fix:[#427] refuse to remove stack if in use

- add check for stack in use before removing subsystem
- add error message for in use stack in locales

cmd/stacks.go

@@ -488,6 +488,23 @@ func removeStack(cmd *cobra.Command, args []string) error {
 		return nil
 	}
 
+	subSystems, _ := core.ListSubsystemForStack(stackName)
+	if len(subSystems) > 0 {
+		cmdr.Error.Printfln(apx.Trans("stacks.rm.error.inUse"), len(subSystems))
+		table := core.CreateApxTable(os.Stdout)
+		table.SetHeader([]string{apx.Trans("subsystems.labels.name"), "Stack", apx.Trans("subsystems.labels.status"), "Pkgs"})
+		for _, subSystem := range subSystems {
+			table.Append([]string{
+				subSystem.Name,
+				subSystem.Stack.Name,
+				subSystem.Status,
+				fmt.Sprintf("%d", len(subSystem.Stack.Packages)),
+			})
+		}
+		table.Render()
+		return nil
+	}
+
 	force, _ := cmd.Flags().GetBool("force")
 
 	if !force {

core/subSystem.go

@@ -308,6 +308,47 @@ func ListSubSystems(includeManaged bool, includeRootFull bool) ([]*SubSystem, er
 	return subsystems, nil
 }
 
+// ListSubsystemForStack returns a list of subsystems for the specified stack.
+func ListSubsystemForStack(stackName string) ([]*SubSystem, error) {
+	dbox, err := NewDbox()
+	if err != nil {
+		return nil, err
+	}
+
+	containers, err := dbox.ListContainers(true)
+	if err != nil {
+		return nil, err
+	}
+
+	subsystems := []*SubSystem{}
+	for _, container := range containers {
+		if _, ok := container.Labels["name"]; !ok {
+			continue
+		}
+
+		stack, err := LoadStack(stackName)
+		if err != nil {
+			log.Printf("Error loading stack %s: %s", stackName, err)
+			continue
+		}
+
+		internalName := genInternalName(container.Labels["name"])
+		subsystem := &SubSystem{
+			InternalName:     internalName,
+			Name:             container.Labels["name"],
+			Stack:            stack,
+			Status:           container.Status,
+			ExportedPrograms: findExported(internalName, container.Labels["name"]),
+		}
+
+		if subsystem.Stack.Name == stack.Name {
+			subsystems = append(subsystems, subsystem)
+		}
+	}
+
+	return subsystems, nil
+}
+
 func (s *SubSystem) Exec(captureOutput, detachedMode bool, args ...string) (string, error) {
 	dbox, err := NewDbox()
 	if err != nil {

locales/en.yml

@@ -295,6 +295,7 @@ stacks:
     description: "Remove the specified stack."
     error:
       noName: "No name specified."
+      inUse: "The stack is used in %d subsystems:"
     info:
       askConfirmation: "Are you sure you want to remove '%s'?"
       success: "Removed stack '%s'."