Add kpod tag command

Add one or more tags to an image

Signed-off-by: Ryan Cole <rcyoalne@gmail.com>

cmd/kpod/tag.go

@@ -0,0 +1,73 @@
+package main
+
+import (
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/storage"
+	"github.com/pkg/errors"
+	"github.com/urfave/cli"
+)
+
+var (
+	tagDescription = "Adds one or more additional names to locally-stored image"
+	tagCommand     = cli.Command{
+		Name:        "tag",
+		Usage:       "Add an additional name to a local image",
+		Description: tagDescription,
+		Action:      tagCmd,
+		ArgsUsage:   "IMAGE-NAME [IMAGE-NAME ...]",
+	}
+)
+
+func tagCmd(c *cli.Context) error {
+	args := c.Args()
+	if len(args) < 2 {
+		return errors.Errorf("image name and at least one new name must be specified")
+	}
+	store, err := getStore(c)
+	if err != nil {
+		return err
+	}
+	img, err := findImage(store, args[0])
+	if err != nil {
+		return err
+	}
+	if img == nil {
+		return errors.New("null image")
+	}
+	err = addImageNames(store, img, args[1:])
+	if err != nil {
+		return errors.Wrapf(err, "error adding names %v to image %q", args[1:], args[0])
+	}
+	return nil
+}
+
+func addImageNames(store storage.Store, image *storage.Image, addNames []string) error {
+	// Add tags to the names if applicable
+	names, err := expandedTags(addNames)
+	if err != nil {
+		return err
+	}
+	err = store.SetNames(image.ID, append(image.Names, names...))
+	if err != nil {
+		return errors.Wrapf(err, "error adding names (%v) to image %q", names, image.ID)
+	}
+	return nil
+}
+
+func expandedTags(tags []string) ([]string, error) {
+	expandedNames := []string{}
+	for _, tag := range tags {
+		name, err := reference.ParseNormalizedNamed(tag)
+		if err != nil {
+			return nil, errors.Wrapf(err, "error parsing tag %q", name)
+		}
+
+		name = reference.TagNameOnly(name)
+		newTag := ""
+		if tagged, ok := name.(reference.NamedTagged); ok {
+			newTag = tagged.Tag()
+		}
+		expandedNames = append(expandedNames, name.Name()+":"+newTag)
+	}
+	return expandedNames, nil
+}