Overview

FBJS is the Facebook JavaScript container, enabling Facebook applications to add JavaScript to their UI components. An important use of FBJS is in making Ajax calls back to the application. FBJS introduces a set of requirements for applications that use JavaScript that are specific to FBJS. In a sense, FBJS introduces a "container" in the same way that OpenSocial uses a "container" to run JavaScript. When the application is built, reference are made to JavaScript classes that are provided by Ringside or by Facebook when the application is rendered to the user. See the Facebook Developer Wiki for more information on FBJS usage.

Design

Implementing FBJS requires the following:

• The implementation of the classes and extension methods (the "FBJS container") in JavaScript
• The integration of the container into the application rendering
• JavaScript "sandboxing" to isolate any Ringside JavaScript from any application JavaScript
• An Ajax proxy that will decorate a JavaScript request with the social Application Context