NSM Addon Updater is an EE 2.0 extension that checks an external RSS feed for version updates and displays them in your extension admin.
If you want to include NSM Addon updater support in your addon just add the following public variable to any extension class:
public $versions_xml = "http://yourdomain.com/versions.xml";
The url should point to a valid RSS 2.0 XML feed that lists individual versions of your addon as . There is only one required addition to a standard feed: <ee_addon:version>1.0.0b1</ee_addon:version> which is used for version comparison.
Each feed is individually cached so that the CURL calls don't stall the loading of the CP. Additionally the calls are made via AJAX so there should be no negative affect on CP load.
<?xml version="1.0" encoding="utf-8"?>
<rss version="2.0" xmlns:ee_addon="http://expressionengine-addons.com/nsm_addon_updater/#rss-xml">
<channel>
<title>NSM Addon Updater Changelog</title>
<link>http://yourdomain.com/nsm.addon_updater.ee_addon/appcast.xml</link>
<description>Most recent changes with links to updates.</description>
<item>
<title>Version 1.0.0b1</title>
<!-- Additional tag required for NSM Addon Updater -->
<ee_addon:version>1.0.0b1</ee_addon:version>
<link>http://yourdomain.com/nsm.addon_updater.ee_addon/1.0.0b1/</link>
<pubDate>Wed, 09 Jan 2006 19:20:11 +0000</pubDate>
<description><![CDATA[
<ul>
<li>Added the {selected_group_id} variable for available use in the User Key Notification Template.</li>
<li>Added the form:attribute="" parameter type to all User functions that output forms.</li>
</ul>
]]>
</description>
<enclosure url="http://expressionengine-addons.com/nsm.addon_updater.ee_addon/download.zip?version=1.0.0b1" length="1623481" type="application/zip" />
</item>
</channel>
</rss>