gRPC Java、Go、PHP使用例子

本文例子是在Window平台测试，Java编写的gRPC服务器端，同时使用Java、Go、PHP编写客户端调用。

1、Protocol Buffers定义接口

1.1、编写接口服务

// 定义protocol buffers版本(proto3)
syntax = "proto3";// 定义包名，避免协议消息类型之间的命名冲突。
package helloworld;// 定义java格式
option java_multiple_files = true;
option java_package = "com.penngo.grpc";
option java_outer_classname = "HelloWorldProto";
option objc_class_prefix = "HLW";// 服务接口定义
service Greeter { // 方法1定义rpc SayHello (HelloRequest) returns (HelloReply) {}// 方法2定义rpc SayHelloAgain (HelloRequest) returns (HelloReply) {}
}// HelloRequest消息类型格式定义，
message HelloRequest {// name为定义字段名，1为消息传输中的字段编号，使用后，不应该改编号。string name = 1;
}// HelloReply消息类型格式定义，
message HelloReply {// message为定义字段名，1为消息传输中的字段编号，使用后，不应该改编号。string message = 1;
}

1.2、Protobuf基础数据类型

    <th>C++</th><th>Java/Kotlin</th><th>Python</th><th>Go</th><th>Ruby</th><th>C#</th><th>PHP</th><th>Dart</th>
</tr>
<tr><td>double</td><td>double</td><td>double</td><td>float</td><td>float64</td><td>Float</td><td>double</td><td>float</td><td>double</td>
</tr>
<tr><td>float</td><td>float</td><td>float</td><td>float</td><td>float32</td><td>Float</td><td>float</td><td>float</td><td>double</td>
</tr>
<tr><td>int32</td><td>int32</td><td>int</td><td>int</td><td>int32</td><td>Fixnum or Bignum (as required)</td><td>int</td><td>integer</td><td>int</td>
</tr>
<tr><td>int64</td><td>int64</td><td>long</td><td>int/long<sup>[4]</sup></td><td>int64</td><td>Bignum</td><td>long</td><td>integer/string<sup>[6]</sup></td><td>Int64</td>
</tr>
<tr><td>uint32</td><td>uint32</td><td>int<sup>[2]</sup></td><td>int/long<sup>[4]</sup></td><td>uint32</td><td>Fixnum or Bignum (as required)</td><td>uint</td><td>integer</td><td>int</td>
</tr>
<tr><td>uint64</td><td>uint64</td><td>long<sup>[2]</sup></td><td>int/long<sup>[4]</sup></td><td>uint64</td><td>Bignum</td><td>ulong</td><td>integer/string<sup>[6]</sup></td><td>Int64</td>
</tr>
<tr><td>sint32</td><td>int32</td><td>int</td><td>int</td><td>int32</td><td>Fixnum or Bignum (as required)</td><td>int</td><td>integer</td><td>int</td>
</tr>
<tr><td>sint64</td><td>int64</td><td>long</td><td>int/long<sup>[4]</sup></td><td>int64</td><td>Bignum</td><td>long</td><td>integer/string<sup>[6]</sup></td><td>Int64</td>
</tr>
<tr><td>fixed32</td><td>uint32</td><td>int<sup>[2]</sup></td><td>int/long<sup>[4]</sup></td><td>uint32</td><td>Fixnum or Bignum (as required)</td><td>uint</td><td>integer</td><td>int</td>
</tr>
<tr><td>fixed64</td><td>uint64</td><td>long<sup>[2]</sup></td><td>int/long<sup>[4]</sup></td><td>uint64</td><td>Bignum</td><td>ulong</td><td>integer/string<sup>[6]</sup></td><td>Int64</td>
</tr>
<tr><td>sfixed32</td><td>int32</td><td>int</td><td>int</td><td>int32</td><td>Fixnum or Bignum (as required)</td><td>int</td><td>integer</td><td>int</td>
</tr>
<tr><td>sfixed64</td><td>int64</td><td>long</td><td>int/long<sup>[4]</sup></td><td>int64</td><td>Bignum</td><td>long</td><td>integer/string<sup>[6]</sup></td><td>Int64</td>
</tr>
<tr><td>bool</td><td>bool</td><td>boolean</td><td>bool</td><td>bool</td><td>TrueClass/FalseClass</td><td>bool</td><td>boolean</td><td>bool</td>
</tr>
<tr><td>string</td><td>string</td><td>String</td><td>str/unicode<sup>[5]</sup></td><td>string</td><td>String (UTF-8)</td><td>string</td><td>string</td><td>String</td>
</tr>
<tr><td>bytes</td><td>string</td><td>ByteString</td><td>str (Python 2)<br>bytes (Python 3)</td><td>[]byte</td><td>String (ASCII-8BIT)</td><td>ByteString</td><td>string</td><td>List<int></int></td>
</tr>
</tbody>

.proto

https://protobuf.dev/programming-guides/proto3/

2、服务器端实现

服务器端实例使用java编写

2.1、生成gRPC服务类

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>com.penngo</groupId><artifactId>grpc-helloworld</artifactId><version>1.0</version><properties><maven.compiler.source>11</maven.compiler.source><maven.compiler.target>11</maven.compiler.target><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies><dependency><groupId>io.grpc</groupId><artifactId>grpc-netty-shaded</artifactId><version>1.59.0</version><scope>runtime</scope></dependency><dependency><groupId>io.grpc</groupId><artifactId>grpc-protobuf</artifactId><version>1.59.0</version></dependency><dependency><groupId>io.grpc</groupId><artifactId>grpc-stub</artifactId><version>1.59.0</version></dependency><dependency> <!-- necessary for Java 9+ --><groupId>org.apache.tomcat</groupId><artifactId>annotations-api</artifactId><version>6.0.53</version><scope>provided</scope></dependency></dependencies><build><extensions><extension><groupId>kr.motd.maven</groupId><artifactId>os-maven-plugin</artifactId><version>1.7.1</version></extension></extensions><plugins><!-- grpc代码生成插件 --><plugin><groupId>org.xolstice.maven.plugins</groupId><artifactId>protobuf-maven-plugin</artifactId><version>0.6.1</version><configuration><protocArtifact>com.google.protobuf:protoc:3.24.0:exe:${os.detected.classifier}</protocArtifact><pluginId>grpc-java</pluginId><pluginArtifact>io.grpc:protoc-gen-grpc-java:1.59.0:exe:${os.detected.classifier}</pluginArtifact></configuration><executions><execution><goals><goal>compile</goal><goal>compile-custom</goal></goals></execution></executions></plugin></plugins></build><repositories><repository><id>alimaven</id><name>Maven Aliyun Mirror</name><url>https://maven.aliyun.com/repository/central</url></repository></repositories><pluginRepositories><pluginRepository><id>public</id><name>aliyun nexus</name><url>https://maven.aliyun.com/nexus/content/groups/public/</url><releases><enabled>true</enabled></releases><snapshots><enabled>false</enabled></snapshots></pluginRepository></pluginRepositories>
</project>

命令行下执行gRPC的java代码

mvn compile

自动扫描代码目中src/main/proto/helloworld.proto下的proto文件，自动生成gRPC相关代码到target/generated-sources/protobuf目录下。

2.2、Java服务器端实现

HelloServer.java

package com.penngo;import com.penngo.grpc.GreeterGrpc;
import com.penngo.grpc.HelloReply;
import com.penngo.grpc.HelloRequest;
import io.grpc.Grpc;
import io.grpc.InsecureServerCredentials;
import io.grpc.Server;
import io.grpc.stub.StreamObserver;
import java.io.IOException;public class HelloServer {public static void main(String[] args) throws IOException, InterruptedException {int port = 50051;Server server = Grpc.newServerBuilderForPort(port, InsecureServerCredentials.create()).addService(new GreeterImpl()).build().start();Runtime.getRuntime().addShutdownHook(new Thread(()->{System.err.println("*** shutting down gRPC server since JVM is shutting down");stopServer(server);System.err.println("*** server shut down");}));server.awaitTermination();}private static void stopServer(Server server) {if (server != null) {server.shutdown();}}static class GreeterImpl extends GreeterGrpc.GreeterImplBase {@Overridepublic void sayHello(HelloRequest req, StreamObserver<HelloReply> responseObserver) {System.out.println("收到客户端消息：" + req.getName());String msg = "我是Java Server";System.out.println("回复客户端消息：" + msg);HelloReply reply = HelloReply.newBuilder().setMessage("你好！" + msg).build();responseObserver.onNext(reply);responseObserver.onCompleted();}@Overridepublic void sayHelloAgain(HelloRequest req, StreamObserver<HelloReply> responseObserver) {System.out.println("再次收到客户端消息：" + req.getName());String msg = "我是Java Server2";System.out.println("再次回复客户端消息：" + msg);HelloReply reply = HelloReply.newBuilder().setMessage(msg).build();responseObserver.onNext(reply);responseObserver.onCompleted();}}
}

https://github.com/protocolbuffers/protobuf/releases

3、java、go、php客户端实现

3.1、Java客户端实现

HelloClient.java

package com.penngo;import com.penngo.grpc.GreeterGrpc;
import com.penngo.grpc.HelloReply;
import com.penngo.grpc.HelloRequest;
import io.grpc.Grpc;
import io.grpc.InsecureChannelCredentials;
import io.grpc.ManagedChannel;import java.util.concurrent.TimeUnit;public class HelloClient {public static void main(String[] args) throws InterruptedException {String host = "localhost";int port = 50051;ManagedChannel managedChannel = Grpc.newChannelBuilderForAddress(host, port, InsecureChannelCredentials.create()).build();GreeterGrpc.GreeterBlockingStub blockingStub = GreeterGrpc.newBlockingStub(managedChannel);String msg1 = "我是java client";System.out.println("向服务器端发送消息：" + msg1);HelloRequest helloRequest1 = HelloRequest.newBuilder().setName(msg1).build();HelloReply reply1 = blockingStub.sayHello(helloRequest1);System.out.println("收到服务器端消息：" + reply1.getMessage());String msg2 = "我是java client2";System.out.println("再次向服务器端发送消息：" + msg2);HelloRequest helloRequest2 = HelloRequest.newBuilder().setName(msg2).build();HelloReply reply2 = blockingStub.sayHelloAgain(helloRequest2);System.out.println("再次收到服务器端消息：" + reply2.getMessage());managedChannel.shutdownNow().awaitTermination(5, TimeUnit.SECONDS);}}

3.2、Go客户端实现

Go的代码生成需要使用protoc.exe来编译helloworld.proto服务文件，生成对应的服务调用代码
下载地址：https://github.com/protocolbuffers/protobuf/releases，当前最新版本为protoc-25.1-win64.zip
解压到目录D:\Program Files\protoc-25.1-win64\bin，需要把这个目录添加到环境变量PATH当中。

安装protocol编译器的Go插件

$ go install google.golang.org/protobuf/cmd/protoc-gen-go@v1.28
$ go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@v1.2

执行下边命令生成Go的gRPC代码

protoc --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative helloworld/helloworld.proto

编写客户端实现代码

package mainimport ("context""flag""google.golang.org/grpc""google.golang.org/grpc/credentials/insecure"pb "grpctest/helloworld""log""time"
)var (addr = flag.String("addr", "localhost:50051", "the address to connect to")
)func main() {flag.Parse()// Set up a connection to the server.conn, err := grpc.Dial(*addr, grpc.WithTransportCredentials(insecure.NewCredentials()))if err != nil {log.Fatalf("did not connect: %v", err)}defer conn.Close()c := pb.NewGreeterClient(conn)// Contact the server and print out its response.ctx, cancel := context.WithTimeout(context.Background(), time.Second)defer cancel()msg1 := "我是go client"log.Printf("向服务器端发送消息: %s", msg1)r1, err1 := c.SayHello(ctx, &pb.HelloRequest{Name: msg1})if err1 != nil {log.Fatalf("could not greet: %v", err1)}log.Printf("收到服务器端消息：%s", r1.GetMessage())msg2 := "我是go client2"log.Printf("再次向服务器端发送消息: %s", msg1)r2, err2 := c.SayHelloAgain(ctx, &pb.HelloRequest{Name: msg2})if err2 != nil {log.Fatalf("could not greet: %v", err2)}log.Printf("再次收到服务器端消息: %s", r2.GetMessage())
}

3.3、PHP客户端实现

安装gRPC的PHP扩展https://pecl.php.net/package/gRPC
当前测试php版本7.3，下载php_grpc-1.42.0-7.3-nts-vc15-x64.zip
php.ini这个文件加入

extension=php_grpc.dll

新建composer.json

{"name": "xxs/grpc","require": {"grpc/grpc": "^v1.4.0","google/protobuf": "^v3.3.0"},"autoload":{"psr-4":{"GPBMetadata\\":"GPBMetadata/","Helloworld\\":"Helloworld/"}}
}

在composer.json相同目录下执行命令下载依赖库

composer install

安装grpc的php插件，https://github.com/lifenglsf/grpc_for_windows
解压复制到项目下grpc_for_windows/x64/grpc_php_plugin.exe

执行命令生成gRPC代码

protoc --proto_path=. --php_out=. --grpc_out=. --plugin=protoc-gen-grpc=grpc_for_windows/x64/grpc_php_plugin.exe ./helloworld.proto

client.php实现

<?php
require dirname(__FILE__) . '/vendor/autoload.php';
//echo dirname(__FILE__) . '/vendor/autoload.php';
function greet($hostname)
{$client = new Helloworld\GreeterClient($hostname, ['credentials' => Grpc\ChannelCredentials::createInsecure(),]);$request = new Helloworld\HelloRequest();$msg1 = "我是PHP client";$request->setName($msg1);echo "向服务器端发送消息: $msg1". PHP_EOL;list($response, $status) = $client->SayHello($request)->wait();if ($status->code !== Grpc\STATUS_OK) {echo "ERROR: " . $status->code . ", " . $status->details . PHP_EOL;exit(1);}echo "收到服务器端消息：".$response->getMessage() . PHP_EOL;$msg2 = "我是PHP client2";$request->setName($msg2);echo "再次向服务器端发送消息: $msg2". PHP_EOL;list($response, $status) = $client->SayHelloAgain($request)->wait();if ($status->code !== Grpc\STATUS_OK) {echo "ERROR: " . $status->code . ", " . $status->details . PHP_EOL;exit(1);}echo "再次收到服务器端发送消息：".$response->getMessage() . PHP_EOL;$client->close();
}$hostname = !empty($argv[2]) ? $argv[2] : 'localhost:50051';
greet($hostname);

附件源码