Add K0s utility functions and cleanup (#546)

* adding utils components to handle k0s

Signed-off-by: William Rizzo <william.rizzo@gmail.com>

* Adding systemd units for k0s

Signed-off-by: William Rizzo <william.rizzo@gmail.com>

* fix k0s services

Signed-off-by: William Rizzo <william.rizzo@gmail.com>

* Remove shutdown now, it will be addressed later

see kairos-io/kairos#3126

Signed-off-by: Mauro Morales <contact@mauromorales.com>

* Revert FindCommand changes

This function is not specific for k3s hence also not for k0s

Signed-off-by: Mauro Morales <contact@mauromorales.com>

* Remove utils.Version()

For versioning we now use the versioneer package also in this repo. I
couldn't find any instance of components depending on utils.Version() so
I think it's safe to remove

Signed-off-by: Mauro Morales <contact@mauromorales.com>

* Revert changes to the go.mod & go.sum files

Signed-off-by: Mauro Morales <contact@mauromorales.com>

* Revert "Remove utils.Version()"

This reverts commit c5f48d96d3.

* Remove utils.Version()

This is not being used anymore, use Versioneer package instead

Signed-off-by: Mauro Morales <contact@mauromorales.com>

* Update machine/machine.go

Co-authored-by: Dimitris Karakasilis <dimitris@karakasilis.me>

---------

Signed-off-by: William Rizzo <william.rizzo@gmail.com>
Signed-off-by: Mauro Morales <contact@mauromorales.com>
Co-authored-by: Mauro Morales <contact@mauromorales.com>
Co-authored-by: Dimitris Karakasilis <dimitris@karakasilis.me>

machine/machine.go

@@ -107,6 +107,37 @@ func K3sEnvUnit(unit string) string {
 	return fmt.Sprintf("/etc/sysconfig/%s", unit)
 }
 
+func K0s() (Service, error) {
+	if utils.IsOpenRCBased() {
+		return openrc.NewService(
+			openrc.WithName("k0scontroller"),
+		)
+	}
+
+	return systemd.NewService(
+		systemd.WithName("k0scontroller"),
+	)
+}
+
+func K0sWorker() (Service, error) {
+	if utils.IsOpenRCBased() {
+		return openrc.NewService(
+			openrc.WithName("k0sworker"),
+		)
+	}
+
+	return systemd.NewService(
+		systemd.WithName("k0sworker"),
+	)
+}
+
+func K0sEnvUnit(unit string) string {
+	if utils.IsOpenRCBased() {
+		return fmt.Sprintf("/etc/k0s/%s.env", unit)
+	}
+
+	return fmt.Sprintf("/etc/sysconfig/%s", unit)
+}
 func UUID() string {
 	if os.Getenv("UUID") != "" {
 		return os.Getenv("UUID")

utils/utils.go

@@ -135,8 +135,21 @@ func K3sBin() string {
 	return ""
 }
 
+func K0sBin() string {
+	for _, p := range []string{"/usr/bin/k0s", "/usr/local/bin/k0s"} {
+		if _, err := os.Stat(p); err == nil {
+			return p
+		}
+	}
+
+	return ""
+}
+
 func WriteEnv(envFile string, config map[string]string) error {
-	content, _ := os.ReadFile(envFile)
+	content, err := os.ReadFile(envFile)
+	if err != nil && !os.IsNotExist(err) {
+		return err
+	}
 	env, _ := godotenv.Unmarshal(string(content))
 
 	for key, val := range config {
@@ -157,18 +170,14 @@ func Flavor() string {
 
 // GetInit Return the init system used by the OS
 func GetInit() string {
-	for _, file := range []string{"/run/systemd/system", "/sbin/systemctl", "/usr/bin/systemctl", "/usr/sbin/systemctl", "/usr/bin/systemctl"} {
-		_, err := os.Stat(file)
-		// Found systemd
-		if err == nil {
+	for _, file := range []string{"/run/systemd/system", "/sbin/systemctl", "/usr/bin/systemctl", "/usr/sbin/systemctl"} {
+		if _, err := os.Stat(file); err == nil {
 			return systemd
 		}
 	}
 
 	for _, file := range []string{"/sbin/openrc", "/usr/sbin/openrc", "/bin/openrc", "/usr/bin/openrc"} {
-		_, err := os.Stat(file)
-		// Found openrc
-		if err == nil {
+		if _, err := os.Stat(file); err == nil {
 			return openrc
 		}
 	}
@@ -262,16 +271,6 @@ func PowerOFF() {
 	}
 }
 
-func Version() string {
-	v, err := OSRelease("VERSION")
-	if err != nil {
-		return ""
-	}
-	v = strings.ReplaceAll(v, "+k3s1-Kairos", "-")
-	v = strings.ReplaceAll(v, "+k3s-Kairos", "-")
-	return strings.ReplaceAll(v, "Kairos", "")
-}
-
 func ListToOutput(rels []string, output string) []string {
 	switch strings.ToLower(output) {
 	case "yaml":