Installation

gRPC-GCP Python is available wherever gRPC is available.

$ pip install grpcio-gcp

$ sudo pip install grpcio-gcp

Usage

Create a config file (e.g. spanner.grpc.config) defining API configuration, with ChannelPoolConfig and MethodConfig.

channel_pool: {
  max_size: 10
  max_concurrent_streams_low_watermark: 1
}
method: {
  name: "/google.spanner.v1.Spanner/CreateSession"
  affinity: {
    command: BIND
    affinity_key: "name"
  }
}
method: {
  name: "/google.spanner.v1.Spanner/GetSession"
  affinity: {
    command: BOUND
    affinity_key: "name"
  }
}
method: {
  name: "/google.spanner.v1.Spanner/DeleteSession"
  affinity: {
    command: UNBIND
    affinity_key: "name"
  }
}

Load configuration file to ApiConfig object.

import google.protobuf.text_format

config = grpc_gcp.api_config_from_text_pb(
    pkg_resources.resource_string(__name__, 'spanner.grpc.config'))

Create channel pool using grpc_gcp.

import grpc_gcp
import grpc

credentials = grpc.ssl_channel_credentials()
# Add api config key-value pair to options
options = [(grpc_gcp.API_CONFIG_CHANNEL_ARG, config)]
channel_pool = grpc_gcp.secure_channel(target, credentials, options)

The generated channel pool is inherited from the original grpc.Channel, with underlying support for multiple grpc channels.