App Engine Python Flexible Environment Selecting A Runtime

Question

I can run my app locally using dev_appserver.py app.yaml

And my app works. However, when I try to deploy to app engine, I'm given the following warning: WARNING: [runtime: python-compat]is deprecated. Please use [runtime: python] instead. See https://cloud.google.com/appengine/docs/flexible/python/migrating for more info. I tried using runtime: python, however when I do so nothing works locally. Also, when I use python-compat, I cannot deploy to app engine, I just get Updating service [default]. I'm using Python 2.7, what should I change to fix my runtime issues? app.yaml below

runtime: python-compat
env: flex
entrypoint: gunicorn -b :$PORT main:app


runtime_config:
  python_version: 2
threadsafe: true

handlers:
- url: /.*
  script: main.app

- url: /static
  static_dir: static

- url: .*
  script: main.app

Dan Cornilescu Dan Cornilescu · Accepted Answer · 2017-10-29T02:54:23

FWIW, running the app locally through dev_appserver.py is only applicable to the standard environment, you were simply lucky to be able to run it (maybe because of the now deprecated python-compat runtime?). From Using the Local Development Server:

Note: dev_appserver.py does not run in the App Engine flexible environment.

For the flexible environment you normally need to run your app the same way you'd run it on GAE, see Running locally for details. In your case it'd be:

gunicorn -b :$PORT main:app

With this in mind switching to runtime: python should no longer be an issue, you'd simply align with the official recommendations.

Side note: potentially of interest: How to tell if a Google App Engine documentation page applies to the standard or the flexible environment

App Engine Python Flexible Environment Selecting A Runtime

1 Answers