1/*
2 *
3 * Copyright 2019 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// Binary server is an example server.
20package main
21
22import (
23	"context"
24	"flag"
25	"fmt"
26	"log"
27	"net"
28	"time"
29
30	"google.golang.org/grpc"
31	"google.golang.org/grpc/keepalive"
32
33	pb "google.golang.org/grpc/examples/features/proto/echo"
34)
35
36var port = flag.Int("port", 50052, "port number")
37
38var kaep = keepalive.EnforcementPolicy{
39	MinTime:             5 * time.Second, // If a client pings more than once every 5 seconds, terminate the connection
40	PermitWithoutStream: true,            // Allow pings even when there are no active streams
41}
42
43var kasp = keepalive.ServerParameters{
44	MaxConnectionIdle:     15 * time.Second, // If a client is idle for 15 seconds, send a GOAWAY
45	MaxConnectionAge:      30 * time.Second, // If any connection is alive for more than 30 seconds, send a GOAWAY
46	MaxConnectionAgeGrace: 5 * time.Second,  // Allow 5 seconds for pending RPCs to complete before forcibly closing connections
47	Time:                  5 * time.Second,  // Ping the client if it is idle for 5 seconds to ensure the connection is still active
48	Timeout:               1 * time.Second,  // Wait 1 second for the ping ack before assuming the connection is dead
49}
50
51func unaryEcho(ctx context.Context, req *pb.EchoRequest) (*pb.EchoResponse, error) {
52	return &pb.EchoResponse{Message: req.Message}, nil
53}
54
55func main() {
56	flag.Parse()
57
58	address := fmt.Sprintf(":%v", *port)
59	lis, err := net.Listen("tcp", address)
60	if err != nil {
61		log.Fatalf("failed to listen: %v", err)
62	}
63
64	s := grpc.NewServer(grpc.KeepaliveEnforcementPolicy(kaep), grpc.KeepaliveParams(kasp))
65	pb.RegisterEchoService(s, &pb.EchoService{UnaryEcho: unaryEcho})
66
67	if err := s.Serve(lis); err != nil {
68		log.Fatalf("failed to serve: %v", err)
69	}
70}
71