1 /*
2 *
3 * Copyright 2023 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18
19 #include <iostream>
20 #include <memory>
21 #include <string>
22
23 #include "absl/flags/flag.h"
24 #include "absl/flags/parse.h"
25 #include "absl/strings/str_cat.h"
26
27 #include <grpcpp/ext/admin_services.h>
28 #include <grpcpp/ext/proto_server_reflection_plugin.h>
29 #include <grpcpp/grpcpp.h>
30 #include <grpcpp/health_check_service_interface.h>
31 #include <grpcpp/xds_server_builder.h>
32
33 #ifdef BAZEL_BUILD
34 #include "examples/protos/helloworld.grpc.pb.h"
35 #else
36 #include "helloworld.grpc.pb.h"
37 #endif
38
39 ABSL_FLAG(int32_t, port, 50051, "Server port for service.");
40 ABSL_FLAG(int32_t, maintenance_port, 50052,
41 "Server port for maintenance if --secure is used.");
42 ABSL_FLAG(bool, secure, true, "Secure mode");
43
44 using grpc::CallbackServerContext;
45 using grpc::Server;
46 using grpc::ServerBuilder;
47 using grpc::ServerUnaryReactor;
48 using grpc::Status;
49 using helloworld::Greeter;
50 using helloworld::HelloReply;
51 using helloworld::HelloRequest;
52
53 // Logic and data behind the server's behavior.
54 class GreeterServiceImpl final : public Greeter::CallbackService {
SayHello(CallbackServerContext * context,const HelloRequest * request,HelloReply * reply)55 ServerUnaryReactor* SayHello(CallbackServerContext* context,
56 const HelloRequest* request,
57 HelloReply* reply) override {
58 std::string prefix("Hello ");
59 reply->set_message(prefix + request->name());
60
61 ServerUnaryReactor* reactor = context->DefaultReactor();
62 reactor->Finish(Status::OK);
63 return reactor;
64 }
65 };
66
RunServer()67 void RunServer() {
68 grpc::EnableDefaultHealthCheckService(true);
69 grpc::reflection::InitProtoReflectionServerBuilderPlugin();
70 int port = absl::GetFlag(FLAGS_port);
71 int maintenance_port = absl::GetFlag(FLAGS_maintenance_port);
72 grpc::XdsServerBuilder xds_builder;
73 ServerBuilder builder;
74 std::unique_ptr<Server> xds_enabled_server;
75 std::unique_ptr<Server> server;
76 GreeterServiceImpl service;
77 // Register "service" as the instance through which we'll communicate with
78 // clients. In this case it corresponds to an *synchronous* service.
79 xds_builder.RegisterService(&service);
80 if (absl::GetFlag(FLAGS_secure)) {
81 // Listen on the given address with XdsServerCredentials and a fallback of
82 // InsecureServerCredentials
83 xds_builder.AddListeningPort(
84 absl::StrCat("0.0.0.0:", port),
85 grpc::XdsServerCredentials(grpc::InsecureServerCredentials()));
86 xds_enabled_server = xds_builder.BuildAndStart();
87 gpr_log(GPR_INFO, "Server starting on 0.0.0.0:%d", port);
88 grpc::AddAdminServices(&builder);
89 // For the maintenance server, do not use any authentication mechanism.
90 builder.AddListeningPort(absl::StrCat("0.0.0.0:", maintenance_port),
91 grpc::InsecureServerCredentials());
92 server = builder.BuildAndStart();
93 gpr_log(GPR_INFO, "Maintenance server listening on 0.0.0.0:%d",
94 maintenance_port);
95 } else {
96 grpc::AddAdminServices(&xds_builder);
97 // Listen on the given address without any authentication mechanism.
98 builder.AddListeningPort(absl::StrCat("0.0.0.0:", port),
99 grpc::InsecureServerCredentials());
100 server = xds_builder.BuildAndStart();
101 gpr_log(GPR_INFO, "Server listening on 0.0.0.0:%d", port);
102 }
103
104 // Wait for the server to shutdown. Note that some other thread must be
105 // responsible for shutting down the server for this call to ever return.
106 server->Wait();
107 }
108
main(int argc,char ** argv)109 int main(int argc, char** argv) {
110 absl::ParseCommandLine(argc, argv);
111 RunServer();
112 return 0;
113 }
114