Facebook Developers

    def check_connect_session(self, request):
        """
        For use in a facebook Connect application running in Google App Engine
        Takes a Google App Engine Request
        http://code.google.com/appengine/docs/webapp/requestclass.html
        and determines if the current user has a valid session
        """

        # our session is stored in cookies - validate them
        params = self.validate_cookie(request.cookies)
        
        if not params:
            return False

        if params.get('expires'):
            self.session_key_expires = int(params['expires'])

        if 'session_key' in params and 'user' in params:
            self.session_key = params['session_key']
            self.uid = params['user']
        else:
            return False

        return True


    def validate_cookie(self, cookies):
        """
        Validates parameters passed to a Facebook connect app through cookies

        """
        # check for the hashed secret
        if self.api_key not in cookies:
            return None

        # create a dict of the elements that start with the api_key
        # the resultant dict removes the self.api_key from the beginning
        args = dict([(key[len(self.api_key) + 1:], value) 
                        for key, value in cookies.items() 
                        if key.startswith(self.api_key + "_")])

        # check the hashes match before returning them
        if self._hash_args(args) == cookies[self.api_key]:
            return args

        return None

class MainPage(webapp.RequestHandler):
    def post(self):
        self.get()

    def get(self):

        facebookapi = Facebook(API_KEY, SECRET);

        if not facebookapi.check_connect_session(self.request):
            path = os.path.join(os.path.dirname(__file__), 'templates/login.html')
            self.response.out.write(template.render(path, {'apikey': API_KEY}))
            return

        user = facebookapi.users.getInfo( 
            [facebookapi.uid], 
            ['uid', 'name', 'birthday', 'relationship_status'])[0]

        template_values = {
            'name': user['name'],
            'birthday': user['birthday'],
            'relationship_status': user['relationship_status'],
            'uid': user['uid'],
            'apikey': API_KEY
          }

        path = os.path.join(os.path.dirname(__file__), 'templates/index.html')
        self.response.out.write(template.render(path, template_values))