Single Sign On (SSO) with OpenID for Google Apps Marketplace

Applications on Google Apps Marketplace allow users to login with their existing Google Apps accounts using OpenID. “We chose to power our Single Sign On (SSO) using OpenID because it’s the predominant open standard for federated identity on web. Protocol is supported by a large number of OpenID identity providers and many sites accept it. […]

Applications on Google Apps Marketplace allow users to login with their existing Google Apps accounts using OpenID. “We chose to power our Single Sign On (SSO) using OpenID because it’s the predominant open standard for federated identity on web. Protocol is supported by a large number of OpenID identity providers and many sites accept it. And to make SSO easy to access, Marketplace apps also plug in to both universal navigation bar inside Gmail, Calendar, Docs, and Sites, as well as administrative control panel. To enable SSO experience for Marketplace apps, developers simply need to add a universal navigation link and an OpenID realm to their application manifest. Adding these elements is easy-- it’s just a snippet of XML:

<extension id="navLink" type="link">
  <name>Amazing Cloud App</name>      
  <url>http://www.example.com/home.php?domain=${DOMAIN_NAME}</url>
</extension>

<extension id="realm" type="openIdRealm">
  <url>http://www.example.com</url>
</extension>

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