Return immediately when controllers/pods are committed

Add client waiting conditions.

pkg/client/conditions.go

@@ -0,0 +1,35 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package client
+
+import (
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/util/wait"
+)
+
+// ControllerHasDesiredReplicas returns a condition that will be true iff the desired replica count
+// for a controller's ReplicaSelector equals the Replicas count.
+func (c *Client) ControllerHasDesiredReplicas(controller api.ReplicationController) wait.ConditionFunc {
+	return func() (bool, error) {
+		pods, err := c.ListPods(labels.Set(controller.DesiredState.ReplicaSelector).AsSelector())
+		if err != nil {
+			return false, err
+		}
+		return len(pods.Items) == controller.DesiredState.Replicas, nil
+	}
+}