daemon 是没有任何依赖的 Go(golang)服务守护进程包。
简单示例 (just install self as daemon):
package mainimport ( "fmt" "log" "github.com/takama/daemon")func main() { service, err := daemon.New("name", "description") if err != nil { log.Fatal("Error: ", err) } status, err := service.Install() if err != nil { log.Fatal(status, "\nError: ", err) } fmt.Println(status)}
实际示例:
// Example of the daemon with echo servicepackage mainimport ( "fmt" "log" "net" "os" "os/signal" "syscall" "github.com/takama/daemon")const ( // name of the service, match with executable file name name = "myservice" description = "My Echo Service" // port which daemon should be listen port = ":9977")// Service has embedded daemontype Service struct { daemon.Daemon}// Manage by daemon commands or run the daemonfunc (service *Service) Manage() (string, error) { usage := "Usage: myservice install | remove | start | stop | status" // if received any kind of command, do it if len(os.Args) > 1 { command := os.Args[1] switch command { case "install": return service.Install() case "remove": return service.Remove() case "start": return service.Start() case "stop": return service.Stop() case "status": return service.Status() default: return usage, nil } } // Do something, call your goroutines, etc // Set up channel on which to send signal notifications. // We must use a buffered channel or risk missing the signal // if we're not ready to receive when the signal is sent. interrupt := make(chan os.Signal, 1) signal.Notify(interrupt, os.Interrupt, os.Kill, syscall.SIGTERM) // Set up listener for defined host and port listener, err := net.Listen("tcp", port) if err != nil { return "Possibly was a problem with the port binding", err } // set up channel on which to send accepted connections listen := make(chan net.Conn, 100) go acceptConnection(listener, listen) // loop work cycle with accept connections or interrupt // by system signal for { select { case conn := <-listen: go handleClient(conn) case killSignal := <-interrupt: log.Println("Got signal:", killSignal) log.Println("Stoping listening on ", listener.Addr()) listener.Close() if killSignal == os.Interrupt { return "Daemon was interruped by system signal", nil } return "Daemon was killed", nil } } // never happen, but need to complete code return usage, nil}// Accept a client connection and collect it in a channelfunc acceptConnection(listener net.Listener, listen chan<- net.Conn) { for { conn, err := listener.Accept() if err != nil { continue } listen <- conn }}func handleClient(client net.Conn) { for { buf := make([]byte, 4096) numbytes, err := client.Read(buf) if numbytes == 0 || err != nil { return } client.Write(buf) }}func main() { srv, err := daemon.New(name, description) if err != nil { fmt.Println("Error: ", err) os.Exit(1) } service := &Service{srv} status, err := service.Manage() if err != nil { fmt.Println(status, "\nError: ", err) os.Exit(1) } fmt.Println(status)}