dev_appserver.py can't find pkg_resources

Question

As part of migrating from ndb to cloud-ndb with GAE Python 2, you need to add the following to appengine_config.py:

import pkg_resources
from google.appengine.ext import vendor

vendor.add('lib')
pkg_resources.working_set.add_entry('lib')

When running locally with dev_appserver.py, I get an error that pkg_resources can't be found.

How do I fix this?

Answer 1

I found out that you don't need pkg_resources when running locally with dev_appserver.py. It is only needed for deployment.

Although I couldn't fix the problem, a good workaround is to update appengine_config.py to this:

from google.appengine.ext import vendor

vendor.add('lib')

try:
    import pkg_resources
    pkg_resources.working_set.add_entry('lib')
except ImportError:
    pass

With this modification, it works both locally and when deployed.

Answer 2

As part of migrating from ndb to cloud-ndb with GAE Python 2, you need to add the following to appengine_config.py:

Was this in the docs somewhere? I'm curious what lead you to that conclusion.

I encountered a weird error with google-cloud-storage a while back on both localhost and remote

DistributionNotFound: The 'google-cloud-storage' distribution was not found and is required by the application

It seemed that I had pkg_resources in multiple places and that I needed the pkg_resources in my lib folder to be the one being loaded. I think that the google-cloud-xxxxxxx libs need pkg_resources to be in the same directory with them in order for them to work. (printing pkg_resources.__file__ shows you which pkg_resources is being picked up).

The fix for me was to do import pkg_resources & reload(pkg_resources) after vendor.add('lib'):

vendor.add('lib')

import pkg_resources
reload(pkg_resources)

I just recently migrated to google-cloud-ndb and didnt have to make any further changes in regards to pkg_resources, so now I'm thinking that reload(pkg_resources) possible saved me from the issue you were facing.