Merge pull request #30895 from mwielgus/rs-raporter

Automatic merge from submit-queue

Federated replica set pod analyser

A helper function that analyses a list of pods and checks how many of them (per cluster) are running or are unschedulable. 

This function should be replaced by a smarter/more effective informer that would count these values on the fly. Unfortunately this needs the ownerRef feature which may not be ready/enabled in 1.4. 

WIP because tests are not there yet. Will be added in the evening (PL time). 

Ref: #29741

cc: @quinton-hoole @jianhuiz @kubernetes/sig-cluster-federation

federation/pkg/federation-controller/replicaset/pod_helper.go

@@ -0,0 +1,92 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+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 replicaset
+
+import (
+	"fmt"
+	"time"
+
+	"k8s.io/kubernetes/federation/pkg/federation-controller/util"
+	api "k8s.io/kubernetes/pkg/api"
+	unversioned "k8s.io/kubernetes/pkg/api/unversioned"
+	api_v1 "k8s.io/kubernetes/pkg/api/v1"
+	"k8s.io/kubernetes/pkg/apis/extensions/v1beta1"
+	"k8s.io/kubernetes/pkg/labels"
+)
+
+type PodAnalysisResult struct {
+	// Total number of pods created.
+	Total int
+	// Number of pods that are running and ready.
+	RunningAndReady int
+	// Number of pods that have been in unschedulable state for UnshedulableThreshold seconds.
+	Unschedulable int
+
+	// TODO: Handle other scenarios like pod waiting too long for scheduler etc.
+}
+
+const (
+	// TODO: make it configurable
+	UnschedulableThreshold = 60 * time.Second
+)
+
+// A function that calculates how many pods from the list are in one of
+// the meaningful (from the replica set perspective) states. This function is
+// a temporary workaround against the current lack of ownerRef in pods.
+func AnalysePods(replicaSet *v1beta1.ReplicaSet, allPods []util.FederatedObject, currentTime time.Time) (map[string]PodAnalysisResult, error) {
+	selector, err := labelSelectorAsSelector(replicaSet.Spec.Selector)
+	if err != nil {
+		return nil, fmt.Errorf("invalid selector: %v", err)
+	}
+	result := make(map[string]PodAnalysisResult)
+
+	for _, fedObject := range allPods {
+		pod, isPod := fedObject.Object.(*api_v1.Pod)
+		if !isPod {
+			return nil, fmt.Errorf("invalid arg content - not a *pod")
+		}
+		if !selector.Empty() && selector.Matches(labels.Set(pod.Labels)) {
+			status := result[fedObject.ClusterName]
+			status.Total++
+			for _, condition := range pod.Status.Conditions {
+				if pod.Status.Phase == api_v1.PodRunning {
+					if condition.Type == api_v1.PodReady {
+						status.RunningAndReady++
+					}
+				} else {
+					if condition.Type == api_v1.PodScheduled &&
+						condition.Status == api_v1.ConditionFalse &&
+						condition.Reason == "Unschedulable" &&
+						condition.LastTransitionTime.Add(UnschedulableThreshold).Before(currentTime) {
+
+						status.Unschedulable++
+					}
+				}
+			}
+			result[fedObject.ClusterName] = status
+		}
+	}
+	return result, nil
+}
+
+func labelSelectorAsSelector(ps *v1beta1.LabelSelector) (labels.Selector, error) {
+	unversionedSelector := unversioned.LabelSelector{}
+	if err := api.Scheme.Convert(ps, &unversionedSelector, nil); err != nil {
+		return nil, err
+	}
+	return unversioned.LabelSelectorAsSelector(&unversionedSelector)
+}

federation/pkg/federation-controller/replicaset/pod_helper_test.go

@@ -0,0 +1,119 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+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 replicaset
+
+import (
+	"testing"
+	"time"
+
+	"k8s.io/kubernetes/federation/pkg/federation-controller/util"
+	"k8s.io/kubernetes/pkg/api/unversioned"
+	api_v1 "k8s.io/kubernetes/pkg/api/v1"
+	"k8s.io/kubernetes/pkg/apis/extensions/v1beta1"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAnalyze(t *testing.T) {
+	now := time.Now()
+	replicaSet := newReplicaSet(map[string]string{"A": "B"})
+	replicaSet2 := newReplicaSet(map[string]string{"C": "D"})
+	podRunning := newPod("p1", replicaSet,
+		api_v1.PodStatus{
+			Phase: api_v1.PodRunning,
+			Conditions: []api_v1.PodCondition{
+				{
+					Type:   api_v1.PodReady,
+					Status: api_v1.ConditionTrue,
+				},
+			},
+		})
+	podUnschedulable := newPod("pU", replicaSet,
+		api_v1.PodStatus{
+			Phase: api_v1.PodPending,
+			Conditions: []api_v1.PodCondition{
+				{
+					Type:               api_v1.PodScheduled,
+					Status:             api_v1.ConditionFalse,
+					Reason:             "Unschedulable",
+					LastTransitionTime: unversioned.Time{Time: now.Add(-10 * time.Minute)},
+				},
+			},
+		})
+	podOther := newPod("pO", replicaSet,
+		api_v1.PodStatus{
+			Phase:      api_v1.PodPending,
+			Conditions: []api_v1.PodCondition{},
+		})
+	podOtherRS := newPod("pO", replicaSet2,
+		api_v1.PodStatus{
+			Phase:      api_v1.PodPending,
+			Conditions: []api_v1.PodCondition{},
+		})
+
+	federatedObjects := []util.FederatedObject{
+		{ClusterName: "c1", Object: podRunning},
+		{ClusterName: "c1", Object: podRunning},
+		{ClusterName: "c1", Object: podRunning},
+		{ClusterName: "c1", Object: podUnschedulable},
+		{ClusterName: "c1", Object: podUnschedulable},
+		{ClusterName: "c2", Object: podOther},
+		{ClusterName: "c2", Object: podOtherRS},
+	}
+
+	raport, err := AnalysePods(replicaSet, federatedObjects, now)
+	assert.NoError(t, err)
+	assert.Equal(t, 2, len(raport))
+	c1Raport := raport["c1"]
+	c2Raport := raport["c2"]
+	assert.Equal(t, PodAnalysisResult{
+		Total:           5,
+		RunningAndReady: 3,
+		Unschedulable:   2,
+	}, c1Raport)
+	assert.Equal(t, PodAnalysisResult{
+		Total:           1,
+		RunningAndReady: 0,
+		Unschedulable:   0,
+	}, c2Raport)
+}
+
+func newReplicaSet(selectorMap map[string]string) *v1beta1.ReplicaSet {
+	replicas := int32(3)
+	rs := &v1beta1.ReplicaSet{
+		ObjectMeta: api_v1.ObjectMeta{
+			Name:      "foobar",
+			Namespace: "default",
+		},
+		Spec: v1beta1.ReplicaSetSpec{
+			Replicas: &replicas,
+			Selector: &v1beta1.LabelSelector{MatchLabels: selectorMap},
+		},
+	}
+	return rs
+}
+
+func newPod(name string, rs *v1beta1.ReplicaSet, status api_v1.PodStatus) *api_v1.Pod {
+	return &api_v1.Pod{
+		ObjectMeta: api_v1.ObjectMeta{
+			Name:      name,
+			Namespace: rs.Namespace,
+			Labels:    rs.Spec.Selector.MatchLabels,
+		},
+		Status: status,
+	}
+}