gistfile1.py

import os
import datetime
import webapp2
import jinja2
from google.appengine.ext import db

template_dir = os.path.join((os.path.dirname(__file__), 'templates'))
jinja_env = jinja2.Environment(loader = jinja2.FileSystemLoader(template_dir),
                                autoescape = True)


def render_str(template, **parms):
    templ = jinja_env.get_template(template)
    return templ.render(parms)

class BaseHandler(webapp2.RequestHandler):
    def render(self, template,**kw):
        self.response.out.write(render_str(template, **kw))

    def write(self, *a, **kw):
        self.response.out.write(*a, **kw)

class MainPage(BaseHandler):
    def get(self):
        posts = Post.all()
        posts.order('-posted')
        posts.run()
        self.render('index.html', posts=posts)

class Post(db.Model):
    subject = db.StringProperty(required = True)
    content = db.TextProperty(required = True)
    posted = db.DateTimeProperty()

class BlogPost(BaseHandler):
    def get(self, post_id):
        post = Post.get_by_id(int(post_id))
        self.render('post.html', post = post)

class NewPost(BaseHandler):
    def get(self):
        self.render('newpost.html')
    def post(self):
        subject = self.request.get('subject')
        content = self.request.get('content')
        params = dict(subject = subject, content = content )

        if not (subject or content):
            params['error'] = 'something is wrong'
            self.render('newpost.html', **params)
        else:
            posted = datetime.datetime.now()
            post = Post(subject=subject,
                        content=content,
                        posted = posted)
            post.put()
            post_id = post.key().id()
            self.redirect('/blog/%s'%post_id)

app = webapp2.WSGIApplication([('/blog', MainPage),
                               ('/blog/newpost', NewPost),
                               (r'/blog/(\d+)', BlogPost)])