java --gRPC实践

java --gRPC实践 1.新建springboot项目 2.pom.xml中配置

    4.0.0
    
        org.springframework.boot
        spring-boot-starter-parent
        2.6.1
         
    
    com.example
    demo
    0.0.1-SNAPSHOT
    demo
    Demo project for Spring Boot
    
        1.8
    
    
        
            org.springframework.boot
            spring-boot-starter-web
        
        
            org.springframework.boot
            spring-boot-starter-test
            test
        
        
            com.google.protobuf
            protobuf-java
            3.5.1
        
        
            io.grpc
            grpc-all
            1.12.0
        
    
    
        
            
                kr.motd.maven
                os-maven-plugin
                1.4.1.Final
            
        
        
            
                org.xolstice.maven.plugins
                protobuf-maven-plugin
                0.5.0
                
                    com.google.protobuf:protoc:3.0.0:exe:${os.detected.classifier}
                    grpc-java
                    io.grpc:protoc-gen-grpc-java:1.0.0:exe:${os.detected.classifier}
                
                
                    
                        
                            compile
                            compile-custom
                        
                    
                
            
            
            
            
            
        
    

3.安装插件：Protobuf Support

4.在main文件夹下创建proto文件夹。注意：proto文件夹和java文件夹在同一目录 

syntax = "proto3";

option java_multiple_files = true;
option java_package = "io.grpc.justtest";
option java_outer_classname = "JustTestProto";
option objc_class_prefix = "WY";

package onlytest;

//定义服务
service Greeter {
  //注意：这里是returns 不是return
  rpc TestSomeThing (TestRequest) returns (TestResponse) {
  }
}
//定义消息类型
message TestRequest {
  string name = 1;
}
message TestResponse {
  string message = 1;
}

5.执行maven中install，在target文件夹下generated-sources中生成GreeterGrpc等一系列文件

6.服务端代码

package com.example.test;

import io.grpc.Server;
import io.grpc.ServerBuilder;
import io.grpc.justtest.GreeterGrpc;
import io.grpc.justtest.TestRequest;
import io.grpc.justtest.TestResponse;
import io.grpc.stub.StreamObserver;

import java.io.IOException;


public class TestServer {
    //定义端口
    private final int port = 50051;
    //服务
    private Server server;

    //启动服务,并且接受请求
    private void start() throws IOException {
        server = ServerBuilder.forPort(port).addService(new GreeterImpl()).build().start();
        System.out.println("服务开始启动-------");
        Runtime.getRuntime().addShutdownHook(new Thread() {
            @Override
            public void run() {
                System.err.println("------shutting down gRPC server since JVM is shutting down-------");
                TestServer.this.stop();
                System.err.println("------server shut down------");
            }
        });
    }

    //stop服务
    private void stop() {
        if (server != null) {
            server.shutdown();
        }
    }
    //server阻塞到程序退出
    private void  blockUntilShutdown() throws InterruptedException {
        if (server!=null){
            server.awaitTermination();
        }
    }

    //实现服务接口的类
    private class GreeterImpl extends GreeterGrpc.GreeterImplbase {
        @Override
        public void testSomeThing(TestRequest request, StreamObserver responseObserver) {
            TestResponse build = TestResponse.newBuilder().setMessage(request.getName()).build();
            //onNext()方法向客户端返回结果
            responseObserver.onNext(build);
            //告诉客户端这次调用已经完成
            responseObserver.onCompleted();
        }
    }

    public static void main(String[] args) throws IOException, InterruptedException {
        final  TestServer server=new TestServer();
        server.start();
        server.blockUntilShutdown();
    }
}

7.客户端代码 

package com.example.test;
import io.grpc.ManagedChannel;
import io.grpc.ManagedChannelBuilder;
import io.grpc.justtest.GreeterGrpc;
import io.grpc.justtest.TestRequest;
import io.grpc.justtest.TestResponse;

import java.util.concurrent.TimeUnit;

public class TestClient {
    private final ManagedChannel channel;
    private final GreeterGrpc.GreeterBlockingStub blockingStub;
    private static final String host="127.0.0.1";
    private static final int ip=50051;
    public TestClient(String host,int port){
        //usePlaintext表示明文传输，否则需要配置ssl
        //channel  表示通信通道
        channel= ManagedChannelBuilder.forAddress(host, port).usePlaintext(true).build();
        //存根
        blockingStub=GreeterGrpc.newBlockingStub(channel);
    }
    public void shutdown() throws InterruptedException {
        channel.shutdown().awaitTermination(5, TimeUnit.SECONDS);
    }
    public void  testResult(String name){
        TestRequest request=TestRequest.newBuilder().setName(name).build();
        TestResponse response=blockingStub.testSomeThing(request);
        System.out.println(response.getMessage());
    }
    public static void main(String[] args) {
        TestClient client=new TestClient(host,ip);
        for (int i=0;i<=5;i++){
            client.testResult("<<<<>>>>:"+i);
        }
    }
}

8.启动测试：先启动服务，后启动客户端