Abstract kardianos/service behind pkg/service

Signed-off-by: Kimmo Lehto <klehto@mirantis.com>

cmd/start/start.go

@@ -20,9 +20,7 @@ import (
 	"fmt"
 	"os"
 
-	"github.com/k0sproject/k0s/pkg/install"
-
-	"github.com/kardianos/service"
+	"github.com/k0sproject/k0s/pkg/service"
 	"github.com/spf13/cobra"
 )
 
@@ -34,16 +32,24 @@ func NewStartCmd() *cobra.Command {
 			if os.Geteuid() != 0 {
 				return fmt.Errorf("this command must be run as root")
 			}
-			svc, err := install.InstalledService()
+			svc, err := service.InstalledK0sService()
+			if err != nil {
+				return err
+			}
+
+			status, err := svc.Status()
 			if err != nil {
 				return err
 			}
-			status, _ := svc.Status()
 			if status == service.StatusRunning {
 				return fmt.Errorf("already running")
 			}
-			return svc.Start()
+
+			if err := svc.Start(); err != nil {
+				return fmt.Errorf("failed to start the service: %w", err)
+			}
+
+			return nil
 		},
 	}
-
 }

cmd/stop/stop.go

@@ -20,9 +20,7 @@ import (
 	"fmt"
 	"os"
 
-	"github.com/k0sproject/k0s/pkg/install"
-
-	"github.com/kardianos/service"
+	"github.com/k0sproject/k0s/pkg/service"
 	"github.com/spf13/cobra"
 )
 
@@ -34,19 +32,24 @@ func NewStopCmd() *cobra.Command {
 			if os.Geteuid() != 0 {
 				return fmt.Errorf("this command must be run as root")
 			}
-			svc, err := install.InstalledService()
+			svc, err := service.InstalledK0sService()
 			if err != nil {
 				return err
 			}
+
 			status, err := svc.Status()
 			if err != nil {
 				return err
 			}
 			if status == service.StatusStopped {
 				return fmt.Errorf("already stopped")
 			}
-			return svc.Stop()
+
+			if err := svc.Stop(); err != nil {
+				return fmt.Errorf("failed to stop the service: %w", err)
+			}
+
+			return nil
 		},
 	}
-
 }

pkg/install/linux_openrc.go

@@ -17,8 +17,8 @@ limitations under the License.
 package install
 
 const openRCScript = `#!/sbin/openrc-run
-{{- if .Option.Environment}}{{range .Option.Environment}}
-export {{.}}{{end}}{{- end}}
+{{range $key, value := .EnvVars}}
+export {{$key}}={{$value}}{{- end}}
 supervisor=supervise-daemon
 name="{{.DisplayName}}"
 description="{{.Description}}"

pkg/install/linux_sysv.go

@@ -32,8 +32,8 @@ const sysvScript = `#!/bin/sh
 # Description:       {{.Description}}
 ### END INIT INFO
 
-{{- if .Option.Environment}}{{range .Option.Environment}}
-export {{.}}{{end}}{{- end}}
+{{range $key, value := .EnvVars}}
+export {{$key}}={{$value}}{{- end}}
 
 cmd="{{.Path}}{{range .Arguments}} {{.|cmd}}{{end}}"
 

pkg/install/linux_upstart.go

@@ -18,8 +18,8 @@ package install
 
 const upstartScript = `# {{.Description}}
 
-{{- if .Option.Environment}}{{range .Option.Environment}}
-env {{.}}{{end}}{{- end}}
+{{range $key, value := .EnvVars}}
+env {{$key}}={{$value}}{{- end}}
 
 {{if .DisplayName}}description    "{{.DisplayName}}"{{end}}
 

pkg/install/service.go

@@ -17,109 +17,68 @@ limitations under the License.
 package install
 
 import (
-	"errors"
 	"fmt"
 	"strings"
 
-	"github.com/kardianos/service"
+	"github.com/k0sproject/k0s/pkg/service"
 	"github.com/sirupsen/logrus"
 )
 
-var (
-	k0sServiceName = "k0s"
-	k0sDescription = "k0s - Zero Friction Kubernetes"
-)
-
-type Program struct{}
-
-func (p *Program) Start(service.Service) error {
-	// Start should not block. Do the actual work async.
-	return nil
-}
-
-func (p *Program) Stop(service.Service) error {
-	// Stop should not block. Return with a few seconds.
-	return nil
-}
-
-// InstalledService returns a k0s service if one has been installed on the host or an error otherwise.
-func InstalledService() (service.Service, error) {
-	prg := &Program{}
-	for _, role := range []string{"controller", "worker"} {
-		c := GetServiceConfig(role)
-		s, err := service.New(prg, c)
-		if err != nil {
-			return nil, err
-		}
-		_, err = s.Status()
-
-		if err != nil && errors.Is(err, service.ErrNotInstalled) {
-			continue
-		}
-		if err != nil {
-			return nil, err
-		}
-		return s, nil
-	}
-
-	var s service.Service
-	return s, fmt.Errorf("k0s has not been installed as a service")
-}
-
 // EnsureService installs the k0s service, per the given arguments, and the detected platform
 func EnsureService(args []string, envVars []string, force bool) error {
 	var deps []string
 	var svcConfig *service.Config
 
-	prg := &Program{}
 	for _, v := range args {
 		if v == "controller" || v == "worker" {
-			svcConfig = GetServiceConfig(v)
+			svcConfig = service.K0sConfig(v)
 			break
 		}
 	}
 
-	s, err := service.New(prg, svcConfig)
-	if err != nil {
-		return err
-	}
+	s, err := service.NewService(svcConfig)
 
 	// fetch service type
 	svcType := s.Platform()
 	switch svcType {
 	case "linux-openrc":
 		deps = []string{"need cgroups", "need net", "use dns", "after firewall"}
-		svcConfig.Option = map[string]interface{}{
+		svcConfig.Options = map[string]interface{}{
 			"OpenRCScript": openRCScript,
 		}
 	case "linux-upstart":
-		svcConfig.Option = map[string]interface{}{
+		svcConfig.Options = map[string]interface{}{
 			"UpstartScript": upstartScript,
 		}
 	case "unix-systemv":
-		svcConfig.Option = map[string]interface{}{
+		svcConfig.Options = map[string]interface{}{
 			"SystemdScript": sysvScript,
 		}
 	case "linux-systemd":
 		deps = []string{"After=network-online.target", "Wants=network-online.target"}
-		svcConfig.Option = map[string]interface{}{
+		svcConfig.Options = map[string]interface{}{
 			"SystemdScript": systemdScript,
 			"LimitNOFILE":   999999,
 		}
 	default:
 	}
 
 	if len(envVars) > 0 {
-		svcConfig.Option["Environment"] = envVars
+		svcConfig.EnvVars = prepareEnvVars(envVars)
 	}
 
 	svcConfig.Dependencies = deps
 	svcConfig.Arguments = args
 	if force {
 		logrus.Infof("Uninstalling %s service", svcConfig.Name)
-		err = s.Uninstall()
-		if err != nil && !errors.Is(err, service.ErrNotInstalled) {
-			logrus.Warnf("failed to uninstall service: %v", err)
+		status, err := s.Status()
+		if err != nil {
+			logrus.Warnf("failed to get service status: %v", err)
+		}
+		if status != service.StatusNotInstalled {
+			if err := s.Uninstall(); err != nil {
+				logrus.Warnf("failed to uninstall service: %v", err)
+			}
 		}
 	}
 	logrus.Infof("Installing %s service", svcConfig.Name)
@@ -131,33 +90,16 @@ func EnsureService(args []string, envVars []string, force bool) error {
 }
 
 func UninstallService(role string) error {
-	prg := &Program{}
-
-	if role == "controller+worker" {
-		role = "controller"
-	}
-
-	svcConfig := GetServiceConfig(role)
-	s, err := service.New(prg, svcConfig)
+	s, err := service.InstalledK0sService()
 	if err != nil {
-		return err
+		return fmt.Errorf("uninstall service: %w", err)
 	}
 
-	return s.Uninstall()
-}
-
-func GetServiceConfig(role string) *service.Config {
-	var k0sDisplayName string
-
-	if role == "controller" || role == "worker" {
-		k0sDisplayName = "k0s " + role
-		k0sServiceName = "k0s" + role
-	}
-	return &service.Config{
-		Name:        k0sServiceName,
-		DisplayName: k0sDisplayName,
-		Description: k0sDescription,
+	if err := s.Uninstall(); err != nil {
+		return fmt.Errorf("uninstall service: %w", err)
 	}
+
+	return nil
 }
 
 func prepareEnvVars(envVars []string) map[string]string {

pkg/service/config.go

@@ -0,0 +1,12 @@
+package service
+
+// Config describes a configuration for a system service
+type Config struct {
+	Name         string
+	DisplayName  string
+	Description  string
+	Arguments    []string
+	EnvVars      map[string]string
+	Options      map[string]any
+	Dependencies []string
+}