---

title: gRPC Proxy keywords: [“gRPC”] description: gRPC access shenyu gateway

This document is intended to help the gRPC service access the Apache ShenYu gateway. The Apache ShenYu gateway uses the gRPC plugin to handle gRPC service.

Before the connection, start shenyu-admin correctly, start gRPC plugin, and add related dependencies on the gateway and gRPC application client. Refer to the previous Quick start with gRPC .

For details about client access configuration, see Application Client Access Config .

For details about data synchronization configurations, see Data Synchronization Config .

Add gRPC plugin in gateway

Add the following dependencies in the gateway's pom.xml file:

        <!-- apache shenyu grpc plugin start-->
        <dependency>
            <groupId>org.apache.shenyu</groupId>
            <artifactId>shenyu-spring-boot-starter-plugin-grpc</artifactId>
            <version>${project.version}</version>
        </dependency>
        <!-- apache shenyu grpc plugin end-->

• Restart the gateway service.

gRPC service access gateway

You can refer to：shenyu-examples-grpc .

1. In the microservice built by gRPC, add the following dependencies:

        <dependency>
            <groupId>org.apache.shenyu</groupId>
            <artifactId>shenyu-spring-boot-starter-client-grpc</artifactId>
            <version>${shenyu.version}</version>
            <exclusions>
                <exclusion>
                    <artifactId>guava</artifactId>
                    <groupId>com.google.guava</groupId>
                </exclusion>
            </exclusions>
        </dependency>

Execute command to generate java code in shenyu-examples-grpc project.

mvn protobuf:compile 
mvn protobuf:compile-custom 

2. Add the following configuration to application.yaml:

shenyu:
  register:
    registerType: http #zookeeper #etcd #nacos #consul
    serverLists: http://localhost:9095 #localhost:2181 #http://localhost:2379 #localhost:8848
    props:
      username: admin
      password: 123456
  client:
    grpc:
      props:
        contextPath: /grpc
        appName: grpc
        ipAndPort: 127.0.0.1:38080
        port: 38080

3. Add @ShenyuGrpcClient Annotation on the gRPC service interface implementation class. Start your service provider, after successful registration, in the background management system go to PluginList -> rpc proxy -> gRPC, you will see automatic registration of selectors and rules information.

Example:

    @Override
    @ShenyuGrpcClient(path = "/echo", desc = "echo")
    public void echo(EchoRequest request, StreamObserver<EchoResponse> responseObserver) {
        System.out.println("Received: " + request.getMessage());
        EchoResponse.Builder response = EchoResponse.newBuilder()
                .setMessage("ReceivedHELLO")
                .addTraces(Trace.newBuilder().setHost(getHostname()).build());
        responseObserver.onNext(response.build());
        responseObserver.onCompleted();
    }

User Request

You can request your gRPC service by Http. The Apache ShenYu gateway needs to have a route prefix that you access to configure contextPath.

If your proto file is defined as follows:

message EchoRequest {
  string message = 1;
}

So the request parameters look like this:

{
    "data": [
        {
            "message": "hello grpc"
        }
    ]
}

The parameters are currently passed in json format, and the name of key defaults to data, which you can reset in GrpcConstants.JSON_DESCRIPTOR_PROTO_FIELD_NAME; The value is passed in according to the proto file you define.

the Apache ShenYu can support streaming calls to gRPC service, passing multiple arguments in the form of an array.

If your proto file is defined as follows:

message RequestData {
  string text = 1;
}

The corresponding method call request parameters are as follows:

• UNARY

{
    "data": [
        {
            "text": "hello grpc"
        }
    ]
}

• CLIENT_STREAMING

{
    "data": [
        {
            "text": "hello grpc"
        }, 
        {
            "text": "hello grpc"
        }, 
        {
            "text": "hello grpc"
        }
    ]
}

• SERVER_STREAMING

{
    "data": [
        {
            "text": "hello grpc"
        }
    ]
}

• BIDI_STREAMING

{
    "data": [
        {
            "text": "hello grpc"
        }, 
        {
            "text": "hello grpc"
        }, 
        {
            "text": "hello grpc"
        }
    ]
}