springcloud集成grpc（一） - HelloWorld开发者社区

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GRPC简介

是谷歌开源的一个高性能的、通用的RPC框架。和其他RPC一样，客户端应用程序可以直接调用远程服务的方法，就好像调用本地方法一样。它隐藏了底层的实现细节，包括序列化（XML、JSON、二进制）、数据传输（TCP、HTTP、UDP）、反序列化等，开发人员只需要关自业务本身，而不需要关注RPC的技术细节。

与其他RPC框架一样，gRPC也遵循定义服务(类似于定义接口的思想)。gRPC客户端通过定义方法名、方法参数和返回类型来声明一个可以被远程调用的接口方法。由服务端实现客户端定义的接口方法，并运行一个gRPC服务来处理gPRC 客户端调用。注意，gRPC客户端和服务端共用一个接口方法。

springcloud与grpc

springcloud使用restful api进行内部通信，使用的是http1，而grpc使用http2来作为通信协议

至于http2的优势就不说了，对于很多电商服务内部调用链很复杂，使用grpc能有效的缩短通信时长。

springboot2集成net.devh.grpc

这里序列化框架使用protobuf

grpc-server

1、增加依赖

<dependency>
    <groupId>io.protostuff</groupId>
    <artifactId>protostuff-core</artifactId>
    <version>1.6.0</version>
</dependency>

<dependency>
    <groupId>io.protostuff</groupId>
    <artifactId>protostuff-runtime</artifactId>
    <version>1.6.0</version>
</dependency>
<dependency>
    <groupId>io.grpc</groupId>
    <artifactId>grpc-all</artifactId>
    <version>${grpc.version}</version>
</dependency>
<!-- Spring Boot 配置处理 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
</dependency>

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>
<dependency>
    <groupId>net.devh</groupId>
    <artifactId>grpc-server-spring-boot-starter</artifactId>
</dependency>

2、增加protobuf配置文件

在src/main/proto下增加配置文件hello.proto

syntax = "proto3";
package com.demo;
option java_package = "com.demo";


message HelloRequest {
    string name = 1;
}

message HelloResponse {
    string name = 1;
    string status = 1;
}

// rpc 服务
service HelloService {
    rpc hello(HelloRequest) returns(HelloResponse) {}
}

3、通过proto自动生成java代码并增加grpcservice

@GrpcService
public class HelloGrpcService extends HelloServiceGrpc.HelloServiceImplBase {
    private static Logger logger = LoggerFactory.getLogger(UserProfileGrpcService.class);

    @Override
    public void hello(Hello.HelloRequest request, StreamObserver<Hello.HelloResponse> responseObserver) {
        logger.info("hello start");
        final Hello.HelloResponse.Builder replyBuilder = Hello.HelloResponse.newBuilder().setName(request.getName()).setStatus("success");
        responseObserver.onNext(replyBuilder.build());
        responseObserver.onCompleted();
    }
}

4、增加启动类

@EnableDiscoveryClient
public class GrpcServerApplication {

    public static void main(String[] args) {
        SpringApplication.run(GrpcServerApplication.class, args);
    }

}

5、增加yml配置

server:
  port: 8011
grpc:
  server:
    port: 6000
spring:
  application:
    name: hello-grpc-server

grpc-client

1、依赖包

<dependency>
    <groupId>io.protostuff</groupId>
    <artifactId>protostuff-core</artifactId>
    <version>1.6.0</version>
</dependency>

<dependency>
    <groupId>io.protostuff</groupId>
    <artifactId>protostuff-runtime</artifactId>
    <version>1.6.0</version>
</dependency>
<dependency>
    <groupId>io.grpc</groupId>
    <artifactId>grpc-all</artifactId>
    <version>${grpc.version}</version>
</dependency>
<!-- Spring Boot 配置处理 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
</dependency>
<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>
<dependency>
    <groupId>net.devh</groupId>
    <artifactId>grpc-client-spring-boot-starter</artifactId>
</dependency>

2、增加调用service

@Service
public class GrpcClientService {

    @GrpcClient("hello-grpc-server")
    private Channel serverChannel;

    public String hello(String name) {
        HelloServiceGrpc.HelloServiceBlockingStub stub = HelloServiceGrpc.newBlockingStub(serverChannel);
        Hello.HelloRequest.Builder builder= Hello.HelloRequest.newBuilder().
                setName("xiaoli");
        Hello.HelloResponse response = stub.hello(builder.build());
        return "{'responseStatus':'"+response.getStatus()+"','result':[]}";
    
    }
}

其中这里已经增加了负载均衡，grpc官网推荐的负载均衡方案就是在应用层管理http2长连接池。

增加controller

@RestController
@RequestMapping("/test")
public class HelloController {
    private static Logger logger = LoggerFactory.getLogger(HelloController.class);
    @Autowired
    private GrpcClientService grpcClientService;

    @RequestMapping(value = "/hello", method = RequestMethod.GET)
    public String hello() {
        try {
            String result = grpcClientService.hello(“aa”);
            logger.debug(" respString : {}",result);
            return result;
        } catch (Throwable e) {
            logger.error("hello error", e);
        }
        return null;
    }

增加yml配置

info:
  version: 1.0
  name: hello-grpc-client


server:
  port: 8012
      
grpc:
  client:
    hello-grpc-server:
      enableKeepAlive: true
      keepAliveWithoutCalls: true
      negotiationType: plaintext

启动服务可以访问http://localhost:8012/test/hello?进行测试