Class GrpcTransportConfig

java.lang.Object
org.a2aproject.sdk.client.transport.spi.ClientTransportConfig<GrpcTransport>
org.a2aproject.sdk.client.transport.grpc.GrpcTransportConfig
public class GrpcTransportConfig extends ClientTransportConfig<GrpcTransport>
Configuration for the gRPC transport protocol.

This configuration class allows customization of the gRPC channel factory used for communication with A2A agents. Unlike other transports, gRPC requires a channel factory to be explicitly provided - there is no default implementation.

Channel Factory Requirement: You must provide a Function<String, Channel> that creates gRPC channels from agent URLs. This gives you full control over channel configuration including connection pooling, TLS, load balancing, and interceptors.

Basic usage with ManagedChannel: 

// Simple insecure channel for development
Function<String, Channel> channelFactory = url -> {
    String target = extractTarget(url); // e.g., "localhost:9999"
    return ManagedChannelBuilder.forTarget(target)
        .usePlaintext()
        .build();
};

GrpcTransportConfig config = new GrpcTransportConfigBuilder()
    .channelFactory(channelFactory)
    .build();

Client client = Client.builder(agentCard)
    .withTransport(GrpcTransport.class, config)
    .build();

Production configuration with TLS and timeouts: 

Function<String, Channel> channelFactory = url -> {
    String target = extractTarget(url);
    return ManagedChannelBuilder.forTarget(target)
        .useTransportSecurity()
        .keepAliveTime(30, TimeUnit.SECONDS)
        .idleTimeout(5, TimeUnit.MINUTES)
        .maxInboundMessageSize(10 * 1024 * 1024) // 10MB
        .build();
};

GrpcTransportConfig config = new GrpcTransportConfigBuilder()
    .channelFactory(channelFactory)
    .build();

With load balancing and connection pooling: 

Function<String, Channel> channelFactory = url -> {
    String target = extractTarget(url);
    return ManagedChannelBuilder.forTarget(target)
        .defaultLoadBalancingPolicy("round_robin")
        .maxInboundMessageSize(50 * 1024 * 1024)
        .keepAliveTime(30, TimeUnit.SECONDS)
        .keepAliveTimeout(10, TimeUnit.SECONDS)
        .build();
};

With interceptors: 

GrpcTransportConfig config = new GrpcTransportConfigBuilder()
    .channelFactory(channelFactory)
    .addInterceptor(new LoggingInterceptor())
    .addInterceptor(new AuthInterceptor(apiKey))
    .build();

Channel Lifecycle: The channel factory creates channels on-demand when the client connects to an agent. You are responsible for shutting down channels when the client is closed. Consider using ManagedChannel.shutdown() in a cleanup hook.

See Also:

  • Constructor Details

    • GrpcTransportConfig

      public GrpcTransportConfig(Function<String, io.grpc.Channel> channelFactory)
      Create a gRPC transport configuration with a custom channel factory.

      Consider using GrpcTransportConfigBuilder instead for a more fluent API.

      Parameters:
      channelFactory - function to create gRPC channels from agent URLs (must not be null)
      Throws:
      IllegalArgumentException - if channelFactory is null

  • Method Details

    • getChannelFactory

      public Function<String, io.grpc.Channel> getChannelFactory()
      Get the configured channel factory.
      Returns:
      the channel factory function