Support installation as a service

vendor/github.com/kardianos/service/service_systemd_linux.go

@@ -0,0 +1,175 @@
+// Copyright 2015 Daniel Theophanes.
+// Use of this source code is governed by a zlib-style
+// license that can be found in the LICENSE file.
+
+package service
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+	"text/template"
+)
+
+func isSystemd() bool {
+	if _, err := os.Stat("/run/systemd/system"); err == nil {
+		return true
+	}
+	return false
+}
+
+type systemd struct {
+	i Interface
+	*Config
+}
+
+func newSystemdService(i Interface, c *Config) (Service, error) {
+	s := &systemd{
+		i:      i,
+		Config: c,
+	}
+
+	return s, nil
+}
+
+func (s *systemd) String() string {
+	if len(s.DisplayName) > 0 {
+		return s.DisplayName
+	}
+	return s.Name
+}
+
+// Systemd services should be supported, but are not currently.
+var errNoUserServiceSystemd = errors.New("User services are not supported on systemd.")
+
+func (s *systemd) configPath() (cp string, err error) {
+	if s.Option.bool(optionUserService, optionUserServiceDefault) {
+		err = errNoUserServiceSystemd
+		return
+	}
+	cp = "/etc/systemd/system/" + s.Config.Name + ".service"
+	return
+}
+func (s *systemd) template() *template.Template {
+	return template.Must(template.New("").Funcs(tf).Parse(systemdScript))
+}
+
+func (s *systemd) Install() error {
+	confPath, err := s.configPath()
+	if err != nil {
+		return err
+	}
+	_, err = os.Stat(confPath)
+	if err == nil {
+		return fmt.Errorf("Init already exists: %s", confPath)
+	}
+
+	f, err := os.Create(confPath)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	path, err := s.execPath()
+	if err != nil {
+		return err
+	}
+
+	var to = &struct {
+		*Config
+		Path         string
+		ReloadSignal string
+		PIDFile      string
+	}{
+		s.Config,
+		path,
+		s.Option.string(optionReloadSignal, ""),
+		s.Option.string(optionPIDFile, ""),
+	}
+
+	err = s.template().Execute(f, to)
+	if err != nil {
+		return err
+	}
+
+	err = run("systemctl", "enable", s.Name+".service")
+	if err != nil {
+		return err
+	}
+	return run("systemctl", "daemon-reload")
+}
+
+func (s *systemd) Uninstall() error {
+	err := run("systemctl", "disable", s.Name+".service")
+	if err != nil {
+		return err
+	}
+	cp, err := s.configPath()
+	if err != nil {
+		return err
+	}
+	if err := os.Remove(cp); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (s *systemd) Logger(errs chan<- error) (Logger, error) {
+	if system.Interactive() {
+		return ConsoleLogger, nil
+	}
+	return s.SystemLogger(errs)
+}
+func (s *systemd) SystemLogger(errs chan<- error) (Logger, error) {
+	return newSysLogger(s.Name, errs)
+}
+
+func (s *systemd) Run() (err error) {
+	err = s.i.Start(s)
+	if err != nil {
+		return err
+	}
+
+	s.Option.funcSingle(optionRunWait, func() {
+		var sigChan = make(chan os.Signal, 3)
+		signal.Notify(sigChan, syscall.SIGTERM, os.Interrupt)
+		<-sigChan
+	})()
+
+	return s.i.Stop(s)
+}
+
+func (s *systemd) Start() error {
+	return run("systemctl", "start", s.Name+".service")
+}
+
+func (s *systemd) Stop() error {
+	return run("systemctl", "stop", s.Name+".service")
+}
+
+func (s *systemd) Restart() error {
+	return run("systemctl", "restart", s.Name+".service")
+}
+
+const systemdScript = `[Unit]
+Description={{.Description}}
+ConditionFileIsExecutable={{.Path|cmdEscape}}
+
+[Service]
+StartLimitInterval=5
+StartLimitBurst=10
+ExecStart={{.Path|cmdEscape}}{{range .Arguments}} {{.|cmd}}{{end}}
+{{if .ChRoot}}RootDirectory={{.ChRoot|cmd}}{{end}}
+{{if .WorkingDirectory}}WorkingDirectory={{.WorkingDirectory|cmdEscape}}{{end}}
+{{if .UserName}}User={{.UserName}}{{end}}
+{{if .ReloadSignal}}ExecReload=/bin/kill -{{.ReloadSignal}} "$MAINPID"{{end}}
+{{if .PIDFile}}PIDFile={{.PIDFile|cmd}}{{end}}
+Restart=always
+RestartSec=120
+EnvironmentFile=-/etc/sysconfig/{{.Name}}
+
+[Install]
+WantedBy=multi-user.target
+`