From f729d748acc417ce246cab22d36bb399f46375b4 Mon Sep 17 00:00:00 2001
From: Dawn Chen <dawnchen@google.com>
Date: Fri, 14 Nov 2014 14:20:29 -0800
Subject: [PATCH] If the image with :latest tag specified in Spec, kubelet
 should try to pull the latest one even the policy is PullIfNotPresent.

---
 pkg/kubelet/dockertools/docker.go | 10 ++++++++++
 pkg/kubelet/kubelet.go            |  4 +++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/pkg/kubelet/dockertools/docker.go b/pkg/kubelet/dockertools/docker.go
index 544f6648f1a..481ee7096e9 100644
--- a/pkg/kubelet/dockertools/docker.go
+++ b/pkg/kubelet/dockertools/docker.go
@@ -247,6 +247,16 @@ func (p dockerPuller) IsImagePresent(name string) (bool, error) {
 	return false, err
 }
 
+// RequireLatestImage returns if the user wants the latest image
+func RequireLatestImage(name string) bool {
+	_, tag := parseImageName(name)
+
+	if tag == "latest" {
+		return true
+	}
+	return false
+}
+
 func (p throttledDockerPuller) IsImagePresent(name string) (bool, error) {
 	return p.puller.IsImagePresent(name)
 }
diff --git a/pkg/kubelet/kubelet.go b/pkg/kubelet/kubelet.go
index 3d2819bf690..cafd81a7d80 100644
--- a/pkg/kubelet/kubelet.go
+++ b/pkg/kubelet/kubelet.go
@@ -714,11 +714,13 @@ func (kl *Kubelet) syncPod(pod *api.BoundPod, dockerContainers dockertools.Docke
 		glog.V(3).Infof("Container with name %s--%s--%s doesn't exist, creating %#v", podFullName, uuid, container.Name, container)
 		if !api.IsPullNever(container.ImagePullPolicy) {
 			present, err := kl.dockerPuller.IsImagePresent(container.Image)
+			latest := dockertools.RequireLatestImage(container.Image)
 			if err != nil {
 				glog.Errorf("Failed to inspect image: %s: %#v skipping pod %s container %s", container.Image, err, podFullName, container.Name)
 				continue
 			}
-			if api.IsPullAlways(container.ImagePullPolicy) || !present {
+			if api.IsPullAlways(container.ImagePullPolicy) ||
+				(api.IsPullIfNotPresent(container.ImagePullPolicy) && (!present || latest)) {
 				if err := kl.dockerPuller.Pull(container.Image); err != nil {
 					glog.Errorf("Failed to pull image %s: %v skipping pod %s container %s.", container.Image, err, podFullName, container.Name)
 					continue