主要是体验下dart grpc 的集成试用,grpc 对于dart 的支持也是基于了插件生成代码，然后我们可以基于生成的代码创建实现，client 进行调用
参考项目
代码来自官方示例
- proto 定义
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;
// The greeting service definition.
service Greeter {
// Sends a greeting
rpc SayHello (HelloRequest) returns (HelloReply) {}
}
// The request message containing the user's name.
message HelloRequest {
string name = 1;
}
// The response message containing the greetings
message HelloReply {
string message = 1;
}
- 生成代码
注意需要安装protoc 以及 dart grpc 扩展dart pub global activate protoc_plugin
protoc --dart_out=grpc:lib/src/generated -Iprotos protos/helloworld.proto
- 效果
- server 实现
server.dart
import 'package:grpc/grpc.dart';
import 'package:helloworld/src/generated/helloworld.pbgrpc.dart';
// 实现
class GreeterService extends GreeterServiceBase {
@override
Future<HelloReply> sayHello(ServiceCall call, HelloRequest request) async {
return HelloReply()..message = 'Hello, ${request.name}!';
}
}
// 服务启动
Future<void> main(List<String> args) async {
final server = Server.create(
services: [GreeterService()],
codecRegistry: CodecRegistry(codecs: const [GzipCodec(), IdentityCodec()]),
);
await server.serve(port: 50051);
print('Server listening on port ${server.port}...');
}
- client 实现
client.dart
import 'package:grpc/grpc.dart';
import 'package:helloworld/src/generated/helloworld.pbgrpc.dart';
Future<void> main(List<String> args) async {
// channel 创建
final channel = ClientChannel(
'localhost',
port: 50051,
options: ChannelOptions(
credentials: ChannelCredentials.insecure(),
codecRegistry:
CodecRegistry(codecs: const [GzipCodec(), IdentityCodec()]),
),
);
// client stub
final stub = GreeterClient(channel);
final name = args.isNotEmpty ? args[0] : 'world';
try {
final response = await stub.sayHello(
HelloRequest()..name = name,
options: CallOptions(compression: const GzipCodec()),
);
print('Greeter client received: ${response.message}');
} catch (e) {
print('Caught error: $e');
}
await channel.shutdown();
}
说明
对于一些业务系统（比如基于flutter 开发的桌面应用基于dart grpc 进行数据通信也是一个不错的选择），当然buf 基于protobuf 的connect
协议也是一个不错的选择
参考资料
https://connectrpc.com/
https://github.com/grpc/grpc-dart
https://pub.dev/packages/grpc/install
https://buf.build/
https://grpc.io/docs/languages/dart/quickstart/
https://github.com/grpc/grpc-web