Turn 409 into 500 Try Again Later when using generateName

If a client says they want the name to be generated, a 409 is
not appropriate (since they didn't specify a name). Instead, we
should return the next most appropriate error, which is a 5xx
error indicating the request failed but the client *should* try
again.  Since there is no 5xx error that exactly fits this purpose,
use 500 with StatusReasonTryAgainLater set.

This commit does not implement client retry on TryAgainLater, but
clients should retry up to a certain number of times.

pkg/registry/registrytest/controller.go

@@ -17,6 +17,8 @@ limitations under the License.
 package registrytest
 
 import (
+	"sync"
+
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/watch"
@@ -26,6 +28,13 @@ import (
 type ControllerRegistry struct {
 	Err         error
 	Controllers *api.ReplicationControllerList
+	sync.Mutex
+}
+
+func (r *ControllerRegistry) SetError(err error) {
+	r.Lock()
+	defer r.Unlock()
+	r.Err = err
 }
 
 func (r *ControllerRegistry) ListControllers(ctx api.Context) (*api.ReplicationControllerList, error) {
@@ -37,6 +46,8 @@ func (r *ControllerRegistry) GetController(ctx api.Context, ID string) (*api.Rep
 }
 
 func (r *ControllerRegistry) CreateController(ctx api.Context, controller *api.ReplicationController) error {
+	r.Lock()
+	defer r.Unlock()
 	return r.Err
 }
 

pkg/registry/registrytest/minion.go

@@ -52,6 +52,12 @@ func NewMinionRegistry(minions []string, nodeResources api.NodeResources) *Minio
 	}
 }
 
+func (r *MinionRegistry) SetError(err error) {
+	r.Lock()
+	defer r.Unlock()
+	r.Err = err
+}
+
 func (r *MinionRegistry) ListMinions(ctx api.Context) (*api.NodeList, error) {
 	r.Lock()
 	defer r.Unlock()

pkg/registry/registrytest/pod.go

@@ -40,6 +40,12 @@ func NewPodRegistry(pods *api.PodList) *PodRegistry {
 	}
 }
 
+func (r *PodRegistry) SetError(err error) {
+	r.Lock()
+	defer r.Unlock()
+	r.Err = err
+}
+
 func (r *PodRegistry) ListPodsPredicate(ctx api.Context, filter func(*api.Pod) bool) (*api.PodList, error) {
 	r.Lock()
 	defer r.Unlock()

pkg/registry/registrytest/service.go

@@ -41,6 +41,12 @@ type ServiceRegistry struct {
 	UpdatedID string
 }
 
+func (r *ServiceRegistry) SetError(err error) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.Err = err
+}
+
 func (r *ServiceRegistry) ListServices(ctx api.Context) (*api.ServiceList, error) {
 	r.mu.Lock()
 	defer r.mu.Unlock()