What is the simplest URL shortener application one could write in python for the Google App Engine?

Question

Services like bit.ly are great for shortening URL’s that you want to include in tweets and other conversations. What is the simplest URL shortener application one could write in python for the Google App Engine?

Answer 1

That sounds like a challenge!

from google.appengine.ext import db
from google.appengine.ext import webapp
from google.appengine.ext.webapp import run_wsgi_app

class ShortLink(db.Model):
  url = db.TextProperty(required=True)

class CreateLinkHandler(webapp.RequestHandler):
  def post(self):
    link = ShortLink(url=self.request.POST['url'])
    link.put()
    self.response.out.write("%s/%d" % (self.request.host_url, link.key().id())

  def get(self):
    self.response.out.write('<form method="post" action="/create"><input type="text" name="url"><input type="submit"></form>')

class VisitLinkHandler(webapp.RequestHandler):
  def get(self, id):
    link = ShortLink.get_by_id(int(id))
    if not link:
      self.error(404)
    else:
      self.redirect(link.url)

application = webapp.WSGIApplication([
    ('/create', CreateLinkHandler),
    ('/(\d+)', VisitLinkHandler),
])

def main():
  run_wsgi_app(application)

if __name__ == "__main__":
  main()

Answer 2

similar, complete with GAE project boilerplate: https://github.com/dustingetz/vanity-redirect