The WSGIApplication Class

The google.appengine.ext.webapp package provides the following classes:

class WSGIApplication(url_mapping, debug=False)

A WSGI-compatible application that maps URL paths to RequestHandler classes. An App Engine CGI script creates a WSGIApplication object, then runs it using a WSGI CGI handler such as run_wsgi_app().


A mapping of URL paths to request handlers, as a list of tuples where each tuple is a path-to-handler mapping. The first element of the tuple specifies the URL path as a string. The second element of the tuple is the constructor of a request handler class, a subclass of RequestHandler.
If True, the application runs in "debug mode." Primarily, this means that the request handler's handle_exception() method is called with debug_mode=True when the handler raises an exception, which prints debugging information to the web browser. This information will include a traceback showing fragments of your application's source code, which may contain sensitive information such as passwords. You should never deploy an application with debug_mode=True