python27/guestbook/guestbook.py

   1 import jinja2
   2 import os
   3 import webapp2
   4
   5 from google.appengine.api import users
   6 from google.appengine.ext import ndb
   7
   8
   9 # We set a parent key on the 'Greetings' to ensure that they are all in the same
  10 # entity group. Queries across the single entity group will be consistent.
  11 # However, the write rate should be limited to ~1/second.
  12
  13 def guestbook_key(guestbook_name='default_guestbook'):
  14   return ndb.Key('Guestbook', guestbook_name)
  15
  16 jinja_environment = jinja2.Environment(
  17     loader=jinja2.FileSystemLoader(os.path.dirname(__file__)),
  18     extensions=['jinja2.ext.autoescape'])
  19
  20 class Greeting(ndb.Model):
  21     author = ndb.UserProperty()
  22     content = ndb.StringProperty()
  23     date = ndb.DateTimeProperty(auto_now_add=True)
  24
  25 class MainPage(webapp2.RequestHandler):
  26     def get(self):
  27         greetings_query = Greeting.query(ancestor=guestbook_key()).order(-Greeting.date)
  28         greetings = greetings_query.fetch(10)
  29
  30         if users.get_current_user():
  31             url = users.create_logout_url(self.request.uri)
  32             url_linktext = 'Logout'
  33         else:
  34             url = users.create_login_url(self.request.uri)
  35             url_linktext = 'Login'
  36
  37         template = jinja_environment.get_template('index.html')
  38         self.response.out.write(template.render(greetings=greetings,
  39                                                 url=url,
  40                                                 url_linktext=url_linktext))
  41
  42 class Guestbook(webapp2.RequestHandler):
  43     def post(self):
  44         greeting = Greeting(parent=guestbook_key())
  45
  46         if users.get_current_user():
  47             greeting.author = users.get_current_user()
  48
  49         greeting.content = self.request.get('content')
  50         greeting.put()
  51         self.redirect('/')
  52
  53 application = webapp2.WSGIApplication(
  54                                      [('/', MainPage),
  55                                       ('/sign', Guestbook)],
  56                                      debug=True)