'gcloud auth login' no longer writes application default credentials

[nhammond]

After running gcloud auth login, I see this warning:

WARNING: gcloud auth login no longer writes application default credentials.
If you need to use ADC, see:
gcloud auth application-default --help

After this, 'loom server create'. The root cause is this command:

>>> oauth2client.client.GoogleCredentials.get_application_default()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/nhammond/dev/loom-scratch/env/local/lib/python2.7/site-packages/oauth2client/client.py", line 1288, in get_application_default
    return GoogleCredentials._get_implicit_credentials()
  File "/home/nhammond/dev/loom-scratch/env/local/lib/python2.7/site-packages/oauth2client/client.py", line 1278, in _get_implicit_credentials
    raise ApplicationDefaultCredentialsError(ADC_HELP_MSG)
oauth2client.client.ApplicationDefaultCredentialsError: The Application Default Credentials are not available. They are available if running in Google Compute Engine. Otherwise, the environment variable GOOGLE_APPLICATION_CREDENTIALS must be defined pointing to a file defining the credentials. See https://developers.google.com/accounts/docs/application-default-credentials for more information.

As a workaround, you can run this:
gcloud auth application-default login

However, this issue will affect all users using a newer version of gcloud who have not already generated credentials. The current prompt asks users to 'gcloud init', but that no longer works.

[nhammond]

Current behavior is this:

gcloud auth revoke --all
loom server set gcloud --name nate-test
loom server create --settings ~/settings

Traceback (most recent call last):
  File "/Users/s0198839/dev/loom/loom-env/bin/loom", line 11, in <module>
    load_entry_point('loomengine', 'console_scripts', 'loom')()
  File "/Users/s0198839/dev/loom/loom/loomengine/client/main.py", line 72, in main
    return Main().run()
  File "/Users/s0198839/dev/loom/loom/loomengine/client/main.py", line 68, in run
    return self.args.SubcommandClass(self.args).run()
  File "/Users/s0198839/dev/loom/loom/loomengine/client/server.py", line 383, in create
    create_gce_ini(default_plus_user_settings['CUSTOM_SERVICE_ACCOUNT_EMAIL'])
  File "/Users/s0198839/dev/loom/loom/loomengine/client/common.py", line 176, in create_gce_ini
    raise Exception('Credential %s does not exist or is not valid for the current project. Please run "gcloud init" and ensure that the correct project is selected.' % GCE_JSON_PATH)
Exception: Credential ~/.loom/gce_key.json does not exist or is not valid for the current project. Please run "gcloud init" and ensure that the correct project is selected.

gcloud init
# logged in and chose settings

loom server create --settings ~/settings.ini

# Same error as above.

[nhammond]

With planned release 0.3.0, automatic service account key generation feature is removed and this issue is moot.