feat(compose): Introduce RemoveOrphans function

The removeOrphans function goes through all machines
linked to a project and removes the ones that are no
longer part of the compose file.

Signed-off-by: Luca Seritan <luca.seritan@gmail.com>

internal/cli/kraft/compose/utils/utils.go

@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright (c) 2024, Unikraft GmbH and The KraftKit Authors.
+// Licensed under the BSD-3-Clause License (the "License").
+// You may not use this file except in compliance with the License.
+
+package utils
+
+import (
+	"context"
+
+	"kraftkit.sh/compose"
+	"kraftkit.sh/internal/cli/kraft/remove"
+	"kraftkit.sh/log"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	composeapi "kraftkit.sh/api/compose/v1"
+	machineapi "kraftkit.sh/api/machine/v1alpha1"
+	mplatform "kraftkit.sh/machine/platform"
+)
+
+func RemoveOrphans(ctx context.Context, project *compose.Project) error {
+	composeController, err := compose.NewComposeProjectV1(ctx)
+	if err != nil {
+		return err
+	}
+
+	embeddedProject, err := composeController.Get(ctx, &composeapi.Compose{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: project.Name,
+		},
+	})
+	if err != nil {
+		return err
+	}
+
+	machineController, err := mplatform.NewMachineV1alpha1ServiceIterator(ctx)
+	if err != nil {
+		return err
+	}
+
+	machines, err := machineController.List(ctx, &machineapi.MachineList{})
+	if err != nil {
+		return err
+	}
+
+	orphanMachines := []string{}
+	for _, machine := range embeddedProject.Status.Machines {
+		isService := false
+		for _, service := range project.Services {
+			if service.Name == machine.Name {
+				isService = true
+				break
+			}
+		}
+
+		for _, m := range machines.Items {
+			if m.Name == machine.Name {
+				if !isService && m.Status.State == machineapi.MachineStateRunning {
+					orphanMachines = append(orphanMachines, machine.Name)
+				}
+			}
+		}
+	}
+
+	if len(orphanMachines) == 0 {
+		return nil
+	}
+
+	log.G(ctx).Info("removing orphan machines...")
+	removeOptions := remove.RemoveOptions{
+		Platform: "auto",
+	}
+
+	return removeOptions.Run(ctx, orphanMachines)
+}