Pare down InitSystem interface

By reducing the surface, we make it easier to implement other backends (mock & kubelet)
kubernetes-sigs · Jul 25, 2020 · c77db63 · c77db63
1 parent e4a5ffd
commit c77db63
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Showing 5 changed files with 36 additions and 64 deletions.
diff --git a/cmd/init.go b/cmd/init.go
@@ -48,24 +48,8 @@ var initCmd = &cobra.Command{
 			log.Fatalf("[initsystem] Error detecting the init system: %s", err)
 		}
 
-		active, err := initSystem.IsActive(constants.UnitFileBaseName)
-		if err != nil {
-			log.Fatalf("[start] Error checking if etcd service is active: %s", err)
-		}
-		if active {
-			if err := initSystem.Stop(constants.UnitFileBaseName); err != nil {
-				log.Fatalf("[start] Error stopping existing etcd service: %s", err)
-			}
-		}
-
-		enabled, err := initSystem.IsEnabled(constants.UnitFileBaseName)
-		if err != nil {
-			log.Fatalf("[install] Error checking if etcd service is enabled: %s", err)
-		}
-		if enabled {
-			if err := initSystem.Disable(constants.UnitFileBaseName); err != nil {
-				log.Fatalf("[install] Error disabling existing etcd service: %s", err)
-			}
+		if err := initSystem.DisableAndStopService(constants.UnitFileBaseName); err != nil {
+			log.Fatalf("[install] Error disabling and stopping etcd service: %s", err)
 		}
 
 		exists, err := util.Exists(etcdAdmConfig.DataDir)

diff --git a/cmd/join.go b/cmd/join.go
@@ -58,24 +58,8 @@ var joinCmd = &cobra.Command{
 			log.Fatalf("[initsystem] Error detecting the init system: %s", err)
 		}
 
-		active, err := initSystem.IsActive(constants.UnitFileBaseName)
-		if err != nil {
-			log.Fatalf("[start] Error checking if etcd service is active: %s", err)
-		}
-		if active {
-			if err := initSystem.Stop(constants.UnitFileBaseName); err != nil {
-				log.Fatalf("[start] Error stopping existing etcd service: %s", err)
-			}
-		}
-
-		enabled, err := initSystem.IsEnabled(constants.UnitFileBaseName)
-		if err != nil {
-			log.Fatalf("[start] Error checking if etcd service is enabled: %s", err)
-		}
-		if enabled {
-			if err := initSystem.Disable(constants.UnitFileBaseName); err != nil {
-				log.Fatalf("[start] Error disabling existing etcd service: %s", err)
-			}
+		if err := initSystem.DisableAndStopService(constants.UnitFileBaseName); err != nil {
+			log.Fatalf("[install] Error disabling and stopping etcd service: %s", err)
 		}
 
 		// cert management

diff --git a/cmd/reset.go b/cmd/reset.go
@@ -90,20 +90,11 @@ var resetCmd = &cobra.Command{
 					log.Println("[membership] Member was removed")
 				}
 			}
-			// Disable etcd service
-			if err := initSystem.Stop(constants.UnitFileBaseName); err != nil {
-				log.Fatalf("[reset] Error stopping existing etcd service: %s", err)
-			}
 		}
-		enabled, err := initSystem.IsEnabled(constants.UnitFileBaseName)
-		if err != nil {
-			log.Fatalf("[reset] Error checking if etcd service is enabled: %s", err)
-		}
-		if enabled {
-			if err := initSystem.Disable(constants.UnitFileBaseName); err != nil {
-				log.Fatalf("[reset] Error disabling existing etcd service: %s", err)
-			}
+		if err := initSystem.DisableAndStopService(constants.UnitFileBaseName); err != nil {
+			log.Fatalf("[reset] Error stopping etcd: %s", err)
 		}
+
 		// Remove etcd datastore
 		if err = os.RemoveAll(etcdAdmConfig.DataDir); err != nil {
 			log.Print(err)

diff --git a/initsystem/initsystem.go b/initsystem/initsystem.go
@@ -23,12 +23,7 @@ import (
 
 // InitSystem is the interface that describe behaviors of an init system
 type InitSystem interface {
-	Start(service string) error
-	Stop(service string) error
-	Enable(service string) error
-	Disable(service string) error
 	IsActive(service string) (bool, error)
-	IsEnabled(service string) (bool, error)
 	EnableAndStartService(service string) error
 	DisableAndStopService(service string) error
 }

diff --git a/initsystem/systemd.go b/initsystem/systemd.go
@@ -32,7 +32,7 @@ func (s SystemdInitSystem) reloadSystemd() error {
 }
 
 // Start a service
-func (s SystemdInitSystem) Start(service string) error {
+func (s SystemdInitSystem) start(service string) error {
 	// Before we try to start any service, make sure that systemd is ready
 	if err := s.reloadSystemd(); err != nil {
 		return err
@@ -45,7 +45,7 @@ func (s SystemdInitSystem) Start(service string) error {
 }
 
 // Stop a service
-func (s SystemdInitSystem) Stop(service string) error {
+func (s SystemdInitSystem) stop(service string) error {
 	// Before we try to start any service, make sure that systemd is ready
 	if err := s.reloadSystemd(); err != nil {
 		return err
@@ -58,7 +58,7 @@ func (s SystemdInitSystem) Stop(service string) error {
 }
 
 // Enable a service
-func (s SystemdInitSystem) Enable(service string) error {
+func (s SystemdInitSystem) enable(service string) error {
 	// Before we try to enable any service, make sure that systemd is ready
 	if err := s.reloadSystemd(); err != nil {
 		return err
@@ -71,7 +71,7 @@ func (s SystemdInitSystem) Enable(service string) error {
 }
 
 // Disable a service
-func (s SystemdInitSystem) Disable(service string) error {
+func (s SystemdInitSystem) disable(service string) error {
 	// Before we try to disable any service, make sure that systemd is ready
 	if err := s.reloadSystemd(); err != nil {
 		return err
@@ -85,18 +85,36 @@ func (s SystemdInitSystem) Disable(service string) error {
 
 // EnableAndStartService enables and starts the etcd service
 func (s SystemdInitSystem) EnableAndStartService(service string) error {
-	if err := s.Enable(service); err != nil {
+	if err := s.enable(service); err != nil {
 		return err
 	}
-	return s.Start(service)
+	return s.start(service)
 }
 
 // DisableAndStopService disables and stops the etcd service
 func (s SystemdInitSystem) DisableAndStopService(service string) error {
-	if err := s.Disable(service); err != nil {
-		return err
+	enabled, err := s.isEnabled(service)
+	if err != nil {
+		return fmt.Errorf("error checking if etcd service is enabled: %w", err)
+	}
+	if enabled {
+		if err := s.disable(service); err != nil {
+			return err
+		}
+	}
+
+	active, err := s.IsActive(service)
+	if err != nil {
+		return fmt.Errorf("error checking if etcd service is active: %w", err)
 	}
-	return s.Stop(service)
+
+	if active {
+		if err := s.stop(service); err != nil {
+			return err
+		}
+	}
+
+	return nil
 }
 
 // IsActive checks if the systemd unit is active
@@ -115,8 +133,8 @@ func (s SystemdInitSystem) IsActive(service string) (bool, error) {
 	return true, nil
 }
 
-// IsEnabled checks if the systemd unit is enabled
-func (s SystemdInitSystem) IsEnabled(service string) (bool, error) {
+// isEnabled checks if the systemd unit is enabled
+func (s SystemdInitSystem) isEnabled(service string) (bool, error) {
 	args := []string{"is-enabled", service}
 	if err := exec.Command("systemctl", args...).Run(); err != nil {
 		switch v := err.(type) {