Can I run locally and debug a Web App that uses Google API's? [GWT+GAE]

I'm working on a web-app using Google App Engine with GWT, and I need to use Google API's (Google Calendar, Documents and so...).

As I know, I must configure a domain with Google to set my domain as callback of an OAuth Authentication. Am I right?

If so, am I forced to deploy on GAE to test? I开发者_Python百科 mean, I can't run locally because my localhost can't be a valid callback.

Do you know any way to debug locally even using Google API's?

I have recommended to config a DynDNS, but isn't a solution in short term (incompatible router)...

If you use AuthSub instead I don't think you need to register a domain. The user just need a google account.

I have in the past used AuthSub together with Google Docs/Spreadsheet APIs on GAE and also been able to test it locally.

I can unfortunately not give you my code and exact solution (it was a while ago). But one of the samples I used extensively to base my code on was the FetcherServlet, check this code out:

http://code.google.com/p/google-app-engine-samples/source/browse/trunk/retrieving-gdata-feeds-java/src/com/google/appengine/demo/web/FetcherServlet.java?r=122

Also, I guess you might already have read this page (but their FetcherServlet uses OAuth, not AuthSub), so maybe just use it for some background info:

http://code.google.com/appengine/articles/java/retrieving_gdata_feeds.html