Rally's Ruby REST API
Rally Software Development’s on-demand agile software life-cycle management service offers webservices API’s for its customers. The API comes in both SOAP and REST style interfaces. This library is for accessing the REST API using Ruby. For more information about Rally’s webservice APIs see https://rally1.rallydev.com/slm/doc/webservice/index.jsp.
In short you don’t have to deal with WSDL.
Your subscription in Rally can be partitioned into several isolated “Workspaces”, where the only thing shared between workspaces are your users. Any custom attributes you create will be specific to each workspace. When using the SOAP interface, the WSDL generated is specific to the workspace you are working in. Therefore the name-space (e.g. package in Java) will be different for each workspace you are working with.
Because REST webservices do not have WSDL (the XML schema is available for each workspace), there is no per-workspace interface. Combined with the dynamic nature of this API, you don’t need to code to different Ruby namespaces when you are working with multiple workspaces. You will, however, need to be aware of the workspaces your objects are in when working with multiple workspaces.