Fixed review comments

Fixed running as a windows service
Added logging to windows evenlog

service.go

@@ -2,11 +2,17 @@ package main
 
 import (
 	"os"
+	"runtime"
 
 	"github.com/hmage/golibs/log"
 	"github.com/kardianos/service"
 )
 
+const (
+	launchdStdoutPath = "/var/log/AdGuardHome.stdout.log"
+	launchdStderrPath = "/var/log/AdGuardHome.stderr.log"
+)
+
 // Represents the program that will be launched by a service or daemon
 type program struct {
 }
@@ -14,7 +20,7 @@ type program struct {
 // Start should quickly start the program
 func (p *program) Start(s service.Service) error {
 	// Start should not block. Do the actual work async.
-	args := options{}
+	args := options{runningAsService: true}
 	go run(args)
 	return nil
 }
@@ -23,6 +29,7 @@ func (p *program) Start(s service.Service) error {
 func (p *program) Stop(s service.Service) error {
 	// Stop should not block. Return with a few seconds.
 	cleanup()
+	os.Exit(0)
 	return nil
 }
 
@@ -33,6 +40,9 @@ func (p *program) Stop(s service.Service) error {
 // start -- starts the previously installed service
 // stop -- stops the previously installed service
 // restart - restarts the previously installed service
+// run - this is a special command that is not supposed to be used directly
+// it is specified when we register a service, and it indicates to the app
+// that it is being run as a service/daemon.
 func handleServiceControlAction(action string) {
 	log.Printf("Service control action: %s", action)
 
@@ -45,7 +55,9 @@ func handleServiceControlAction(action string) {
 		DisplayName:      "AdGuard Home service",
 		Description:      "AdGuard Home: Network-level blocker",
 		WorkingDirectory: pwd,
+		Arguments:        []string{"-s", "run"},
 	}
+	configureService(svcConfig)
 	prg := &program{}
 	s, err := service.New(prg, svcConfig)
 	if err != nil {
@@ -66,11 +78,100 @@ func handleServiceControlAction(action string) {
 		case service.StatusRunning:
 			log.Printf("Service is running")
 		}
+	} else if action == "run" {
+		err = s.Run()
+		if err != nil {
+			log.Fatalf("Failed to run service: %s", err)
+		}
 	} else {
+		if action == "uninstall" {
+			// In case of Windows and Linux when a running service is being uninstalled,
+			// it is just marked for deletion but not stopped
+			// So we explicitly stop it here
+			_ = s.Stop()
+		}
+
 		err = service.Control(s, action)
 		if err != nil {
 			log.Fatal(err)
 		}
-		log.Printf("Action %s has been done successfully", action)
+		log.Printf("Action %s has been done successfully on %s", action, service.ChosenSystem().String())
+
+		if action == "install" {
+			// Start automatically after install
+			err = service.Control(s, "start")
+			if err != nil {
+				log.Fatalf("Failed to start the service: %s", err)
+			}
+			log.Printf("Service has been started")
+		} else if action == "uninstall" {
+			cleanupService()
+		}
 	}
 }
+
+// configureService defines additional settings of the service
+func configureService(c *service.Config) {
+	c.Option = service.KeyValue{}
+
+	// OS X
+	// Redefines the launchd config file template
+	// The purpose is to enable stdout/stderr redirect by default
+	c.Option["LaunchdConfig"] = launchdConfig
+	// This key is used to start the job as soon as it has been loaded. For daemons this means execution at boot time, for agents execution at login.
+	c.Option["RunAtLoad"] = true
+
+	// POSIX
+	// Redirect StdErr & StdOut to files.
+	c.Option["LogOutput"] = true
+
+	// Windows
+	if runtime.GOOS == "windows" {
+		c.UserName = "NT AUTHORITY\\NetworkService"
+	}
+}
+
+// cleanupService called on the service uninstall, cleans up additional files if needed
+func cleanupService() {
+	if runtime.GOOS == "darwin" {
+		// Removing log files on cleanup and ignore errors
+		err := os.Remove(launchdStdoutPath)
+		if err != nil && !os.IsNotExist(err) {
+			log.Printf("cannot remove %s", launchdStdoutPath)
+		}
+		err = os.Remove(launchdStderrPath)
+		if err != nil && !os.IsNotExist(err) {
+			log.Printf("cannot remove %s", launchdStderrPath)
+		}
+	}
+}
+
+// Basically the same template as the one defined in github.com/kardianos/service
+// but with two additional keys - StandardOutPath and StandardErrorPath
+var launchdConfig = `<?xml version='1.0' encoding='UTF-8'?>
+<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN"
+"http://www.apple.com/DTDs/PropertyList-1.0.dtd" >
+<plist version='1.0'>
+<dict>
+<key>Label</key><string>{{html .Name}}</string>
+<key>ProgramArguments</key>
+<array>
+        <string>{{html .Path}}</string>
+{{range .Config.Arguments}}
+        <string>{{html .}}</string>
+{{end}}
+</array>
+{{if .UserName}}<key>UserName</key><string>{{html .UserName}}</string>{{end}}
+{{if .ChRoot}}<key>RootDirectory</key><string>{{html .ChRoot}}</string>{{end}}
+{{if .WorkingDirectory}}<key>WorkingDirectory</key><string>{{html .WorkingDirectory}}</string>{{end}}
+<key>SessionCreate</key><{{bool .SessionCreate}}/>
+<key>KeepAlive</key><{{bool .KeepAlive}}/>
+<key>RunAtLoad</key><{{bool .RunAtLoad}}/>
+<key>Disabled</key><false/>
+<key>StandardOutPath</key>
+<string>` + launchdStdoutPath + `</string>
+<key>StandardErrorPath</key>
+<string>` + launchdStderrPath + `</string>
+</dict>
+</plist>
+`