1 #include "greeter.grpc.fb.h" 2 #include "greeter_generated.h" 3 4 #include <grpc++/grpc++.h> 5 6 #include <iostream> 7 #include <memory> 8 #include <string> 9 10 class GreeterClient { 11 public: 12 GreeterClient(std::shared_ptr<grpc::Channel> channel) 13 : stub_(Greeter::NewStub(channel)) {} 14 15 std::string SayHello(const std::string &name) { 16 flatbuffers::grpc::MessageBuilder mb; 17 auto name_offset = mb.CreateString(name); 18 auto request_offset = CreateHelloRequest(mb, name_offset); 19 mb.Finish(request_offset); 20 auto request_msg = mb.ReleaseMessage<HelloRequest>(); 21 22 flatbuffers::grpc::Message<HelloReply> response_msg; 23 24 grpc::ClientContext context; 25 26 auto status = stub_->SayHello(&context, request_msg, &response_msg); 27 if (status.ok()) { 28 const HelloReply *response = response_msg.GetRoot(); 29 return response->message()->str(); 30 } else { 31 std::cerr << status.error_code() << ": " << status.error_message() 32 << std::endl; 33 return "RPC failed"; 34 } 35 } 36 37 void SayManyHellos(const std::string &name, int num_greetings, 38 std::function<void(const std::string &)> callback) { 39 flatbuffers::grpc::MessageBuilder mb; 40 auto name_offset = mb.CreateString(name); 41 auto request_offset = 42 CreateManyHellosRequest(mb, name_offset, num_greetings); 43 mb.Finish(request_offset); 44 auto request_msg = mb.ReleaseMessage<ManyHellosRequest>(); 45 46 flatbuffers::grpc::Message<HelloReply> response_msg; 47 48 grpc::ClientContext context; 49 50 auto stream = stub_->SayManyHellos(&context, request_msg); 51 while (stream->Read(&response_msg)) { 52 const HelloReply *response = response_msg.GetRoot(); 53 callback(response->message()->str()); 54 } 55 auto status = stream->Finish(); 56 if (!status.ok()) { 57 std::cerr << status.error_code() << ": " << status.error_message() 58 << std::endl; 59 callback("RPC failed"); 60 } 61 } 62 63 private: 64 std::unique_ptr<Greeter::Stub> stub_; 65 }; 66 67 int main(int argc, char **argv) { 68 std::string server_address("localhost:50051"); 69 70 auto channel = 71 grpc::CreateChannel(server_address, grpc::InsecureChannelCredentials()); 72 GreeterClient greeter(channel); 73 74 std::string name("world"); 75 76 std::string message = greeter.SayHello(name); 77 std::cerr << "Greeter received: " << message << std::endl; 78 79 int num_greetings = 10; 80 greeter.SayManyHellos(name, num_greetings, [](const std::string &message) { 81 std::cerr << "Greeter received: " << message << std::endl; 82 }); 83 84 return 0; 85 } 86
