Push flow

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

api/client/commands.go

@@ -43,6 +43,7 @@ import (
 	"github.com/docker/docker/registry"
 	"github.com/docker/docker/runconfig"
 	"github.com/docker/docker/utils"
+	"github.com/docker/libtrust"
 )
 
 const (
@@ -1215,6 +1216,26 @@ func (cli *DockerCli) CmdPush(args ...string) error {
 
 	v := url.Values{}
 	v.Set("tag", tag)
+
+	body, _, err := readBody(cli.call("GET", "/images/"+remote+"/manifest?"+v.Encode(), nil, false))
+	if err != nil {
+		return err
+	}
+
+	js, err := libtrust.NewJSONSignature(body)
+	if err != nil {
+		return err
+	}
+	err = js.Sign(cli.key)
+	if err != nil {
+		return err
+	}
+
+	signedBody, err := js.PrettySignature("signatures")
+	if err != nil {
+		return err
+	}
+
 	push := func(authConfig registry.AuthConfig) error {
 		buf, err := json.Marshal(authConfig)
 		if err != nil {
@@ -1224,7 +1245,7 @@ func (cli *DockerCli) CmdPush(args ...string) error {
 			base64.URLEncoding.EncodeToString(buf),
 		}
 
-		return cli.stream("POST", "/images/"+remote+"/push?"+v.Encode(), nil, cli.out, map[string][]string{
+		return cli.stream("POST", "/images/"+remote+"/push?"+v.Encode(), bytes.NewReader(signedBody), cli.out, map[string][]string{
 			"X-Registry-Auth": registryAuthHeader,
 		})
 	}