Add image tag command for existing local images

Author: chruffins

pkg/cmd/imagecmd.go

@@ -20,6 +20,7 @@ var imageCmd = cli.Command{
 		&imageCreateCmd,
 		&imageListCmd,
 		&imageGetCmd,
+		&imageTagCmd,
 		&imageDeleteCmd,
 	},
 	HideHelpCommand: true,
@@ -60,6 +61,14 @@ var imageGetCmd = cli.Command{
 	HideHelpCommand: true,
 }
 
+var imageTagCmd = cli.Command{
+	Name:            "tag",
+	Usage:           "Tag an existing local image without pulling or converting",
+	ArgsUsage:       "<source> <target>",
+	Action:          handleImageTag,
+	HideHelpCommand: true,
+}
+
 var imageDeleteCmd = cli.Command{
 	Name:            "delete",
 	Aliases:         []string{"rm"},
@@ -255,6 +264,49 @@ func handleImageGet(ctx context.Context, cmd *cli.Command) error {
 	return ShowJSON(os.Stdout, "image get", obj, format, transform)
 }
 
+// imageTagBody is the POST /images/{name}/tag request body, defined locally
+// until the generated SDK gains a typed method for the endpoint.
+type imageTagBody struct {
+	Name string `json:"name"`
+}
+
+func handleImageTag(ctx context.Context, cmd *cli.Command) error {
+	args := cmd.Args().Slice()
+	if len(args) < 2 {
+		return fmt.Errorf("source and target required\nUsage: hypeman image tag <source> <target>")
+	}
+	source, target := args[0], args[1]
+
+	client := hypeman.NewClient(getDefaultRequestOptions(cmd)...)
+
+	var opts []option.RequestOption
+	if cmd.Root().Bool("debug") {
+		opts = append(opts, debugMiddlewareOption)
+	}
+
+	path := fmt.Sprintf("images/%s/tag", url.PathEscape(source))
+	body := imageTagBody{Name: target}
+
+	format := cmd.Root().String("format")
+	transform := cmd.Root().String("transform")
+
+	if format != "auto" {
+		var res []byte
+		opts = append(opts, option.WithResponseBodyInto(&res))
+		if err := client.Post(ctx, path, body, nil, opts...); err != nil {
+			return err
+		}
+		return ShowJSON(os.Stdout, "image tag", gjson.ParseBytes(res), format, transform)
+	}
+
+	var img hypeman.Image
+	if err := client.Post(ctx, path, body, &img, opts...); err != nil {
+		return err
+	}
+	fmt.Println(img.Name)
+	return nil
+}
+
 func handleImageDelete(ctx context.Context, cmd *cli.Command) error {
 	args := cmd.Args().Slice()
 	if len(args) < 1 {

pkg/cmd/imagecmd_test.go

@@ -1,6 +1,11 @@
 package cmd
 
 import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -37,3 +42,32 @@ func TestPlatformOrDash(t *testing.T) {
 	assert.Equal(t, "linux/amd64", platformOrDash("linux/amd64"))
 	assert.Equal(t, "-", platformOrDash(""))
 }
+
+func TestImageTagCommand_RequiresSourceAndTarget(t *testing.T) {
+	err := Command.Run(context.Background(), []string{"hypeman", "image", "tag", "only-source"})
+	require.EqualError(t, err, "source and target required\nUsage: hypeman image tag <source> <target>")
+}
+
+func TestImageTagCommand_PostsToTagEndpoint(t *testing.T) {
+	var gotMethod, gotPath string
+	var gotBody []byte
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotMethod = r.Method
+		gotPath = r.URL.EscapedPath()
+		gotBody, _ = io.ReadAll(r.Body)
+		w.Header().Set("Content-Type", "application/json")
+		fmt.Fprint(w, `{"name":"registry.example.com/app:v1","digest":"sha256:abc","status":"ready","created_at":"2026-01-01T00:00:00Z"}`)
+	}))
+	defer srv.Close()
+
+	err := Command.Run(context.Background(), []string{
+		"hypeman", "--base-url", srv.URL,
+		"image", "tag",
+		"docker.io/library/alpine:latest", "registry.example.com/app:v1",
+	})
+	require.NoError(t, err)
+
+	assert.Equal(t, http.MethodPost, gotMethod)
+	assert.Equal(t, "/images/docker.io%2Flibrary%2Falpine:latest/tag", gotPath)
+	assert.JSONEq(t, `{"name":"registry.example.com/app:v1"}`, string(gotBody))
+}