自动化设备东莞网站建设,电商网站商品页的优化目标是什么?,网站域名做哪个会计科目,百度云建站教程测试gRPC例子 编写proto文件实现服务端代码实现客户端代码 通过gRPC 已经编译并且安装好之后#xff0c;就可以在源码目录下找到example 文件夹下来试用gRPC 提供的例子。
在这里我使用VS2022来打开仓库目录下example/cpp/helloworld目录
编写proto文件
下面是我改写的exa… 测试gRPC例子 编写proto文件实现服务端代码实现客户端代码 通过gRPC 已经编译并且安装好之后就可以在源码目录下找到example 文件夹下来试用gRPC 提供的例子。
在这里我使用VS2022来打开仓库目录下example/cpp/helloworld目录
编写proto文件
下面是我改写的example/protos/helloworld.proto 和相应的greeter_client.cc 和 greeter_server.cc两个文件。这里面定义了一个叫做Greeter的服务同时这里尝试4种类型的方法。
简单 RPC 客户端使用存根发送请求到服务器并等待响应返回就像平常的函数调用一样。服务器端流式 RPC 客户端发送请求到服务器拿到一个流去读取返回的消息序列。 客户端读取返回的流直到里面没有任何消息。从例子中可以看出通过在响应类型前插入 stream 关键字可以指定一个服务器端的流方法。客户端流式 RPC 客户端写入一个消息序列并将其发送到服务器同样也是使用流。一旦客户端完成写入消息它等待服务器完成读取返回它的响应。通过在请求类型前指定 stream 关键字来指定一个客户端的流方法。双向流式 RPC双方使用读写流去发送一个消息序列。两个流独立操作因此客户端和服务器可以以任意喜欢的顺序读写比如服务器可以在写入响应前等待接收所有的客户端消息或者可以交替的读取和写入消息或者其他读写的组合。 每个流中的消息顺序被预留。你可以通过在请求和响应前加 stream 关键字去制定方法的类型。
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 {// A simple RPC rpc SayHello (HelloRequest) returns (HelloReply) {}// A server-side streaming RPCrpc SayHelloStreamReply (HelloRequest) returns (stream HelloReply) {}// A client-side streaming RPC rpc StreamHelloReply (stream HelloRequest) returns (HelloReply) {}// A bidirectional streaming RPCrpc StreamHelloStreamReply (stream HelloRequest) returns (stream HelloReply) {}
}// The request message containing the users name.
message HelloRequest {string name 1;
}// The response message containing the greetings
message HelloReply {string message 1;
}当编辑完helloworld.proto文件之后可以直接点击vs2022-生成-全部重新生成。此时VS会调用protocol buffer 编译器和gRPC C plugin生成4个客户端和服务端的文件所有生成的文件在${projectDir}\out\build\${name}文件夹下。
如下方是我编写的手动生成这4个文件的批处理脚本
echo offset fileNametemp
set currentPath%~dp0%
set target--cpp_out
set protocPath Your protoc path
set pluginPath Your c plugin pathfor %%I in (%*) do (for /f tokens1,2 delims-/: %%J in (%%I%) do (if %%Jf (set fileName%%K)if %%Jt (set target%%K))
)if not exist %currentPath%%fileName% (echo file not existgoto:error
)
if %target%python (set pluginPath Your python plugin pathset target--python_out
)
if %target%csharp (set pluginPath Your C# plugin pathset target--csharp_out
)%protocPath% --grpc_out%currentPath% --pluginprotoc-gen-grpc%pluginPath% --proto_path%currentPath% %fileName%
%protocPath% %target%%currentPath% --proto_path%currentPath% %fileName%
:error
pause
exit
真正起作用编译出4个文件的代码是
%protocPath% --grpc_out%currentPath% --pluginprotoc-gen-grpc%pluginPath% --proto_path%currentPath% %fileName%
%protocPath% %target%%currentPath% --proto_path%currentPath% %fileName% 至此${projectDir}\out\build\${name}文件夹下会生成如下4个文件
helloworld.pb.h 消息类的头文件helloworld.pb.cc 消息类的实现helloworld.grpc.pb.h 服务类的头文件helloworld.grpc.pb.cc 服务类的实现
同时里面还包含所有的填充、序列化和获取请求和响应消息类型的 protocol buffer 代码和一个名为Greeter的类这个类中包含了
方便客户端调用的存根需要服务端实现的虚接口
实现服务端代码
以下是greeter_server.cc
#include iostream
#include memory
#include string#include absl/flags/flag.h
#include absl/flags/parse.h
#include absl/strings/str_format.h#include grpcpp/ext/proto_server_reflection_plugin.h
#include grpcpp/grpcpp.h
#include grpcpp/health_check_service_interface.h#ifdef BAZEL_BUILD
#include examples/protos/helloworld.grpc.pb.h
#else
#include helloworld.grpc.pb.h
#endifusing grpc::Server;
using grpc::ServerBuilder;
using grpc::ServerContext;
using grpc::Status;
using grpc::ServerWriter;
using grpc::ServerReader;
using grpc::ServerReaderWriter;
using helloworld::Greeter;
using helloworld::HelloReply;
using helloworld::HelloRequest;using std::string;ABSL_FLAG(uint16_t, port, 50051, Server port for the service);// Logic and data behind the servers behavior.
class GreeterServiceImpl final : public Greeter::Service
{Status SayHello(ServerContext* context, const HelloRequest* request, HelloReply* reply) override{std::cout -------- __FUNCTION__ -------- std::endl;string strName request-name();reply-set_message(Hello : strName);std::cout -------- __FUNCTION__ -------- std::endl;return Status::OK;}Status SayHelloStreamReply(ServerContext* context, const HelloRequest* request, ServerWriterHelloReply* writer){std::cout -------- __FUNCTION__ -------- std::endl;string strName request-name();HelloReply reply;reply.set_message(Hello strName);writer-Write(reply);for (unsigned int i 0; i 10; i){reply.clear_message();reply.set_message(This is Server Reply : std::to_string(i));writer-Write(reply);}std::cout -------- __FUNCTION__ -------- std::endl;return Status::OK;}Status StreamHelloReply(ServerContext* context, ServerReaderHelloRequest* reader, HelloReply* response){std::cout -------- __FUNCTION__ -------- std::endl;HelloRequest req;while (reader-Read(req)){std::cout Server got what you said req.name() std::endl;}response-set_message(Server got what you said req.name());std::cout -------- __FUNCTION__ -------- std::endl;return Status::OK;}Status StreamHelloStreamReply(ServerContext* context, ServerReaderWriter HelloReply, HelloRequest* stream){std::cout -------- __FUNCTION__ -------- std::endl;HelloRequest req;HelloReply reply;unsigned long uiCount 0ul;while (stream-Read(req)){std::cout Server got what you said req.name() std::endl;reply.clear_message();reply.set_message(This is Server count std::to_string(uiCount));stream-Write(reply);}std::cout -------- __FUNCTION__ -------- std::endl;return Status::OK;}
};void RunServer(uint16_t port) {std::string server_address absl::StrFormat(0.0.0.0:%d, port);GreeterServiceImpl service;grpc::EnableDefaultHealthCheckService(true);grpc::reflection::InitProtoReflectionServerBuilderPlugin();ServerBuilder builder;// Listen on the given address without any authentication mechanism.builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());// Register service as the instance through which well communicate with// clients. In this case it corresponds to an *synchronous* service.builder.RegisterService(service);// Finally assemble the server.std::unique_ptrServer server(builder.BuildAndStart());std::cout Server listening on server_address std::endl;// Wait for the server to shutdown. Note that some other thread must be// responsible for shutting down the server for this call to ever return.server-Wait();
}int main(int argc, char** argv) {absl::ParseCommandLine(argc, argv);RunServer(absl::GetFlag(FLAGS_port));return 0;
}可以看到里面有两部分代码。一部分是真正实现服务接口内在逻辑的代码逻辑都在GreeterServiceImpl 这个类中。另一部分是运行一个服务并使它监听固定端口的代码逻辑都在RunServer这个函数中。
实现客户端代码
以下是greeter_client.cc
#include iostream
#include memory
#include string
#include chrono
#include thread#include absl/flags/flag.h
#include absl/flags/parse.h#include grpcpp/grpcpp.h#ifdef BAZEL_BUILD
#include examples/protos/helloworld.grpc.pb.h
#else
#include helloworld.grpc.pb.h
#endifABSL_FLAG(std::string, target, localhost:50051, Server address);using grpc::Channel;
using grpc::ClientContext;
using grpc::Status;
using helloworld::Greeter;
using helloworld::HelloReply;
using helloworld::HelloRequest;
using std::thread;class GreeterClient {public:GreeterClient(std::shared_ptrChannel channel): stub_(Greeter::NewStub(channel)) {}// Assembles the clients payload, sends it and presents the response back// from the server.void SayHello(const std::string user){std::cout -------- __FUNCTION__ -------- std::endl;// Data we are sending to the server.HelloRequest request;request.set_name(user);// Container for the data we expect from the server.HelloReply reply;// Context for the client. It could be used to convey extra information to// the server and/or tweak certain RPC behaviors.ClientContext context;// The actual RPC.Status status stub_-SayHello(context, request, reply);// Act upon its status.if (status.ok()) {std::cout Server said reply.message() std::endl;} else {status.error_message();std::cout status.error_code() : status.error_message() std::endl;}std::cout -------- __FUNCTION__ -------- std::endl;}void SayHelloStreamReply(const std::string user){std::cout -------- __FUNCTION__ -------- std::endl;// Data we are sending to the server.HelloRequest request;request.set_name(user);// Context for the client. It could be used to convey extra information to// the server and/or tweak certain RPC behaviors.ClientContext context;HelloReply reply;// The actual RPC.auto Reader stub_-SayHelloStreamReply(context, request);while (Reader-Read(reply)){std::cout reply.message() std::endl;}if (!Reader-Finish().ok()){std::cout Reader-Finish().error_code() : Reader-Finish().error_message() std::endl;std::cout RPC failed std::endl;}std::cout -------- __FUNCTION__ -------- std::endl;}void StreamHelloReply(const std::string user){std::cout -------- __FUNCTION__ -------- std::endl;HelloReply reply;ClientContext context;auto Writer stub_-StreamHelloReply(context, reply);for (unsigned int i 0; i 10; i){// Data we are sending to the server.HelloRequest request;std::string strName user std::to_string(i);request.set_name(strName);Writer-Write(request);}Writer-WritesDone();if (!Writer-Finish().ok()){std::cout Writer-Finish().error_code() : Writer-Finish().error_message() std::endl;std::cout RPC failed std::endl;}else{std::cout reply.message() std::endl;}std::cout -------- __FUNCTION__ -------- std::endl;}void StreamHelloStreamReply(const std::string user){std::cout -------- __FUNCTION__ -------- std::endl;HelloReply reply;ClientContext context;std::shared_ptr ::grpc::ClientReaderWriter ::helloworld::HelloRequest, ::helloworld::HelloReply Stream stub_-StreamHelloStreamReply(context);thread t1([Stream, user]() {for (unsigned int i 0; i 20; i){// Data we are sending to the server.HelloRequest request;std::string strName user std::to_string(i);request.set_name(strName);Stream-Write(request);}Stream-WritesDone();});while (Stream-Read(reply)){std::cout reply.message() std::endl;}t1.join();if (!Stream-Finish().ok()){std::cout Stream-Finish().error_code() : Stream-Finish().error_message() std::endl;std::cout RPC failed std::endl;}std::cout -------- __FUNCTION__ -------- std::endl;}private:std::unique_ptrGreeter::Stub stub_;
};int main(int argc, char** argv) {absl::ParseCommandLine(argc, argv);// Instantiate the client. It requires a channel, out of which the actual RPCs// are created. This channel models a connection to an endpoint specified by// the argument --target which is the only expected argument.std::string target_str absl::GetFlag(FLAGS_target);// We indicate that the channel isnt authenticated (use of// InsecureChannelCredentials()).GreeterClient greeter(grpc::CreateChannel(target_str, grpc::InsecureChannelCredentials()));std::string strName User;greeter.SayHello(strName);Sleep(500);greeter.SayHelloStreamReply(strName);Sleep(500);greeter.StreamHelloReply(strName);Sleep(500);greeter.StreamHelloStreamReply(strName);return 0;
}客户端代码想要调用服务必须要使用到存根所以我们可以在代码里看到std::unique_ptrGreeter::Stub stub_。这样我们在客户端调用时就像是调用一个本地方法一样。
