credentials file is unusable with prediction API

[crazystick]

Using a credentials file when building a client for the prediction API fails. See the code sample below. From looking at the code, when initialising the PredictionServiceGrpcTransport class, the parent constructor in PredictionServiceTransport is called. The base constructor creates the credentials from the file (base.py, line 102). These credentials are then passed into the create_channel function (grpc.py, line 162) along with the credentials file, which eventually leads to the DuplicateCredentialArgs error.

Environment details

• OS type and version: Linux xxx 5.16.1-arch1-1 #1 SMP PREEMPT Sun, 16 Jan 2022 11:39:23 +0000 x86_64 GNU/Linux
• Python version: Python 3.10.1
• pip version: pip 20.3.4
• google-cloud-aiplatform version: Version: 1.9.0

Code example

from google.cloud import aiplatform
from google.api_core.client_options import ClientOptions


def main():

    api_endpoint = "us-central1-aiplatform.googleapis.com"

    # The AI Platform services require regional API endpoints.
    client_options = ClientOptions(api_endpoint=api_endpoint, credentials_file='google_key.json')

    # Initialize client that will be used to create and send requests.
    client = aiplatform.gapic.PredictionServiceClient(client_options=client_options)


if __name__ == "__main__":
    main()

Stack trace

Traceback (most recent call last):
  File "./credentials_bug.py", line 19, in <module>
    main()
  File "./credentials_bug.py", line 15, in main
    client = aiplatform.gapic.PredictionServiceClient(client_options=client_options)
  File "./venv/lib/python3.10/site-packages/google/cloud/aiplatform_v1/services/prediction_service/client.py", line 371, in __init__
    self._transport = Transport(
  File "./venv/lib/python3.10/site-packages/google/cloud/aiplatform_v1/services/prediction_service/transports/grpc.py", line 160, in __init__
    self._grpc_channel = type(self).create_channel(
  File "./venv/lib/python3.10/site-packages/google/cloud/aiplatform_v1/services/prediction_service/transports/grpc.py", line 212, in create_channel
    return grpc_helpers.create_channel(
  File "./venv/lib/python3.10/site-packages/google/api_core/grpc_helpers.py", line 302, in create_channel
    composite_credentials = _create_composite_credentials(
  File "./venv/lib/python3.10/site-packages/google/api_core/grpc_helpers.py", line 223, in _create_composite_credentials
    raise exceptions.DuplicateCredentialArgs(
google.api_core.exceptions.DuplicateCredentialArgs: 'credentials' and 'credentials_file' are mutually exclusive.

[parthea]

Hi @crazystick,

Thanks for reporting this issue and providing a code snippet. I was able to reproduce the issue locally. This part of this library appears to be autogenerated and I can reproduce the same issue in other googleapis python libraries. I've filed a bug with the upstream team here: googleapis/gapic-generator-python#1152 .

[busunkim96]

@parthea Thanks for fixing the generator! Are there any blockers to getting the owlbot update through?

[parthea]

The fix was already merged in #990.

[parthea]

I'll keep this issue open until #951 is merged

[parthea]

I've bumped the priority down to p2 as the fix has been merged. We're just waiting for the next release.