python client: gce error on dev server

[procedurallygenerated]

I connect to the local version of my gcd using

datastore.set_options(dataset="datasetId", host="http://localhost:8888")
    try:
        # Create a RPC request to begin a new transaction.
        req = datastore.BeginTransactionRequest()
        # Execute the RPC synchronously.
        resp = datastore.begin_transaction(req)

On the last line it throws the error

File "/app/googledatastore/helper.py", line 70, in get_credentials_from_env
    credentials.refresh(http)
File "/app/oauth2client/client.py", line 516, in refresh
    self._refresh(http.request)
File "/app/oauth2client/gce.py", line 82, in _refresh
    response, content = http_request(uri)
File "/app/oauth2client/util.py", line 132, in positional_wrapper
    return wrapped(*args, **kwargs)
File "/app/oauth2client/client.py", line 475, in new_request
    self._refresh(request_orig)
File "/app/oauth2client/gce.py", line 82, in _refresh
    response, content = http_request(uri)
File "/app/httplib2/__init__.py", line 1570, in request
    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
File "/app/httplib2/__init__.py", line 1317, in _request
    (response, content) = self._conn_request(conn, request_uri, method, body, headers)
File "/app/httplib2/__init__.py", line 1286, in _conn_request
    response = conn.getresponse()
File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/dist27/gae_override/httplib.py", line 510, in getresponse
    'An error occured while connecting to the server: %s' % e)
error: An error occured while connecting to the server: Unable to fetch URL: http://metadata.google.internal/0.1/meta-data/service-accounts/default/acquire?scope=https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fdatastore%20https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fuserinfo.email Error: [Errno 8] nodename nor servname provided, or not known

Looks like the request to refresh the gce credentials throws a unhandled exception that breaks the code.

I comment out line 70 in helper.py and raised an exception there to temp fix it and get it to work on my dev environment.

[proppy]

Are you running googledatastore inside App Engine?

In that case you might consider to use NDB if you want to access the datastore of your application using a higher level library.

[obeleh]

Huh, is it possible to connect with python googledatastore to an App Engine devellopment server?

Edit: I would greatly appreciate the possibility!

[proppy]

@obeleh that's basically what gcd.sh is doing, see https://developers.google.com/datastore/docs/tools/devserver

[obeleh]

I don't see how that enables me to use both App Engine NDB and google cloud datastore in the same testing environment.

[proppy]

@obeleh gcd.sh wraps the Java App Engine development server, so you can't currently share data between an App Engine Python development environment and a Cloud Datastore development environment: see #21.

[obeleh]

I understand. Sorry I was just hoping I missed something and that this functionality was released.

[meredithslota]

The link above redirects to https://cloud.google.com/datastore/docs/tools/datastore-emulator now. If you are still using the Python client, I might recommend you try https://github.com/googleapis/python-datastore for additional functionality.