spring:
application:
name: local-server
gRPC有关的配置，这里只需要配置服务端口号grpc:
server:
port: 9898
- 新建拦截类LogGrpcInterceptor.java，每当gRPC请求到来后该类会先执行，这里是将方法名字在日志中打印出来，您可以对请求响应做更详细的处理：
package com.bolingcavalry.grpctutorials;
import io.grpc.metadata;
import io.grpc.ServerCall;
import io.grpc.ServerCallHandler;
import io.grpc.ServerInterceptor;
import lombok.extern.slf4j.Slf4j;
@Slf4j
public class LogGrpcInterceptor implements ServerInterceptor {
@Override
public
ServerCallHandler
log.info(serverCall.getMethodDescriptor().getFullMethodName());
return serverCallHandler.startCall(serverCall, metadata);
}
}
- 为了让LogGrpcInterceptor可以在gRPC请求到来时被执行，需要做相应的配置，如下所示，在普通的bean的配置中添加注解即可：
package com.bolingcavalry.grpctutorials;
import io.grpc.ServerInterceptor;
import net.devh.boot.grpc.server.interceptor.GrpcGlobalServerInterceptor;
import org.springframework.context.annotation.Configuration;
@Configuration(proxyBeanMethods = false)
public class GlobalInterceptorConfiguration {
@GrpcGlobalServerInterceptor
ServerInterceptor logServerInterceptor() {
return new LogGrpcInterceptor();
}
}
- 应用启动类很简单：
package com.bolingcavalry.grpctutorials;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class LocalServerApplication {
public static void main(String[] args) {
SpringApplication.run(LocalServerApplication.class, args);
}
}
- 接下来是最重要的service类，gRPC服务在此处对外暴露出去，完整代码如下，有几处要注意的地方稍后提到：
package com.bolingcavalry.grpctutorials;
import com.bolingcavalry.grpctutorials.lib.HelloReply;
import com.bolingcavalry.grpctutorials.lib.SimpleGrpc;
import net.devh.boot.grpc.server.service.GrpcService;
import java.util.Date;
@GrpcService
public class GrpcServerService extends SimpleGrpc.SimpleImplbase {
@Override
public void sayHello(com.bolingcavalry.grpctutorials.lib.HelloRequest request,
io.grpc.stub.StreamObserver
HelloReply reply = HelloReply.newBuilder().setMessage("Hello " + request.getName() + ", " + new Date()).build();
responseObserver.onNext(reply);
responseObserver.onCompleted();
}
}
- 上述GrpcServerService.java中有几处需要注意：
-
是使用@GrpcService注解，再继承SimpleImplbase，这样就可以借助grpc-server-spring-boot-starter库将sayHello暴露为gRPC服务；
-
SimpleImplbase是前文中根据proto自动生成的java代码，在grpc-lib模块中；
-
sayHello方法中处理完毕业务逻辑后，调用HelloReply.onNext方法填入返回内容；
-
调用HelloReply.onCompleted方法表示本次gRPC服务完成；
- 至此，gRPC服务端编码就完成了，咱们接着开始客户端开发；
- 在父工程grpc-turtorials下面新建名为local-client的模块，其build.gradle内容如下，注意要使用spingboot插件、依赖grpc-client-spring-boot-starter库：
plugins {
id ‘org.springframework.boot’
}
dependencies {
implementation ‘org.projectlombok:lombok’
implementation ‘org.springframework.boot:spring-boot-starter’
implementation ‘org.springframework.boot:spring-boot-starter-web’
implementation ‘net.devh:grpc-client-spring-boot-starter’
implementation project(’:grpc-lib’)
}
- 应用配置文件grpc-tutorials/local-client/src/main/resources/application.yml，注意address的值就是gRPC服务端的信息，我这里local-server和local-client在同一台电脑上运行，请您根据自己情况来设置：
server:
port: 8080
spring:
application:
name: local-grpc-client
grpc:
client:
gRPC配置的名字，GrpcClient注解会用到local-grpc-server:
gRPC服务端地址address: ‘static://127.0.0.1:9898’
enableKeepAlive: true
keepAliveWithoutCalls: true
negotiationType: plaintext
-接下来要创建下图展示的类，按序号顺序创建：
- 首先是拦截类LogGrpcInterceptor，与服务端的拦截类差不多，不过实现的接口不同：
package com.bolingcavalry.grpctutorials;
import io.grpc.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class LogGrpcInterceptor implements ClientInterceptor {
private static final Logger log = LoggerFactory.getLogger(LogGrpcInterceptor.class);
@Override
public
CallOptions callOptions, Channel next) {
log.info(method.getFullMethodName());
return next.newCal
【一线大厂Java面试题解析+后端开发学习笔记+最新架构讲解视频+实战项目源码讲义】 浏览器打开：qq.cn.hn/FTf 免费领取
l(method, callOptions);
}
}
- 为了让拦截类能够正常工作，即发起gRPC请求的时候被执行，需要新增一个配置类：
package com.bolingcavalry.grpctutorials;
import io.grpc.ClientInterceptor;
import net.devh.boot.grpc.client.interceptor.GrpcGlobalClientInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
@Order(Ordered.LOWEST_PRECEDENCE)
@Configuration(proxyBeanMethods = false)
public class GlobalClientInterceptorConfiguration {
@GrpcGlobalClientInterceptor
ClientInterceptor logClientInterceptor() {
return new LogGrpcInterceptor();
}
}
- 启动类：
package com.bolingcavalry.grpctutorials;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class LocalGrpcClientApplication {
public static void main(String[] args) {
SpringApplication.run(LocalGrpcClientApplication.class, args);
}
}
- 接下来是最重要的服务类GrpcClientService，有几处要注意的地方稍后会提到：
package com.bolingcavalry.grpctutorials;
import com.bolingcavalry.grpctutorials.lib.HelloReply;
import com.bolingcavalry.grpctutorials.lib.HelloRequest;
import com.bolingcavalry.grpctutorials.lib.SimpleGrpc;
import io.grpc.StatusRuntimeException;
import net.devh.boot.grpc.client.inject.GrpcClient;
import org.springframework.stereotype.Service;
@Service
public class GrpcClientService {
@GrpcClient(“local-grpc-server”)
private SimpleGrpc.SimpleBlockingStub simpleStub;
public String sendMessage(final String name) {
try {
final HelloReply response = this.simpleStub.sayHello(HelloRequest.newBuilder().setName(name).build());
return response.getMessage();
} catch (final StatusRuntimeException e) {
return "FAILED with " + e.getStatus().getCode().name();
}
}
}
- 上述GrpcClientService类有几处要注意的地方：
-
用@Service将GrpcClientService注册为spring的普通bean实例；
-
用@GrpcClient修饰SimpleBlockingStub，这样就可以通过grpc-client-spring-boot-starter库发起gRPC调用，被调用的服务端信息来自名为local-grpc-server的配置；
-
SimpleBlockingStub来自前文中根据helloworld.proto生成的java代码；
-
SimpleBlockingStub.sayHello方法会远程调用local-server应用的gRPC服务；
- 为了验证gRPC服务调用能否成功，再新增个web接口，接口内部会调用GrpcClientService.sendMessage，这样咱们通过浏览器就能验证gRPC服务是否调用成功了：
package com.bolingcavalry.grpctutorials;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class GrpcClientController {
@Autowired
private GrpcClientService grpcClientService;
@RequestMapping("/")
public String printMessage(@RequestParam(defaultValue = “will”) String name) {
return grpcClientService.sendMessage(name);
}
