URL for the post and the other pointing to the XMPP URI for the post.</p>
<example caption="Publishing a reply"><![CDATA[
<iq from='benvolio@montague.lit/mobile'
id='uv2x37s5'
to='benvolio@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0'>
<item id='c4145006-1c53-11dd-b2d5-000bcd82471e'>
<entry xmlns='http://www.w3.org/2005/Atom'
xmlns:thr='http://purl.org/syndication/thread/1.0'>
<source>
<author>
<name>Benvolio Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>@romeo cappuccino this late in the day?</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/benvolio/posts/c4145006-1c53-11dd-b2d5-000bcd82471e'/>
<link rel='alternate'
href='xmpp:benvolio@montague.lit?;
node=urn%3Axmpp%3Amicroblog%3A0;
item=c4145006-1c53-11dd-b2d5-000bcd82471e'/>
<id>tag:montague.lit,2008-05-08:posts-c4145006-1c53-11dd-b2d5-000bcd82471e</id>
<published>2008-05-08T18:31:21Z</published>
<updated>2008-05-08T18:31:21Z</updated>
<thr:in-reply-to
ref='tag:montague.lit,2008-05-08:posts-1cb57d9c-1c46-11dd-838c-001143d5d5db'
type='application/xhtml+xml'
href='http://montague.lit/romeo/posts/1cb57d9c-1c46-11dd-838c-001143d5d5db'/>
<thr:in-reply-to
ref='tag:montague.lit,2008-05-08:posts-1cb57d9c-1c46-11dd-838c-001143d5d5db'
href='xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=1cb57d9c-1c46-11dd-838c-001143d5d5db'/>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
<p>Assuming that Romeo has also shared presence with Benvolio and has advertised support for "urn:xmpp:microblog:0+notify", he will receive the reply that Benvolio sent.</p>
</section2>
<section2 topic='Repeating a Post' anchor='repeat'>
<p>When Benvolio wants to repeat a Romeo's post, his client publishes the same post under a different name. But to be able to track the repeated post original author, Benvolio's client MAY use two specific &lt;author /&gt; child nodes, &lt;name /&gt; and &lt;uri /&gt;, containing, respectively, the name of the original post author, and his XMPP URI (JID).</p>
<p>If a comments link is present (see the <link url='#post_comments'>Post Comments</link> section of this document), the client SHOULD repeat it to keep the same discussion about the post.</p>
<example caption="Repeating a Post"><![CDATA[
<iq from='benvolio@montague.lit/mobile'
id='pub2'
to='benvolio@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0'>
<item id='1re57d3c-1q46-11dd-748r-024943d2d5rt'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>hanging out at the Caf&amp;#233; Napolitano</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/benvolio/posts/1re57d3c-1q46-11dd-748r-024943d2d5rt'/>
<link rel='alternate'
href='xmpp:benvolio@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=1re57d3c-1q46-11dd-748r-024943d2d5rt'/>
<id>tag:montague.lit,2008-05-08:posts-1re57d3c-1q46-11dd-748r-024943d2d5rt</id>
<published>2008-05-08T18:30:02Z</published>
<updated>2008-05-08T18:32:02Z</updated>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
<p>Thus, a different author JID value lets the client know the microblog item has been repeated from another one.</p>
</section2>
<section2 topic='Attaching files to a Post' anchor='attach'>
<p>Romeo might want to attach some files, such as pictures of his last vacations, or documents he wants to share. For each file to publish, Romeo's client MUST add a &lt;link /&gt; element. The "href" and "rel" attributes MUST be added; the "title", "type" and "length" ones MIGHT be added.</p>
<example caption="Attaching some files to a Post"><![CDATA[
<iq from='romeo@montague.lit/pda'
id='pub3'
to='romeo@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0'>
<item id='1df87v1q-2d12-43se-761w-318790d3g1sq'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>Beautiful Eiffel Tower!</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/romeo/posts/1df87v1q-2d12-43se-761w-318790d3g1sq'/>
<link rel='alternate'
href='xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=1df87v1q-2d12-43se-761w-318790d3g1sq'/>
<link rel='enclosure'
title='Head in the clouds'
type='image/jpeg'
length='156732'
href='http://montague.lit/romeo/files/uei8327hdz12.jpg'>
<link xmlns='urn:xmpp:microblog:0'
rel='self'
title='thumb'
type='image/jpeg'
length='31723'
href='http://montague.lit/romeo/files/uei8327hdz12_thumb.jpg'/>
</link>
<link rel='enclosure'
title='Trip report'
type='application/pdf'
length='67123'
href='http://montague.lit/romeo/files/82he1oh2084s.pdf'/>
<id>tag:montague.lit,2008-05-08:posts-1df87v1q-2d12-43se-761w-318790d3g1sq</id>
<published>2008-05-08T18:35:02Z</published>
<updated>2008-05-08T18:35:02Z</updated>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
<p>If client can generate some thumbnails images of the attached file (for pictures, videos or documents), it MAY create one or more &lt;link /&gt; sub-elements to the parent file &lt;link /&gt; element. It MUST set "xmlns" attribute to "urn:xmpp:microblog:0"; "rel" attribute to "self"; "title" attribute to "thumb"; "href" to the path of the thumbnail image. It SHOULD also have a "type" attribute specifying the thumbnail file MIME type.</p>
</section2>
</section1>
<section1 topic='Comments' anchor='comments'>
<p>Juliet and Benvolio may want to discuss about latest Romeo's post. Romeo's client MIGHT add a <link /> element to the PubSub item. The element MUST have "rel", "title" and "href" attributes, where "rel" MUST have the "replies" value; "title" MUST have the "comments" value; "href" MUST be an XMPP URI (see &rfc5122; and &rfc3986;).</p>
<section2 topic='Post Comments' anchor='post_comments'>
<p>We assume Romeo's client first created a comments node (named "urn:xmpp:microblog:0:comments/ID", where "ID" is the microblog item ID, or the SHA-1 encoded attachement URI, as defined in &rfc3174;), with defaults "pubsub#access_model" and "pubsub#publish_model" privacy settings (see &xep0060; for node creation and configuration).</p>
<example caption="Adding a comments link to a Post"><![CDATA[
<iq from='romeo@montague.lit/pda'
id='pub4'
to='romeo@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0'>
<item id='2ze57d9c-1c46-21df-830c-002143d3d2qgf'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>hanging out at the Caf&amp;#233; Napolitano</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/romeo/posts/2ze57d9c-1c46-21df-830c-002143d3d2qgf'/>
<link rel='alternate'
href='xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=2ze57d9c-1c46-21df-830c-002143d3d2qgf'/>
<link rel='replies'
title='comments'
href='xmpp:pubsub.montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0%3Acomments%2Fdd88c9bc58886fce0049ed050df0c5f2'/>
<id>tag:montague.lit,2008-05-08:posts-2ze57d9c-1c46-21df-830c-002143d3d2qgf</id>
<published>2008-05-08T18:38:02Z</published>
<updated>2008-05-08T18:38:02Z</updated>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
<p>If the comment to publish is the first item of the node, the client MAY add a "link" element, with the "rel=start" attribute. In this way, clients can determine which comment is the first one of a discussion.</p>
</section2>
<section2 topic='Attachement Comments' anchor='attachement_comments'>
<p>As we do for <link url='#post_comments'>Post Comments</link>, Romeo's client MAY create one comments PubSub node for each attachement of a post (see section of <link url='#attach'>Attaching files to a Post</link> of this document).</p>
<p>The element to create MUST be children of the parent "link" element of the attachement. Some attributes differ from the original commenting specification: "xmlns" attribute MUST be set to value "urn:xmpp:microblog:0"; "title" attribute MUST be set to value "comments_file".</p>
<example caption="Adding a comments link to an Attachement"><![CDATA[
<iq from='romeo@montague.lit/pda'
id='pub5'
to='romeo@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0'>
<item id='1af87d4i-3f09-41gt-871e-098182g4b2az'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>I love cranberries!</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/romeo/posts/1af87d4i-3f09-41gt-871e-098182g4b2az'/>
<link rel='alternate'
href='xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=1af87d4i-3f09-41gt-871e-098182g4b2az'/>
<link rel='enclosure'
title='Delicious'
type='image/jpeg'
length='91741'
href='http://montague.lit/romeo/files/efoq9172kwq.jpg'>
<link xmlns='urn:xmpp:microblog:0'
rel='replies'
title='comments_file'
href='xmpp:pubsub.montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0%3Acomments%2Fa9fe0b44ea62c6be71fac8471696fece'/>
</link>
<id>tag:montague.lit,2008-05-08:posts-1af87d4i-3f09-41gt-871e-098182g4b2az</id>
<published>2008-05-08T18:54:02Z</published>
<updated>2008-05-08T18:54:02Z</updated>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
</section2>
<section2 topic='Adding a comment' anchor='comment_add'>
<p>If Juliet wants to comment Romeo's latest post, her client MUST then send a new Atom entry to the defined PubSub node.</p>
<p>Note: A comments node SHOULD be located at a generic publish-subscribe node that is not attached to a user's IM account, but MAY be located at a personal eventing (PEP) node.</p>
<example caption="Adding a comment to a comments node"><![CDATA[
<iq from='juliet@capulet.lit/pc'
id='comment1'
to='pubsub.capulet.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0:comments/dd88c9bc58886fce0049ed050df0c5f2'>
<item id='b2106a80de39ef5ec6b8f7b69cb610c2'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Juliet Capulet</name>
<uri>xmpp:juliet@capulet.lit</uri>
</author>
</source>
<content type='text'>She is so pretty!</content>
<published>2008-05-08T18:39:02Z</published>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
<p>If Benvolio wants to retrieve the comments node, his client will send a standard PubSub stanza to request all items (see &xep0060; for all items retrieving).</p>
</section2>
</section1>
<section1 topic='Geotagging' anchor='geotagging'>
<p>Juliet may want to know which places are Romeo's notices related to. That's why Romeo's client MIGHT geotag microblog entries, using the &xep0080; protocol for storing geolocation informations.</p>
<p>Romeo's client MUST create a "geoloc" element, with the &xep0080; reference namespace: "http://jabber.org/protocol/geoloc".</p>
<example caption="Geotagging a Post"><![CDATA[
<iq from='romeo@montague.lit/mobile'
id='pub7'
to='romeo@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0'>
<item id='1zr23z8a-3g12-34fh-750b-120867gjc1sqh'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
<content type='text'>Is lost in the forest. Need help!</content>
<link rel='alternate'
type='text/html'
href='http://montague.lit/romeo/posts/1zr23z8a-3g12-34fh-750b-120867gjc1sqh'/>
<link rel='alternate'
href='xmpp:romeo@montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0;item=1zr23z8a-3g12-34fh-750b-120867gjc1sqh'/>
<link rel='replies'
title='comments'
href='xmpp:pubsub.montague.lit?;node=urn%3Axmpp%3Amicroblog%3A0%3Acomments%2F36ec6dfe61e52b1e2cdb248823520233'/>
<id>tag:montague.lit,2008-05-08:posts-1zr23z8a-3g12-34fh-750b-120867gjc1sqh</id>
<published>2008-05-08T18:43:01Z</published>
<updated>2008-05-08T18:43:01Z</updated>
<geoloc xmlns="http://jabber.org/protocol/geoloc">
<lat>48.171761</lat>
<lon>-3.3667986</lon>
<country>France</country>
<countrycode>FR</countrycode>
<region>Brittany</region>
</geoloc>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
</section1>
<section1 topic='Microblog informations' anchor='informations'>
<p>Romeo may want to publish some informations about his microblog, such as its title, an alternate web-version URI or the last time it was updated.</p>
<p>Romeo's client MAY publish these informations once he defined them. If so, his client MUST send them to the "urn:xmpp:microblog:0:informations" node, containing one only item, with the ID set to "0".</p>
<example caption="Publishing microblog informations"><![CDATA[
<iq from='romeo@montague.lit/pc'
id='pub8'
to='romeo@montague.lit'
type='set'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<publish node='urn:xmpp:microblog:0:informations'>
<item id='0'>
<entry xmlns='http://www.w3.org/2005/Atom'>
<source>
<title>Romeo&amp;apos;s Microblog</title>
<link href='http://montague.lit/romeo'/>
<id>tag:montague.lit,2008:home</id>
<updated>2008-05-08T18:30:02Z</updated>
<author>
<name>Romeo Montague</name>
<uri>xmpp:romeo@montague.lit</uri>
</author>
</source>
</entry>
</item>
</publish>
</pubsub>
</iq>
]]></example>
</section1>
<section1 topic='Notifications' anchor='body'>
<p>When replying to a comment, it is RECOMMENDED the user's client send a notification to the people who commented on the comments node, as defined in a forthcoming specification currently located at &lt;<link url='http://xmpp.org/extensions/inbox/notification-inbox.html'>http://xmpp.org/extensions/inbox/notification-inbox.html</link>&gt;.</p>
<p>When quoting an user's name (e.g., by using @user tag), it is also RECOMMENDED to send a similar notification.</p>
</section1>
<section1 topic='Message Body' anchor='body'>
<p>Depending on service policies and the value of the "pubsub#include_body" node configuration option, microblogging notifications SHOULD include a message &lt;body/&gt; element for backwards-compatibility with Jabber clients that are not pubsub-capable. It is RECOMMENDED for the XML character value of the &lt;body/&gt; element to be the same as that of the &lt;content/&gt; child of the Atom &lt;entry/&gt;.</p>
</section1>
<section1 topic='Security Considerations' anchor='security'>
<section2 topic='Comment author' anchor='comment_author'>
<p>The client SHOULD check that the comment author informations (provided in the "author" element) are valid, by checking that the "publisher" item attribute value matches the "uri" element value. If there is a difference, the comment MIGHT be displayed, but it is RECOMMENDED to specify there is a security problem.</p>
</section2>
</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>The &REGISTRAR; is requested to issue an initial namespace of "urn:xmpp:microblog:0".</p>
</section1>
<section1 topic='XML Schema' anchor='schema'>
<p>This specification re-uses the schema for the Atom content format, i.e., the 'http://www.w3.org/2005/Atom' namespace (see <cite>RFC 4287</cite>).</p>
</section1>
<section1 topic='Acknowledgements' anchor='ack'>
<p>Thanks to Ralph Meijer and Paul Scott for their suggestions.</p>
</section1>
</xep>