1 // Copyright 2023 gRPC authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include <iostream>
16 #include <memory>
17 #include <string>
18 #include <unordered_set>
19
20 #include "absl/flags/flag.h"
21 #include "absl/flags/parse.h"
22 #include "absl/strings/str_format.h"
23 #include "absl/synchronization/mutex.h"
24
25 #include <grpcpp/ext/proto_server_reflection_plugin.h>
26 #include <grpcpp/grpcpp.h>
27 #include <grpcpp/health_check_service_interface.h>
28
29 #ifdef BAZEL_BUILD
30 #include "examples/protos/helloworld.grpc.pb.h"
31 #else
32 #include "helloworld.grpc.pb.h"
33 #endif
34
35 ABSL_FLAG(uint16_t, port, 50051, "Server port for the service");
36
37 using grpc::CallbackServerContext;
38 using grpc::Server;
39 using grpc::ServerBuilder;
40 using grpc::ServerUnaryReactor;
41 using grpc::Status;
42 using grpc::StatusCode;
43 using helloworld::Greeter;
44 using helloworld::HelloReply;
45 using helloworld::HelloRequest;
46
47 // Logic and data behind the server's behavior.
48 class GreeterServiceImpl final : public Greeter::CallbackService {
SayHello(CallbackServerContext * context,const HelloRequest * request,HelloReply * reply)49 ServerUnaryReactor* SayHello(CallbackServerContext* context,
50 const HelloRequest* request,
51 HelloReply* reply) override {
52 ServerUnaryReactor* reactor = context->DefaultReactor();
53 Status status;
54 // Checks the length of name
55 if (request->name().empty() || request->name().length() > 10) {
56 // Returns an error status with error code and message.
57 status = Status(StatusCode::INVALID_ARGUMENT,
58 "Length of `Name` should be between 1 and 10");
59 } else {
60 reply->set_message(absl::StrFormat("Hello %s", request->name()));
61 status = Status::OK;
62 }
63 reactor->Finish(status);
64 return reactor;
65 }
66
67 private:
68 absl::Mutex mu_;
69 std::unordered_set<std::string> request_name_set_;
70 };
71
RunServer(uint16_t port)72 void RunServer(uint16_t port) {
73 std::string server_address = absl::StrFormat("0.0.0.0:%d", port);
74 GreeterServiceImpl service;
75
76 grpc::EnableDefaultHealthCheckService(true);
77 grpc::reflection::InitProtoReflectionServerBuilderPlugin();
78 ServerBuilder builder;
79 // Listen on the given address without any authentication mechanism.
80 builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());
81 // Register "service" as the instance through which we'll communicate with
82 // clients. In this case it corresponds to an *synchronous* service.
83 builder.RegisterService(&service);
84 // Finally assemble the server.
85 std::unique_ptr<Server> server(builder.BuildAndStart());
86 std::cout << "Server listening on " << server_address << std::endl;
87
88 // Wait for the server to shutdown. Note that some other thread must be
89 // responsible for shutting down the server for this call to ever return.
90 server->Wait();
91 }
92
main(int argc,char ** argv)93 int main(int argc, char** argv) {
94 absl::ParseCommandLine(argc, argv);
95 RunServer(absl::GetFlag(FLAGS_port));
96 return 0;
97 }
98