feat(script): Persist transient unit name to disk

cloudinit/systemd.go

@@ -20,7 +20,7 @@ func StartUnit(name string) error {
 	return err
 }
 
-func ExecuteScript(scriptPath string) error {
+func ExecuteScript(scriptPath string) (string, error) {
 	props := []dbus.Property{
 		dbus.PropDescription("Unit generated and executed by coreos-cloudinit on behalf of user"),
 		dbus.PropExecStart([]string{"/bin/bash", scriptPath}, false),
@@ -33,9 +33,9 @@ func ExecuteScript(scriptPath string) error {
 
 	conn, err := dbus.New()
 	if err != nil {
-		return err
+		return "", err
 	}
 
 	_, err = conn.StartTransientUnit(name, "replace", props...)
-	return err
+	return name, err
 }

cloudinit/workspace.go

@@ -59,3 +59,8 @@ func PersistScriptInWorkspace(script Script, workspace string) (string, error) {
 
 	return f.Name(), nil
 }
+
+func PersistScriptUnitNameInWorkspace(name string, workspace string) error {
+	unitPath := path.Join(workspace, "scripts", "unit-name")
+	return ioutil.WriteFile(unitPath, []byte(name), 644)
+}

coreos-cloudinit.go

@@ -75,7 +75,9 @@ func main() {
 		var path string
 		path, err = cloudinit.PersistScriptInWorkspace(t, workspace)
 		if err == nil {
-			err = cloudinit.ExecuteScript(path)
+			var name string
+			name, err = cloudinit.ExecuteScript(path)
+			cloudinit.PersistScriptUnitNameInWorkspace(name, workspace)
 		}
 	}