util/tcp/server.go

package tcp

import (
	"fmt"
	"log"
	"net"
	"os"
	"os/signal"
	"syscall"
)

// NewTCPServer make TCP server
func NewTCPServer(addr string, cb func(*net.TCPConn)) {
	logger := log.New(os.Stdout, "INFO: ", log.LstdFlags)

	errc := make(chan error)
	go func() {
		c := make(chan os.Signal)
		signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
		errc <- fmt.Errorf("%s", <-c)
	}()

	tcpaddr, err := net.ResolveTCPAddr("tcp", addr)
	if err != nil {
		logger.Fatalf("listen error: %v", err)
		return
	}

	listen, err := net.ListenTCP("tcp", tcpaddr)
	if err != nil {
		logger.Fatalf("listen error: %v", err)
		return
	}
	defer listen.Close()

	go func() {
		logger.Println("TCP Listen", addr)
		for {
			conn, err := listen.AcceptTCP()
			if err != nil {
				errc <- err
				logger.Fatalf("accept error: %v", err)
				break
			}
			go cb(conn)
		}
		logger.Println("Exit server", "Quit")
	}()

	logger.Println("TCP Service Exit", <-errc)
}