new file mode 100644

@@ -0,0 +1,25 @@

+package lib

+

+import "net/url"

+

+// ImageTagOptions hold parameters to tag an image

+type ImageTagOptions struct {

+	ImageID        string

+	RepositoryName string

+	Tag            string

+	Force          bool

+}

+

+// ImageTag tags an image in the docker host

+func (cli *Client) ImageTag(options types.ImageTagOptions) error {

+	query := url.Values{}

+	query.Set("repo", options.RepositoryName)

+	query.Set("tag", options.Tag)

+	if options.Force {

+		query.Set("force", "1")

+	}

+

+	resp, err := cli.POST("/images/"+options.ImageID+"/tag", query, nil, nil)

+	ensureReaderClosed(resp)

+	return err

+}

@@ -2,9 +2,9 @@ package client

 import (

 	"errors"

-	"net/url"

 	"github.com/docker/distribution/reference"

+	"github.com/docker/docker/api/client/lib"

 	Cli "github.com/docker/docker/cli"

 	flag "github.com/docker/docker/pkg/mflag"

 	"github.com/docker/docker/registry"

@@ -20,7 +20,6 @@ func (cli *DockerCli) CmdTag(args ...string) error {

 	cmd.ParseFlags(args, true)

-	v := url.Values{}

 	ref, err := reference.ParseNamed(cmd.Arg(1))

 	if err != nil {

 		return err

@@ -41,15 +40,13 @@ func (cli *DockerCli) CmdTag(args ...string) error {

 	if err := registry.ValidateRepositoryName(ref); err != nil {

 		return err

 	}

-	v.Set("repo", ref.Name())

-	v.Set("tag", tag)

-	if *force {

-		v.Set("force", "1")

+	options := lib.ImageTagOptions{

+		ImageID:        cmd.Arg(0),

+		RepositoryName: ref.Name(),

+		Tag:            tag,

+		Force:          *force,

 	}

-	if _, _, err := readBody(cli.call("POST", "/images/"+cmd.Arg(0)+"/tag?"+v.Encode(), nil, nil)); err != nil {

-		return err

-	}

-	return nil

+	return cli.client.ImageTag(options)

 }