grpc - 使用

GRPC - 使用

protobuf

定义protobuf，并将protobuf文件，通过java的plugin打包生成java-grpc相关文件。参照：grpc-protobuf

mvn依赖

<dependency>
            <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java-util</artifactId>
            <version>3.21.7</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-netty-shaded</artifactId>
            <version>1.30.0</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-protobuf</artifactId>
            <version>1.30.0</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-stub</artifactId>
            <version>1.30.0</version>
        </dependency>

grpc-server:

@Component
public class GrpcServer extends TestServiceGrpc.TestServiceImplBase implements InitializingBean {

    @Value("${grpc-port}")
    private int grpcPort;

    @Override
    public void searchUser(TestInfo request, StreamObserver<TestResult> responseObserver) {
        TestResult result = TestResult.newBuilder().setCode("123").setMsg("testOK").build();
        log.info(String.valueOf(request));
        responseObserver.onNext(result);
        responseObserver.onCompleted();
    }


    @Override
    public void afterPropertiesSet() throws Exception {
        grpcPort=9099;
        ServerBuilder.forPort(grpcPort)
                .addService(new GrpcServer())
                .build()
                .start();

    }
}

grpc-client:

@Component
public class GrpcClient {

        private Channel channel = channel();

        @Value("${grpcIp:127.0.0.1}")
        private String grpcIp;

        @Value("${grpcPort:9099}")
        private int grpcPort;


        public TestResult run(TestInfo testInfo) {
            TestServiceGrpc.TestBlockingStub serviceStub = TestServiceGrpc.newBlockingStub(channel);

            TestResult testResult = serviceStub.searchUser(testInfo);
            return testResult;
        }

    /**
     * Channel
     * @return
     */
    private Channel channel() {
            grpcIp="127.0.0.1";
            grpcPort=9099;
            return ManagedChannelBuilder.forAddress(grpcIp,grpcPort).usePlaintext().build();
        }

    }

Test试用

@RestController
@RequestMapping("/grpc")
public class TestGrpcController {

    @Autowired
    GrpcClient grpcClient;

    @RequestMapping("/test")
    public String grpcTest(){
        TestInfo testInfo = TestInfo.newBuilder().setCode("AAAA").build();
        TestResult testResult = grpcClient.run(testInfo);
        String json = null;
        try {
            json = JsonFormat.printer().print(testResult);
            //JsonFormat.parser().merge(json, TestInfo.newBuilder());
        } catch (InvalidProtocolBufferException e) {
            e.printStackTrace();
        }
        return json;
    }

异常

1. io.grpc.netty.shaded.io.netty.handler.ssl.NotSslRecordException: not an SSL/TLS record:

因client端采用TLS访问，而服务端默认是PlainText返回信息。

2. Request processing failed; nested exception is org.springframework.http.converter.HttpMessageConversionException: Type definition error: [simple type, class com.google.protobuf.UnknownFieldSet$Parser]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: No serializer found for class com.google.protobuf.UnknownFieldSet$Parser and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: com.yumchina.share.app.auth.hub.test.proto.AuthResult["unknownFields"]->com.google.protobuf.UnknownFieldSet["parserForType"])
因grpc产生的对象，不具备set方法，因此无法直接jackson序列化返回。需要引入protobuf-java-util工具类。