simple-ajax-chat/devchat.py

   1 import cgi
   2 import os
   3 import urllib
   4 import logging
   5 import pickle
   6
   7 from google.appengine.api import users
   8 from google.appengine.ext import webapp
   9 from google.appengine.ext.webapp.util import run_wsgi_app
  10 from google.appengine.ext import db
  11 from google.appengine.ext.webapp import template
  12 from google.appengine.api import memcache
  13
  14 # Set the debug level
  15 _DEBUG = True
  16
  17 class GreetingUser(db.Model):
  18   greeting_user = db.UserProperty()
  19   joined = db.DateTimeProperty(auto_now_add=True)
  20   picture = db.StringProperty()
  21   seated = db.StringProperty()
  22   website = db.StringProperty()
  23
  24 class Greeting(db.Model):
  25   author = db.UserProperty()
  26   content = db.StringProperty(multiline=True)
  27   date = db.DateTimeProperty(auto_now_add=True)
  28
  29 class BaseRequestHandler(webapp.RequestHandler):
  30   """Base request handler extends webapp.Request handler
  31
  32      It defines the generate method, which renders a Django template
  33      in response to a web request
  34   """
  35
  36   def generate(self, template_name, template_values={}):
  37     """Generate takes renders and HTML template along with values
  38        passed to that template
  39
  40        Args:
  41          template_name: A string that represents the name of the HTML template
  42          template_values: A dictionary that associates objects with a string
  43            assigned to that object to call in the HTML template.  The defualt
  44            is an empty dictionary.
  45     """
  46     # We check if there is a current user and generate a login or logout URL
  47     user = users.get_current_user()
  48
  49     if user:
  50       log_in_out_url = users.create_logout_url('/')
  51     else:
  52       log_in_out_url = users.create_login_url(self.request.path)
  53
  54     # We'll display the user name if available and the URL on all pages
  55     values = {'user': user, 'log_in_out_url': log_in_out_url}
  56     values.update(template_values)
  57
  58     # Construct the path to the template
  59     directory = os.path.dirname(__file__)
  60     path = os.path.join(directory, 'templates', template_name)
  61
  62     # Respond to the request by rendering the template
  63     return template.render(path, values, debug=_DEBUG)
  64
  65 class MainRequestHandler(BaseRequestHandler):
  66   def get(self):
  67     if users.get_current_user():
  68       url = users.create_logout_url(self.request.uri)
  69       url_linktext = 'Logout'
  70     else:
  71       url = users.create_login_url(self.request.uri)
  72       url_linktext = 'Login'
  73
  74     template_values = {
  75       'url': url,
  76       'url_linktext': url_linktext,
  77       }
  78
  79     self.response.out.write(self.generate('index.html', template_values));
  80
  81 class ChatsRequestHandler(BaseRequestHandler):
  82   MEMCACHE_KEY = 'greetings'
  83   MEMCACHE_TEMPLATE = 'greetings_template'
  84
  85   def get(self):
  86     template = memcache.get(self.MEMCACHE_TEMPLATE)
  87     self.response.out.write(template)
  88
  89   def post(self):
  90     greeting = Greeting()
  91
  92     if users.get_current_user():
  93       greeting.author = users.get_current_user()
  94
  95     greeting.content = self.request.get('content')
  96     greeting.put()
  97
  98     greetingsString = memcache.get(self.MEMCACHE_KEY)
  99     if greetingsString is None:
 100       greetingsList = []
 101     else:
 102       greetingsList = pickle.loads(greetingsString)
 103       if len(greetingsList) >= 40:
 104         greetingsList.pop(0)
 105     greetingsList.append(greeting)
 106
 107     if not memcache.set(self.MEMCACHE_KEY, pickle.dumps(greetingsList)):
 108         logging.debug("Memcache set failed:")
 109
 110     template_values = {
 111       'greetings': greetingsList,
 112     }
 113     template = self.generate('chats.html', template_values)
 114     if not memcache.set(self.MEMCACHE_TEMPLATE, template):
 115         logging.debug("Memcache set failed:")
 116
 117     self.response.out.write(template)
 118
 119
 120 class EditUserProfileHandler(BaseRequestHandler):
 121   """This allows a user to edit his or her wiki profile.  The user can upload
 122      a picture and set a feed URL for personal data
 123   """
 124   def get(self, user):
 125     # Get the user information
 126     unescaped_user = urllib.unquote(user)
 127     greeting_user_object = users.User(unescaped_user)
 128     # Only that user can edit his or her profile
 129     if users.get_current_user() != greeting_user_object:
 130       self.redirect('/view/StartPage')
 131
 132     greeting_user = GreetingUser.gql('WHERE greeting_user = :1', greeting_user_object).get()
 133     if not greeting_user:
 134       greeting_user = GreetingUser(greeting_user=greeting_user_object)
 135       greeting_user.put()
 136
 137     self.response.out.write(self.generate('edit_user.html', template_values={'queried_user': greeting_user}))
 138
 139   def post(self, user):
 140     # Get the user information
 141     unescaped_user = urllib.unquote(user)
 142     greeting_user_object = users.User(unescaped_user)
 143     # Only that user can edit his or her profile
 144     if users.get_current_user() != greeting_user_object:
 145       self.redirect('/')
 146
 147     greeting_user = GreetingUser.gql('WHERE greeting_user = :1', greeting_user_object).get()
 148
 149     greeting_user.picture = self.request.get('user_picture')
 150     greeting_user.website = self.request.get('user_website')
 151     greeting_user.seated = self.request.get('user_seated')
 152     greeting_user.put()
 153
 154
 155     self.redirect('/user/%s' % user)
 156
 157 class UserProfileHandler(BaseRequestHandler):
 158   """Allows a user to view another user's profile.  All users are able to
 159      view this information by requesting http://wikiapp.appspot.com/user/*
 160   """
 161
 162   def get(self, user):
 163     """When requesting the URL, we find out that user's WikiUser information.
 164        We also retrieve articles written by the user
 165     """
 166     # Webob over quotes the request URI, so we have to unquote twice
 167     unescaped_user = urllib.unquote(urllib.unquote(user))
 168
 169     # Query for the user information
 170     greeting_user_object = users.User(unescaped_user)
 171     greeting_user = GreetingUser.gql('WHERE greeting_user = :1', greeting_user_object).get()
 172
 173     # Generate the user profile
 174     self.response.out.write(self.generate('user.html', template_values={'queried_user': greeting_user}))
 175
 176
 177 application = webapp.WSGIApplication(
 178                                      [('/', MainRequestHandler),
 179                                       ('/getchats', ChatsRequestHandler),
 180                                       ('/user/([^/]+)', UserProfileHandler),
 181                                       ('/edituser/([^/]+)', EditUserProfileHandler)],
 182                                      debug=True)
 183
 184 def main():
 185   run_wsgi_app(application)
 186
 187 if __name__ == "__main__":
 188   main()