gdata_feedfetcher/step2.py

   1 # Copyright (C) 2008 Google Inc.
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #      http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15
  16 __author__ = 'api.jscudder (Jeff Scudder)'
  17
  18
  19 import wsgiref.handlers
  20 from google.appengine.ext import webapp
  21 from google.appengine.api import users
  22 import atom.url
  23 import gdata.service
  24 import gdata.alt.appengine
  25 import settings
  26
  27
  28 class Fetcher(webapp.RequestHandler):
  29
  30   def get(self):
  31     # Write our pages title
  32     self.response.out.write("""<html><head><title>
  33         Google Data Feed Fetcher: read Google Data API Atom feeds</title>""")
  34     self.response.out.write('</head><body>')
  35     # Allow the user to sign in or sign out
  36     next_url = atom.url.Url('http', settings.HOST_NAME, path='/step2')
  37     if users.get_current_user():
  38       self.response.out.write('<a href="%s">Sign Out</a><br>' % (
  39           users.create_logout_url(str(next_url))))
  40     else:
  41       self.response.out.write('<a href="%s">Sign In</a><br>' % (
  42           users.create_login_url(str(next_url))))
  43
  44     # Initialize a client to talk to Google Data API services.
  45     client = gdata.service.GDataService()
  46     gdata.alt.appengine.run_on_appengine(client)
  47
  48     session_token = None
  49     # Find the AuthSub token and upgrade it to a session token.
  50     auth_token = gdata.auth.extract_auth_sub_token_from_url(self.request.uri)
  51     if auth_token:
  52       # Upgrade the single-use AuthSub token to a multi-use session token.
  53       session_token = client.upgrade_to_session_token(auth_token)
  54     if session_token and users.get_current_user():
  55       # If there is a current user, store the token in the datastore and
  56       # associate it with the current user. Since we told the client to
  57       # run_on_appengine, the add_token call will automatically store the
  58       # session token if there is a current_user.
  59       client.token_store.add_token(session_token)
  60     elif session_token:
  61       # Since there is no current user, we will put the session token
  62       # in a property of the client. We will not store the token in the
  63       # datastore, since we wouldn't know which user it belongs to.
  64       # Since a new client object is created with each get call, we don't
  65       # need to worry about the anonymous token being used by other users.
  66       client.current_token = session_token
  67
  68     self.response.out.write('<div id="main"></div>')
  69     self.response.out.write(
  70         '<div id="sidebar"><div id="scopes"><h4>Request a token</h4><ul>')
  71     self.response.out.write('<li><a href="%s">Google Documents</a></li>' % (
  72         client.GenerateAuthSubURL(
  73             next_url,
  74             ('http://docs.google.com/feeds/',), secure=False, session=True)))
  75     self.response.out.write('</ul></div><br/><div id="tokens">')
  76
  77
  78 def main():
  79   application = webapp.WSGIApplication([('/.*', Fetcher),], debug=True)
  80   wsgiref.handlers.CGIHandler().run(application)
  81
  82
  83 if __name__ == '__main__':
  84   main()