App engine support for Third Party token for API access

Question

I have hosted a web service on App engine cloud endpoint. The APIs are protected by Auth2.0 as google say but for google accounts. What I want to achieve is allow these APIs to be accessed using 3rd party tokens. Lets say I have my on Authentication server also providing User Management. I want my google endpoint APIs to be access based on the 3rd party token I provide at the time of API call.

1. Is this possible?
2. If Yes, Where should I write the mechanism to verify the clients authenticity and hint of how its to be done.
3. Also is there any demo project available that provides user management and authentication server and returns a token that can be accepted by App Engine.

Answer 1

1. Yes
2. On your app engine project, create the authentication mechanism to validate clients.
3. As such, there is no single solution available for User management, Authentication Server and Token Issuance, but separate modules are easily available.