Android上使用grpc的方法教程

//Project的build.gradle中添加rotobuf-gradle-plugin插件buildscript { ... dependencies { ... classpath "com.google.protobuf:protobuf-gradle-plugin:0.8.0" ... } ...}

//App的build.gradle中添加下面配置apply plugin: 'com.google.protobuf'protobuf { protoc { artifact = 'com.google.protobuf:protoc:3.0.0' } plugins { javalite {  artifact = "com.google.protobuf:protoc-gen-javalite:3.0.0" } grpc {  artifact = 'io.grpc:protoc-gen-grpc-java:1.0.0' // CURRENT_GRPC_VERSION } } generateProtoTasks { all().each { task ->  task.plugins {  javalite {}  grpc {   // Options added to --grpc_out   option 'lite'  }  } } }}

//App的build.gradle中添加下面配置 dependencies { ... compile 'io.grpc:grpc-okhttp:1.1.2' compile 'io.grpc:grpc-protobuf-lite:1.1.2' compile 'io.grpc:grpc-stub:1.1.2' compile 'javax.annotation:javax.annotation-api:1.2' ...}

configurations.all { resolutionStrategy.force 'com.google.code.findbugs:jsr305:3.0.1' }

Warning:Conflict with dependency ‘com.google.code.findbugs:jsr305'. Resolved versions for app (3.0.0) and test app (2.0.1) differ. See http://g.co/androidstudio/app-test-app-conflict for details.

android { ... configurations.all { resolutionStrategy.force 'com.google.code.findbugs:jsr305:3.0.1' } ...}

public class MainActivity extends AppCompatActivity { private static final String TAG = "GrpcDemo"; private static final int PROT = 55055; private static final String NAME = "linjw"; private static final String HOST = "localhost"; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); startServer(PROT); startClient(HOST, PROT, NAME); } private void startServer(int port){ try {  Server server = ServerBuilder.forPort(port)   .addService(new GreeterImpl())   .build()   .start(); } catch (IOException e) {  e.printStackTrace();  Log.d(TAG, e.getMessage()); } } private void startClient(String host, int port, String name){ new GrpcTask(host, port, name).execute(); } private class GreeterImpl extends GreeterGrpc.GreeterImplBase { public void sayHello(HelloRequest request, StreamObserver<HelloReply> responseObserver) {  responseObserver.onNext(sayHello(request));  responseObserver.onCompleted(); } private HelloReply sayHello(HelloRequest request) {  return HelloReply.newBuilder()   .setMessage("hello "+ request.getName())   .build(); } } private class GrpcTask extends AsyncTask<Void, Void, String> { private String mHost; private String mName; private int mPort; private ManagedChannel mChannel; public GrpcTask(String host, int port, String name) {  this.mHost = host;  this.mName = name;  this.mPort = port; } @Override protected void onPreExecute() { } @Override protected String doInBackground(Void... nothing) {  try {  mChannel = ManagedChannelBuilder.forAddress(mHost, mPort)   .usePlaintext(true)   .build();  GreeterGrpc.GreeterBlockingStub stub = GreeterGrpc.newBlockingStub(mChannel);  HelloRequest message = HelloRequest.newBuilder().setName(mName).build();  HelloReply reply = stub.sayHello(message);  return reply.getMessage();  } catch (Exception e) {  StringWriter sw = new StringWriter();  PrintWriter pw = new PrintWriter(sw);  e.printStackTrace(pw);  pw.flush();  return "Failed... : " + System.lineSeparator() + sw;  } } @Override protected void onPostExecute(String result) {  try {  mChannel.shutdown().awaitTermination(1, TimeUnit.SECONDS);  } catch (InterruptedException e) {  Thread.currentThread().interrupt();  }  Log.d(TAG, result); } }}

Caused by: io.grpc.ManagedChannelProvider$ProviderNotFoundException: No functional server found. Try adding a dependency on the grpc-netty artifact

dependencies { ... compile 'io.grpc:grpc-netty:1.1.2' compile 'io.grpc:grpc-protobuf-lite:1.1.2' compile 'io.grpc:grpc-stub:1.1.2' compile 'javax.annotation:javax.annotation-api:1.2' ...}

com.android.build.api.transform.TransformException: com.android.builder.packaging.DuplicateFileException: Duplicate files copied in APK META-INF/INDEX.LIST

android { ... packagingOptions { pickFirst 'META-INF/INDEX.LIST' pickFirst 'META-INF/LICENSE' pickFirst 'META-INF/io.netty.versions.properties' } ...}

03-03 00:04:20.000 6137-6137/linjw.com.grpcdemo D/GrpcDemo: hello linjw

// Copyright 2015, Google Inc.// All rights reserved.//// Redistribution and use in source and binary forms, with or without// modification, are permitted provided that the following conditions are// met://// * Redistributions of source code must retain the above copyright// notice, this list of conditions and the following disclaimer.// * Redistributions in binary form must reproduce the above// copyright notice, this list of conditions and the following disclaimer// in the documentation and/or other materials provided with the// distribution.// * Neither the name of Google Inc. nor the names of its// contributors may be used to endorse or promote products derived from// this software without specific prior written permission.//// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.syntax = "proto3";option java_multiple_files = true;option java_package = "io.grpc.examples.helloworld";option java_outer_classname = "HelloWorldProto";option objc_class_prefix = "HLW";package helloworld;import "google/protobuf/any.proto";// The greeting service definition.service Greeter { // Sends a greeting rpc SayHello (google.protobuf.Any) returns (HelloReply) {}}// The request message containing the user's name.message HelloRequest { string name = 1;}// The response message containing the greetingsmessage HelloReply { string message = 1;}

google/protobuf/any.proto: File not found.helloworld.proto: Import “google/protobuf/any.proto” was not found or had errors.helloworld.proto:44:17: “google.protobuf.Any” is not defined.

dependencies { ... compile 'io.grpc:grpc-netty:1.1.2' compile 'io.grpc:grpc-protobuf:1.1.2' compile 'io.grpc:grpc-stub:1.1.2' compile 'javax.annotation:javax.annotation-api:1.2' ...}

protobuf { protoc {  artifact = 'com.google.protobuf:protoc:3.0.0' } plugins {  grpc {   artifact = 'io.grpc:protoc-gen-grpc-java:1.0.0' // CURRENT_GRPC_VERSION  } } generateProtoTasks {  all().each { task ->   task.builtins {    java {}   }   task.plugins {    grpc {}   }  } }}

public class MainActivity extends AppCompatActivity { private static final String TAG = "GrpcDemo"; private static final int PROT = 55055; private static final String NAME = "linjw"; private static final String HOST = "localhost"; @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);  startServer(PROT);  startClient(HOST, PROT, NAME); } private void startServer(int port){  try {   Server server = ServerBuilder.forPort(port)     .addService(new GreeterImpl())     .build()     .start();  } catch (IOException e) {   e.printStackTrace();   Log.d(TAG, e.getMessage());  } } private void startClient(String host, int port, String name){  new GrpcTask(host, port, name).execute(); } private class GreeterImpl extends GreeterGrpc.GreeterImplBase {  public void sayHello(Any request, StreamObserver<HelloReply> responseObserver) {   try {    responseObserver.onNext(sayHello(request.unpack(HelloRequest.class)));    responseObserver.onCompleted();   } catch (InvalidProtocolBufferException e) {    e.printStackTrace();   }  }  private HelloReply sayHello(HelloRequest request) {   return HelloReply.newBuilder()     .setMessage("hello "+ request.getName())     .build();  } } private class GrpcTask extends AsyncTask<Void, Void, String> {  private String mHost;  private String mName;  private int mPort;  private ManagedChannel mChannel;  public GrpcTask(String host, int port, String name) {   this.mHost = host;   this.mName = name;   this.mPort = port;  }  @Override  protected void onPreExecute() {  }  @Override  protected String doInBackground(Void... nothing) {   try {    mChannel = ManagedChannelBuilder.forAddress(mHost, mPort)      .usePlaintext(true)      .build();    GreeterGrpc.GreeterBlockingStub stub = GreeterGrpc.newBlockingStub(mChannel);    HelloRequest message = HelloRequest.newBuilder().setName(mName).build();    HelloReply reply = stub.sayHello(Any.pack(message));    return reply.getMessage();   } catch (Exception e) {    StringWriter sw = new StringWriter();    PrintWriter pw = new PrintWriter(sw);    e.printStackTrace(pw);    pw.flush();    return "Failed... : " + System.lineSeparator() + sw;   }  }  @Override  protected void onPostExecute(String result) {   try {    mChannel.shutdown().awaitTermination(1, TimeUnit.SECONDS);   } catch (InterruptedException e) {    Thread.currentThread().interrupt();   }   Log.d(TAG, result);  } }}