grpcio-gcp

import os from grpc_gcp import ChannelPool from grpc_gcp.proto import api_config_pb2 import grpc # NOTE: This is a conceptual example. For a real GCP service, you would need # compiled protobufs for that service and proper API configuration. # This example assumes a 'spanner.grpc.config' file exists for demonstration. # In a real scenario, you'd replace 'spanner.grpc.config' with your actual # service configuration and define the correct stub/client. # Ensure GOOGLE_APPLICATION_CREDENTIALS is set for authentication # For local development, set this environment variable: # export GOOGLE_APPLICATION_CREDENTIALS="/path/to/your/key.json" # Or ensure gcloud is authenticated: gcloud auth application-default login # Example API configuration (replace with your service's actual config) # Content of 'spanner.grpc.config' (as mentioned in PyPI usage): # channel_pool: { # max_size: 10 # max_concurrent_streams_low_watermark: 1 # } # method: { # name: "/google.spanner.v1.Spanner/*" # per_rpc_timeout_millis: 10000 # max_retries: 3 # } if not os.environ.get('GOOGLE_APPLICATION_CREDENTIALS'): print("Warning: GOOGLE_APPLICATION_CREDENTIALS not set. Auth may fail.") try: # Load configuration from a file (example placeholder) # In a real application, you would create or load a meaningful ApiConfig api_config = api_config_pb2.ApiConfig() # Assume a config file exists for a service, e.g., 'spanner.grpc.config' # This part is illustrative; actual loading depends on your config source # For this example, we'll manually set some values for demonstration api_config.channel_pool.max_size = 5 # Create a ChannelPool instance # The target would be the address of your gRPC service, e.g., 'spanner.googleapis.com:443' target_service_address = 'localhost:50051' # Replace with actual service address with ChannelPool(target_service_address, api_config) as channel_pool: print(f"Created ChannelPool for {target_service_address}") # You can now get a channel from the pool and use it with a gRPC stub channel = channel_pool.get_channel() print(f"Obtained channel: {channel}") # Example of using the channel (requires a generated stub) # For a real service, you would import and use its generated stub: # import your_service_pb2_grpc # stub = your_service_pb2_grpc.YourServiceStub(channel) # response = stub.YourMethod(your_service_pb2.YourRequest(...)) # print(response) print("ChannelPool demonstration complete.") except Exception as e: print(f"An error occurred: {e}") print("Ensure you have a gRPC service running at the target address and correct authentication.")