Running on Google App Engine

App Engine-specific helpers make quick work of authenticated calls to APIs, and you do not need to worry about exchanging code for tokens.

For example:

  @Override 
 protected 
 void 
 doGet 
 ( 
 HttpServletRequest 
 req 
 , 
 HttpServletResponse 
 resp 
 ) 
 throws 
 IOException 
 { 
 AppIdentityCredential 
 credential 
 = 
 new 
 AppIdentityCredential 
 ( 
 Arrays 
 . 
 asList 
 ( 
 UrlshortenerScopes 
 . 
 URLSHORTENER 
 )); 
 Urlshortener 
 shortener 
 = 
 new 
 Urlshortener 
 . 
 Builder 
 ( 
 new 
 UrlFetchTransport 
 (), 
 new 
 JacksonFactory 
 (), 
 credential 
 ) 
 . 
 build 
 (); 
 UrlHistory 
 history 
 = 
 shortener 
 . 
 URL 
 (). 
 list 
 (). 
 execute 
 (); 
 ... 
 } 
 

Auth helpers

If you are building a web app that interacts with a user’s data via an OAuth 2.0-enabled API, we’ve created some helpers to assist you with the process. The helpers aim to:

• Simplify the process of obtaining access tokens ( AuthorizationCodeFlow ).
• Manage tokens, after they are obtained, by marking them as PersistenceCapable .
• Simplify the process of making authenticated calls using the access token’s credential .
• Insulate you from the details of authentication when writing servlets.

Getting started

1. Install the Google API Client Library for Java:
   • Follow the download instructions and put the library jar files into your war/WEB-INF/lib directory.
   • Alternatively, you can use Maven .
2. Learn about using OAuth 2.0 with the authorization code flow for Google App Engine applications .
3. Learn about using OAuth 2.0 with the Google App Engine Identity API .
4. Take a look at the Calendar App Engine sample . This sample combines our Java library and auth helpers to show you how to access end-user data from within a Google App Engine web app. The sample also uses GWT for the user interface.