Custom sort function for InitContainersStatuses

pkg/kubelet/kubelet.go

@@ -3830,7 +3830,11 @@ func (kl *Kubelet) convertToAPIContainerStatuses(pod *api.Pod, podStatus *kubeco
 
 	// Sort the container statuses since clients of this interface expect the list
 	// of containers in a pod has a deterministic order.
-	sort.Sort(kubetypes.SortedContainerStatuses(containerStatuses))
+	if isInitContainer {
+		kubetypes.SortInitContainerStatuses(pod, containerStatuses)
+	} else {
+		sort.Sort(kubetypes.SortedContainerStatuses(containerStatuses))
+	}
 	return containerStatuses
 }
 

pkg/kubelet/status/manager.go

@@ -306,7 +306,7 @@ func (m *manager) updateStatusInternal(pod *api.Pod, status api.PodStatus, force
 		status.StartTime = &now
 	}
 
-	normalizeStatus(&status)
+	normalizeStatus(pod, &status)
 	// The intent here is to prevent concurrent updates to a pod's status from
 	// clobbering each other so the phase of a pod progresses monotonically.
 	if isCached && isStatusEqual(&cachedStatus.status, &status) && !forceUpdate {
@@ -484,7 +484,7 @@ func (m *manager) needsReconcile(uid types.UID, status api.PodStatus) bool {
 	if err != nil {
 		return false
 	}
-	normalizeStatus(&podStatus)
+	normalizeStatus(pod, &podStatus)
 
 	if isStatusEqual(&podStatus, &status) {
 		// If the status from the source is the same with the cached status,
@@ -504,7 +504,7 @@ func (m *manager) needsReconcile(uid types.UID, status api.PodStatus) bool {
 // In fact, the best way to solve this is to do it on api side. However for now, we normalize the status locally in
 // kubelet temporarily.
 // TODO(random-liu): Remove timestamp related logic after apiserver supports nanosecond or makes it consistent.
-func normalizeStatus(status *api.PodStatus) *api.PodStatus {
+func normalizeStatus(pod *api.Pod, status *api.PodStatus) *api.PodStatus {
 	normalizeTimeStamp := func(t *unversioned.Time) {
 		*t = t.Rfc3339Copy()
 	}
@@ -543,7 +543,7 @@ func normalizeStatus(status *api.PodStatus) *api.PodStatus {
 		normalizeContainerState(&cstatus.LastTerminationState)
 	}
 	// Sort the container statuses, so that the order won't affect the result of comparison
-	sort.Sort(kubetypes.SortedContainerStatuses(status.InitContainerStatuses))
+	kubetypes.SortInitContainerStatuses(pod, status.InitContainerStatuses)
 	return status
 }
 

pkg/kubelet/status/manager_test.go

@@ -452,6 +452,9 @@ func shuffle(statuses []api.ContainerStatus) []api.ContainerStatus {
 }
 
 func TestStatusEquality(t *testing.T) {
+	pod := api.Pod{
+		Spec: api.PodSpec{},
+	}
 	containerStatus := []api.ContainerStatus{}
 	for i := 0; i < 10; i++ {
 		s := api.ContainerStatus{
@@ -466,8 +469,8 @@ func TestStatusEquality(t *testing.T) {
 		oldPodStatus := api.PodStatus{
 			ContainerStatuses: shuffle(podStatus.ContainerStatuses),
 		}
-		normalizeStatus(&oldPodStatus)
-		normalizeStatus(&podStatus)
+		normalizeStatus(&pod, &oldPodStatus)
+		normalizeStatus(&pod, &podStatus)
 		if !isStatusEqual(&oldPodStatus, &podStatus) {
 			t.Fatalf("Order of container statuses should not affect normalized equality.")
 		}
@@ -498,7 +501,7 @@ func TestStaticPodStatus(t *testing.T) {
 
 	m.SetPodStatus(staticPod, status)
 	retrievedStatus := expectPodStatus(t, m, staticPod)
-	normalizeStatus(&status)
+	normalizeStatus(staticPod, &status)
 	assert.True(t, isStatusEqual(&status, &retrievedStatus), "Expected: %+v, Got: %+v", status, retrievedStatus)
 	retrievedStatus, _ = m.GetPodStatus(mirrorPod.UID)
 	assert.True(t, isStatusEqual(&status, &retrievedStatus), "Expected: %+v, Got: %+v", status, retrievedStatus)

pkg/kubelet/types/types.go

@@ -68,6 +68,22 @@ func (s SortedContainerStatuses) Less(i, j int) bool {
 	return s[i].Name < s[j].Name
 }
 
+// SortInitContainerStatuses ensures that statuses are in the order that their
+// init container appears in the pod spec
+func SortInitContainerStatuses(p *api.Pod, statuses []api.ContainerStatus) {
+	containers := p.Spec.InitContainers
+	current := 0
+	for _, container := range containers {
+		for j := current; j < len(statuses); j++ {
+			if container.Name == statuses[j].Name {
+				statuses[current], statuses[j] = statuses[j], statuses[current]
+				current++
+				break
+			}
+		}
+	}
+}
+
 // Reservation represents reserved resources for non-pod components.
 type Reservation struct {
 	// System represents resources reserved for non-kubernetes components.

pkg/kubelet/types/types_test.go

@@ -0,0 +1,64 @@
+/*
+Copyright 2016 The Kubernetes Authors 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 types
+
+import (
+	"reflect"
+	"testing"
+
+	"k8s.io/kubernetes/pkg/api"
+)
+
+func TestSortInitContainerStatuses(t *testing.T) {
+	pod := api.Pod{
+		Spec: api.PodSpec{},
+	}
+	var cases = []struct {
+		containers     []api.Container
+		statuses       []api.ContainerStatus
+		sortedStatuses []api.ContainerStatus
+	}{
+		{
+			containers:     []api.Container{{Name: "first"}, {Name: "second"}, {Name: "third"}, {Name: "fourth"}},
+			statuses:       []api.ContainerStatus{{Name: "first"}, {Name: "second"}, {Name: "third"}, {Name: "fourth"}},
+			sortedStatuses: []api.ContainerStatus{{Name: "first"}, {Name: "second"}, {Name: "third"}, {Name: "fourth"}},
+		},
+		{
+			containers:     []api.Container{{Name: "first"}, {Name: "second"}, {Name: "third"}, {Name: "fourth"}},
+			statuses:       []api.ContainerStatus{{Name: "second"}, {Name: "first"}, {Name: "fourth"}, {Name: "third"}},
+			sortedStatuses: []api.ContainerStatus{{Name: "first"}, {Name: "second"}, {Name: "third"}, {Name: "fourth"}},
+		},
+		{
+			containers:     []api.Container{{Name: "first"}, {Name: "second"}, {Name: "third"}, {Name: "fourth"}},
+			statuses:       []api.ContainerStatus{{Name: "fourth"}, {Name: "first"}},
+			sortedStatuses: []api.ContainerStatus{{Name: "first"}, {Name: "fourth"}},
+		},
+		{
+			containers:     []api.Container{{Name: "first"}, {Name: "second"}, {Name: "third"}, {Name: "fourth"}},
+			statuses:       []api.ContainerStatus{{Name: "first"}, {Name: "third"}},
+			sortedStatuses: []api.ContainerStatus{{Name: "first"}, {Name: "third"}},
+		},
+	}
+	for _, data := range cases {
+		pod.Spec.InitContainers = data.containers
+		SortInitContainerStatuses(&pod, data.statuses)
+		if !reflect.DeepEqual(data.statuses, data.sortedStatuses) {
+			t.Errorf("SortInitContainerStatuses result wrong:\nContainers order: %v\nExpected order: %v\nReturne order: %v",
+				data.containers, data.sortedStatuses, data.statuses)
+		}
+	}
+}