Update Google App Engine to Python 2.7

Question

I've tried to update my app before by changing

runtime: python27 , threadsafe: true , script: main.app"

It did work and was on python 2.7 but it didn't run properly I guess because my index.html didn't display when I went to the url http://dhsenviro.appspot.com. It is running on 2.5 now (because I want to keep it up). robots.txt is empty. How can I update it to 2.7 or should I update it to 3.x?

app.yaml :

application: dhsenviro
version: 1
runtime: python
api_version: 1

handlers:
- url: /(.*\.(gif|png|jpg|ico|js|css|psd|swf))
  static_files: \1
  upload: (.*\.(gif|png|jpg|ico|js|css|psd|swf))

- url: /robots.txt
  static_files: robots.txt
  upload: robots.txt 

- url: /.*
  script: main.py

main.py :

import os
from google.appengine.ext import webapp
from google.appengine.ext.webapp import util
from google.appengine.ext.webapp import template

class MainHandler(webapp.RequestHandler):
  def get (self, q):
    if q is None:
      q = 'index.html'

    path = os.path.join (os.path.dirname (__file__), q)
    self.response.headers ['Content-Type'] = 'text/html'
    self.response.out.write (template.render (path, {}))

def main ():
  application = webapp.WSGIApplication ([('/(.*html)?', MainHandler)], debug=True)
  util.run_wsgi_app (application)

if __name__ == '__main__':
  main ()

I'd prefer not to upload my index.html, but I'm sure it's working properly.

Edit:

main.py :

import os
from google.appengine.ext import webapp
from google.appengine.ext.webapp import util
from google.appengine.ext.webapp import template

class MainHandler(webapp.RequestHandler):
  def get (self, q):
    if q is None:
      q = 'index.html'

    path = os.path.join (os.path.dirname (__file__), q)
    self.response.headers ['Content-Type'] = 'text/html'
    self.response.out.write (template.render (path, {}))

class application = webapp.WSGIApplication ([('/(.*html)?', MainHandler)], debug=True)

def main ():

if __name__ == '__main__':
  main ()

CORRECT APP.YAML :

application: dhsenviro
version: 1
runtime: python27
api_version: 1
threadsafe: true

handlers:
- url: /(.*\.(gif|png|jpg|ico|js|css|psd|swf))
  static_files: \1
  upload: (.*\.(gif|png|jpg|ico|js|css|psd|swf))

- url: /robots.txt
  static_files: robots.txt
  upload: robots.txt 

• url: /.* script: main.application

CORRECT MAIN.PY

import os
from google.appengine.ext import webapp
from google.appengine.ext.webapp import util
from google.appengine.ext.webapp import template

class MainHandler(webapp.RequestHandler):
  def get (self, q):
    if q is None:
      q = 'index.html'

    path = os.path.join (os.path.dirname (__file__), q)
    self.response.headers ['Content-Type'] = 'text/html'
    self.response.out.write (template.render (path, {}))

application = webapp.WSGIApplication ([('/(.*html)?', MainHandler)], debug=True)

Answer 1

According to Google's official Migrating to Python 2.7 doc, I think you have to do 2 things at least

• Update your app.yaml.

in GAE Python 2.5, the script attribute of the url handler is the path to the python source file.

- url: /.*
  script: main.py

in Python 2.7 , it is changed to the a object

- url: /.*
  script: myapp.app

app is a instance of the webapp2.WSGIApplication

• Updating your application to webapp2

import webapp2

class MainPage(webapp2.RequestHandler):
  def get(self):
    self.response.headers['Content-Type'] = 'text/plain'
    self.response.out.write('Hello, WebApp World!')

app = webapp2.WSGIApplication([('/', MainPage)])

""" Old code:
def main():
  run_wsgi_app(app)

if __name__ == '__main__':
  main()
"""

Though you want to keep templates unchanged, webapp templates are deprecated.

webapp templates are now deprecated. In their place, you can use Jinja2, Django, or a templating system of your choice (as long as it's written in pure Python).

Answer 2

Appengine does not support 3x (yet?). What is the error you encoutered? If it is error, should print something to the logs. A couple think that I notice,

• I don't think you need the run_wsgi_app anymore
• the script in yaml should be "main.application" instead of "main.py". Put the application variable as a global variable instead of local variable