Simple Channel API Related Test Failing with 1.8.2 Upgrade

Question

Ever since upgrading to Google App Engine SDK version 1.8.2 we've been having an issue with one of our Channel API related unit tests.

Here's the skinny.

We have a handler that creates a channel and returns the channel ID as well as the channel token. That handler looks something like:

import json
from uuid import uuid4
from google.appengine.api.channel import channel
import webapp2


class ChannelSubscriptionHandler(webapp2.RequestHandler):

    def get(self):
        self.response.headers['Context-Type'] = 'application/json'

        channel_id = str(uuid4())
        token = channel.create_channel(channel_id)

        self.response.write(json.dumps({
            'channel_id': channel_id,
            'token': token
        }))

app = webapp2.WSGIApplication([
    ('/channel_subscription/', ChannelSubscriptionHandler)
], debug=True)

Nothing crazy going on, just creating a channel and returning the particulars.

Then we have a unit test the exercises the handler code that looks like:

import json
from unittest import TestCase
from google.appengine.api.channel import channel
from google.appengine.ext.testbed import Testbed
from webtest import TestApp
import example_channel_api_handler


class ChannelSubscriptionHandlerTests(TestCase):

    def setUp(self):
        self.testbed = Testbed()
        self.testbed.activate()
        self.testbed.init_channel_stub()

        self.channel_stub = self.testbed.get_stub('channel')

        self.app = TestApp(example_channel_api_handler.app)

    def test_can_get_channel_subscription(self):

        response = self.app.get('/channel_subscription/', status=200)

        data = json.loads(response.body)

        token = data.get('token', None)
        channel_id = data.get('channel_id', None)

        self.assertIsNotNone(token)
        self.assertIsNotNone(channel_id)

        self.channel_stub.connect_channel(token)

        channel.send_message(channel_id, 'Hello World')

        self.assertEquals(['Hello World'], self.channel_stub.get_channel_messages(token))

Like I said above, up until version 1.8.2 of the GAE SDK the above test worked like a charm. I scanned the release notes for the latest release and did see some Channel API related stuff, but it didn't look like it applied to the issue that I'm having.

Also, the above code isn't really from the application that I'm working on, but it replicates the issue as I have described it.

Finally, it doesn't appear that the application is broken in production, it's like this issue revolves around the testbed for the Channel API.

Thanks for reading.

Answer 1

I logged this as an issue on the Google App Engine SDK issue tracker.

The issue I logged is mentioned in the original comments.

The issue was accepted and is scheduled to be fixed in the next (1.8.3) release of the Google App Engine SDK.

Thanks for reading.