Refactor exec to make attach useful without a client.Config

The current executor structure is too dependent on client.Request
and client.Config. In order to do an attach from the server, it needs
to be possible to create an Executor from crypto/tls#TLSConfig and to
bypassing having a client.Request.

Changes:

* remotecommand.spdyExecutor - handles upgrading a request to SPDY and getting a connection
* remotecommand.NewAttach / New - moved to exec / portforward / attach since they handle requests
* Remove request.Upgrade() - it's too coupled to SPDY, and can live with the spdyExecutor
* Add request.VersionedParams(runtime.Object, runtime.ObjectConvertor) to handle object -> query transform

pkg/kubectl/cmd/portforward.go

@@ -17,6 +17,7 @@ limitations under the License.
 package cmd
 
 import (
+	"net/url"
 	"os"
 	"os/signal"
 
@@ -25,6 +26,7 @@ import (
 	"k8s.io/kubernetes/pkg/api"
 	client "k8s.io/kubernetes/pkg/client/unversioned"
 	"k8s.io/kubernetes/pkg/client/unversioned/portforward"
+	"k8s.io/kubernetes/pkg/client/unversioned/remotecommand"
 	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
 )
 
@@ -60,13 +62,17 @@ func NewCmdPortForward(f *cmdutil.Factory) *cobra.Command {
 }
 
 type portForwarder interface {
-	ForwardPorts(req *client.Request, config *client.Config, ports []string, stopChan <-chan struct{}) error
+	ForwardPorts(method string, url *url.URL, config *client.Config, ports []string, stopChan <-chan struct{}) error
 }
 
 type defaultPortForwarder struct{}
 
-func (*defaultPortForwarder) ForwardPorts(req *client.Request, config *client.Config, ports []string, stopChan <-chan struct{}) error {
-	fw, err := portforward.New(req, config, ports, stopChan)
+func (*defaultPortForwarder) ForwardPorts(method string, url *url.URL, config *client.Config, ports []string, stopChan <-chan struct{}) error {
+	dialer, err := remotecommand.NewExecutor(config, method, url)
+	if err != nil {
+		return err
+	}
+	fw, err := portforward.New(dialer, ports, stopChan)
 	if err != nil {
 		return err
 	}
@@ -130,5 +136,5 @@ func RunPortForward(f *cmdutil.Factory, cmd *cobra.Command, args []string, fw po
 		Name(pod.Name).
 		SubResource("portforward")
 
-	return fw.ForwardPorts(req, config, args, stopCh)
+	return fw.ForwardPorts("POST", req.URL(), config, args, stopCh)
 }