terom@7: 
terom@7: """
terom@7:     WSGI application implementation
terom@7: """
terom@7: 
terom@7: # for error reporting
terom@7: import sys, traceback
terom@7: 
terom@7: # for Request/Response
terom@7: import http
terom@7: 
terom@31: class Application (object) :
terom@7:     """
terom@31:         Our WSGI application, implements the wsgi __call__ interface
terom@7:     """
terom@7: 
terom@31:     def __init__ (self, handler) :
terom@31:         """
terom@31:             Initialize to use the given handler for requests
terom@31:         """
terom@30: 
terom@31:         self.handler = handler
terom@7:     
terom@31:     def handle_request (self, env, start_response) :
terom@31:         """
terom@31:             The actual request handling code
terom@31:         """
terom@7: 
terom@31:         # build Request object
terom@31:         request = http.Request(env)
terom@7: 
terom@31:         try :
terom@31:             # request -> response using our handler
terom@31:             response = self.handler.handle_request(request)
terom@7: 
terom@31:         except http.ResponseError, err :
terom@31:             # just use the generated response
terom@31:             response = err.get_response()
terom@7: 
terom@31:         # send response
terom@31:         assert response, "No response"
terom@31:         
terom@31:         # send response status/headers
terom@31:         start_response(response.get_status(), response.get_headers())
terom@7: 
terom@31:         # send respones data
terom@31:         yield response.get_data()
terom@31: 
terom@72:     def handle_error (self, exc_info, env, start_response) :
terom@72:         """
terom@72:             Handle errors thrown by handle_request. This should call start_response with the exc_info and return the
terom@72:             error message (i.e. str), otherwise the error will be thrown up yet another level.
terom@72: 
terom@72:             Note that e.g. unicode is a failure...
terom@72:         """
terom@72: 
terom@72:         # try and send 500 ISE to browser, if no headers yet...
terom@72:         start_response("500 Internal Server Error", [('Content-type', "text/plain; charset=UTF-8")], exc_info)
terom@72: 
terom@72:         # format traceback
terom@72:         data = ''.join(traceback.format_exception(*exc_info))
terom@72:         
terom@72:         # no unicode, kplzthx
terom@72:         return data.encode('utf-8')
terom@72:     
terom@31:     def __call__ (self, env, start_response) :
terom@31:         """
terom@31:             Wraps handle_request to trap errors
terom@31:         """
terom@31: 
terom@31:         try :
terom@31:             # passthrough request_handler
terom@31:             for chunk in self.handle_request(env, start_response) :
terom@31:                 yield chunk
terom@31: 
terom@31:         except :
terom@31:             # execption info
terom@31:             info = sys.exc_info()
terom@31: 
terom@72:             # handle
terom@72:             yield self.handle_error(info, env, start_response)
terom@31: