cmd, pkg/podman: Turn Image into an interface

src/cmd/completion.go

@@ -150,12 +150,10 @@ func completionImageNames(cmd *cobra.Command, _ []string, _ string) ([]string, c
 	if images, err := podman.GetImages(true); err != nil {
 		logrus.Debugf("Getting all images failed: %s", err)
 	} else {
-		for _, image := range images {
-			if len(image.Names) != 1 {
-				panic("cannot complete unflattened Image")
-			}
-
-			imageNames = append(imageNames, image.Names[0])
+		for images.Next() {
+			image := images.Get()
+			name := image.Name()
+			imageNames = append(imageNames, name)
 		}
 	}
 
@@ -170,15 +168,12 @@ func completionImageNamesFiltered(_ *cobra.Command, args []string, _ string) ([]
 	if images, err := podman.GetImages(true); err != nil {
 		logrus.Debugf("Getting all images failed: %s", err)
 	} else {
-		for _, image := range images {
+		for images.Next() {
+			image := images.Get()
+			name := image.Name()
 			skip := false
-
-			if len(image.Names) != 1 {
-				panic("cannot complete unflattened Image")
-			}
-
 			for _, arg := range args {
-				if arg == image.Names[0] {
+				if arg == name {
 					skip = true
 					break
 				}
@@ -188,7 +183,7 @@ func completionImageNamesFiltered(_ *cobra.Command, args []string, _ string) ([]
 				continue
 			}
 
-			imageNames = append(imageNames, image.Names[0])
+			imageNames = append(imageNames, name)
 		}
 	}
 

src/cmd/list.go

@@ -81,7 +81,7 @@ func list(cmd *cobra.Command, args []string) error {
 		lsImages = false
 	}
 
-	var images []podman.Image
+	var images *podman.Images
 	var containers *podman.Containers
 	var err error
 
@@ -130,26 +130,26 @@ func listHelp(cmd *cobra.Command, args []string) {
 	}
 }
 
-func listOutput(images []podman.Image, containers *podman.Containers) {
-	if len(images) != 0 {
+func listOutput(images *podman.Images, containers *podman.Containers) {
+	if images.Len() != 0 {
 		writer := tabwriter.NewWriter(os.Stdout, 0, 0, 2, ' ', 0)
 		fmt.Fprintf(writer, "%s\t%s\t%s\n", "IMAGE ID", "IMAGE NAME", "CREATED")
 
-		for _, image := range images {
-			if len(image.Names) != 1 {
-				panic("cannot list unflattened Image")
-			}
+		for images.Next() {
+			image := images.Get()
+			created := image.Created()
+			name := image.Name()
+
+			id := image.ID()
+			shortID := utils.ShortID(id)
 
-			fmt.Fprintf(writer, "%s\t%s\t%s\n",
-				utils.ShortID(image.ID),
-				image.Names[0],
-				image.Created)
+			fmt.Fprintf(writer, "%s\t%s\t%s\n", shortID, name, created)
 		}
 
 		writer.Flush()
 	}
 
-	if len(images) != 0 && containers.Len() != 0 {
+	if images.Len() != 0 && containers.Len() != 0 {
 		fmt.Println()
 	}
 
@@ -199,11 +199,15 @@ func listOutput(images []podman.Image, containers *podman.Containers) {
 			}
 
 			created := container.Created()
-			id := container.ID()
 			image := container.Image()
 			name := container.Name()
+
+			id := container.ID()
+			shortID := utils.ShortID(id)
+
 			status := container.Status()
-			fmt.Fprintf(writer, "%s\t%s\t%s\t%s\t%s", utils.ShortID(id), name, created, status, image)
+
+			fmt.Fprintf(writer, "%s\t%s\t%s\t%s\t%s", shortID, name, created, status, image)
 
 			if term.IsTerminal(os.Stdout) {
 				fmt.Fprintf(writer, "%s", resetColor)

src/cmd/rmi.go

@@ -76,8 +76,9 @@ func rmi(cmd *cobra.Command, args []string) error {
 			return errors.New("failed to get images")
 		}
 
-		for _, image := range toolboxImages {
-			imageID := image.ID
+		for toolboxImages.Next() {
+			image := toolboxImages.Get()
+			imageID := image.ID()
 			if err := podman.RemoveImage(imageID, rmiFlags.forceDelete); err != nil {
 				fmt.Fprintf(os.Stderr, "Error: %s\n", err)
 				continue

src/meson.build

@@ -23,6 +23,8 @@ sources = files(
   'pkg/nvidia/nvidia.go',
   'pkg/podman/container.go',
   'pkg/podman/errors.go',
+  'pkg/podman/image.go',
+  'pkg/podman/imageImages_test.go',
   'pkg/podman/podman.go',
   'pkg/podman/containerInspect_test.go',
   'pkg/shell/shell.go',

src/pkg/podman/image.go

@@ -0,0 +1,206 @@
+/*
+ * Copyright © 2025 – 2026 Red Hat Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package podman
+
+import (
+	"encoding/json"
+
+	"github.com/containers/toolbox/pkg/utils"
+)
+
+type Image interface {
+	Created() string
+	ID() string
+	IsToolbx() bool
+	Labels() map[string]string
+	Name() string
+	Names() []string
+}
+
+type Images struct {
+	data []imageImages
+	i    int
+}
+
+type imageImages struct {
+	created string
+	id      string
+	labels  map[string]string
+	names   []string
+}
+
+type imageSlice []imageImages
+
+func (images *Images) Get() Image {
+	if images == nil {
+		panic("called Images.Get() on a nil Images")
+	}
+
+	if images.i < 1 {
+		panic("called Images.Get() without calling Images.Next()")
+	}
+
+	image := &images.data[images.i-1]
+	return image
+}
+
+func (images *Images) Len() int {
+	if images == nil {
+		return 0
+	}
+
+	return len(images.data)
+}
+
+func (images *Images) Next() bool {
+	if images == nil {
+		return false
+	}
+
+	available := images.i < len(images.data)
+	if available {
+		images.i++
+	}
+
+	return available
+}
+
+func (images *Images) Reset() {
+	if images == nil {
+		return
+	}
+
+	images.i = 0
+}
+
+func (image *imageImages) Created() string {
+	return image.created
+}
+
+func (image *imageImages) flattenNames(fillNameWithID bool) []imageImages {
+	var ret []imageImages
+
+	names := image.Names()
+	namesCount := len(names)
+	if namesCount == 0 {
+		flattenedImage := *image
+
+		if fillNameWithID {
+			id := image.ID()
+			shortID := utils.ShortID(id)
+			flattenedImage.names = []string{shortID}
+		} else {
+			flattenedImage.names = []string{"<none>"}
+		}
+
+		ret = []imageImages{flattenedImage}
+		return ret
+	}
+
+	ret = make([]imageImages, 0, namesCount)
+
+	for _, name := range names {
+		flattenedImage := *image
+		flattenedImage.names = []string{name}
+		ret = append(ret, flattenedImage)
+	}
+
+	return ret
+}
+
+func (image *imageImages) ID() string {
+	return image.id
+}
+
+func (image *imageImages) IsToolbx() bool {
+	return isToolbx(image.labels)
+}
+
+func (image *imageImages) Labels() map[string]string {
+	if image.labels == nil {
+		return nil
+	}
+
+	labelsCount := len(image.labels)
+	ret := make(map[string]string, labelsCount)
+	for label, value := range image.labels {
+		ret[label] = value
+	}
+
+	return ret
+}
+
+func (image *imageImages) Name() string {
+	if len(image.names) != 1 {
+		panic("cannot get name from unflattened Image")
+	}
+
+	return image.names[0]
+}
+
+func (image *imageImages) Names() []string {
+	if image.names == nil {
+		return nil
+	}
+
+	namesCount := len(image.names)
+	ret := make([]string, namesCount)
+	copy(ret, image.names)
+	return ret
+}
+
+func (image *imageImages) UnmarshalJSON(data []byte) error {
+	var raw struct {
+		Created interface{}
+		ID      string
+		Labels  map[string]string
+		Names   []string
+	}
+
+	if err := json.Unmarshal(data, &raw); err != nil {
+		return err
+	}
+
+	// Until Podman 2.0.x the field 'Created' held a human-readable string in
+	// format "5 minutes ago". Since Podman 2.1 the field holds an integer with
+	// Unix time. Go interprets numbers in JSON as float64.
+	switch value := raw.Created.(type) {
+	case string:
+		image.created = value
+	case float64:
+		image.created = utils.HumanDuration(int64(value))
+	}
+
+	image.id = raw.ID
+	image.labels = raw.Labels
+	image.names = raw.Names
+	return nil
+}
+
+func (images imageSlice) Len() int {
+	return len(images)
+}
+
+func (images imageSlice) Less(i, j int) bool {
+	nameI := images[i].Name()
+	nameJ := images[j].Name()
+	return nameI < nameJ
+}
+
+func (images imageSlice) Swap(i, j int) {
+	images[i], images[j] = images[j], images[i]
+}