The app returned an error when the Google Cloud Endpoints server attempted to communicate with it

Question

Hi I'm new to Google App Engine and Cloud Endpoints.

I have an app engine that serves web application.

And I want to use it with Cloud Endpoints.

So I just added source codes from here: https://cloud.google.com/appengine/docs/python/endpoints/getstarted/backend/write_api

But I cannot deploy app and get this error message:

Checking if Endpoints configuration has been updated.
07:13 AM Failed to update Endpoints configuration.  The app returned an error when the Google Cloud Endpoints server attempted to communicate with it.
07:13 AM See the deployment troubleshooting documentation for more information: https://developers.google.com/appengine/docs/python/endpoints/test_deploy#troubleshooting_a_deployment_failure

And this is my source codes

import endpoints
from protorpc import messages
from protorpc import message_types
from protorpc import remote

package = 'Hello'


class Greeting(messages.Message):
  """Greeting that stores a message."""
  message = messages.StringField(1)


class GreetingCollection(messages.Message):
  """Collection of Greetings."""
  items = messages.MessageField(Greeting, 1, repeated=True)


STORED_GREETINGS = GreetingCollection(items=[
    Greeting(message='hello world!'),
    Greeting(message='goodbye world!'),
])


@endpoints.api(name='helloworld', version='v1')
class HelloWorldApi(remote.Service):
  """Helloworld API v1."""

  @endpoints.method(message_types.VoidMessage, GreetingCollection,
                    path='hellogreeting', http_method='GET',
                    name='greetings.listGreeting')
  def greetings_list(self, unused_request):
    return STORED_GREETINGS

  ID_RESOURCE = endpoints.ResourceContainer(
      message_types.VoidMessage,
      id=messages.IntegerField(1, variant=messages.Variant.INT32))

  @endpoints.method(ID_RESOURCE, Greeting,
                    path='hellogreeting/{id}', http_method='GET',
                    name='greetings.getGreeting')
  def greeting_get(self, request):
    try:
      return STORED_GREETINGS.items[request.id]
    except (IndexError, TypeError):
      raise endpoints.NotFoundException('Greeting %s not found.' %
                                        (request.id,))

APPLICATION = endpoints.api_server([HelloWorldApi])

exactly same with tutorial

and my app.yaml

application: my application id
version: application version
runtime: python27
api_version: 1
threadsafe: true

handlers:
- url: /data
  script: MLP.app
  login: admin
- url: /insert_db
  script: MLP.app
  login: admin
- url: /validete
  script: MLP.app
  login: admin
- url: /stylesheets
  static_dir: stylesheets
- url: /js
  static_dir: js 
- url: /.*
  script: MLP.app
- url: /_ah/spi/.*
  script: MLP_mobile_backend.APPLICATION

libraries:
- name: webapp2
  version: latest
- name: jinja2
  version: latest
- name: pycrypto
  version: latest
- name: endpoints
  version: 1.0

MLP.py is just web service with webapp2

How can I solve the problem?

I could start program locally... but I could not find any API names with helloapi that tutorial said — SounBum Song

Jeffrey Godwyll Jeffrey Godwyll · Accepted Answer · 2015-11-05T10:33:02

From the app.yaml line script: MLP_mobile_backend.APPLICATION, it means your code sample must live in a MLP_mobile_backend.py file at the root of your app engine project

.
├── app.yaml 
├── MLP.py 
└── MLP_mobile_backend.py

with an endpoint api server named APPLICATION defined in that file just as in your code sample above.

APPLICATION = endpoints.api_server([HelloWorldApi])

After those requirements are fulfilled, this line points to how to access your endpoints:

@endpoints.api(name='helloworld', version='v1')

So for example, let's say you're running your devserver's module on port 8080 and you want to access the hellogreeting path:

@endpoints.method(message_types.VoidMessage, GreetingCollection,
                  path='hellogreeting', http_method='GET',
                  name='greetings.listGreeting')

you can use cURL or httpie or your browser to locally navigate to the devserver's default module at http://localhost:8080/_ah/api/helloworld/v1/hellogreeting or with Google's API explorer at http://localhost:8080/_ah/api/explorer which should result in this response body:

{
 "items": [
  {
   "message": "hello world!"
  }, 
  {
   "message": "goodbye world!"
  }
 ]
}

Once you get it set up locally, you can then deploy it.

More here

The app returned an error when the Google Cloud Endpoints server attempted to communicate with it

1 Answers