Adding Google Signin feature with GWT and GAE

SignOn features using Google Web Services is easy and efficient way to authenticate users. It’s pretty common these days to have authentication via Google UserServices. Google App Engine provides UserServiceFactory api for this purpose. I tried implementing this API within Google Web Toolkit and here’s the code snippet for reference.

The code is divided to Server Side Code and_ Client Side Code_. Server side code provides the implementation of the actual API call while the Client side code provides interface to those RPC calls and you can make asynchronous call to the server side api. Deeper understanding of RPC call can be found in my previous weblogs.