emit warning on no liveness probe defined for pods

This patch iterates through pod specs, listing specs with no liveness
probes set. Any replication controllers whose deployment is fulfilled by
a DeploymentConfig are ignored.

**Example**
```
$ oc create -f pkg/api/graph/test/simple-deployment
deploymentconfig "simple-deployment" created

$ oc get all
NAME                   REVISION   DESIRED   CURRENT   TRIGGERED BY
dc/simple-deployment   1          1         0         config

NAME                     DESIRED   CURRENT   READY     AGE
rc/simple-deployment-1   0         0         0         1m

NAME                            READY     STATUS              RESTARTS
AGE
po/simple-deployment-1-deploy   0/1       ContainerCreating   0
1m

$ oc status -v
In project test on server https://10.111.123.56:8443

dc/simple-deployment deploys docker.io/openshift/deployment-example:v1
  deployment #1 pending 26 seconds ago

Warnings:
  * pod/simple-deployment-1-deploy has no liveness probe to verify pods are still running.
    try: oc set probe pod/simple-deployment-1-deploy --liveness ...
  * dc/simple-deployment has no liveness probe to verify pods are still running.
    try: oc set probe dc/simple-deployment --liveness ...

View details with 'oc describe <resource>/<name>' or list everything with 'oc get all'.
```

Author: juanvallejo

pkg/api/kubegraph/analysis/podspec.go

@@ -8,11 +8,16 @@ import (
 	osgraph "github.com/openshift/origin/pkg/api/graph"
 	kubeedges "github.com/openshift/origin/pkg/api/kubegraph"
 	kubegraph "github.com/openshift/origin/pkg/api/kubegraph/nodes"
+	kubenodes "github.com/openshift/origin/pkg/api/kubegraph/nodes"
+	deploygraph "github.com/openshift/origin/pkg/deploy/graph"
+	deploynodes "github.com/openshift/origin/pkg/deploy/graph/nodes"
+	"k8s.io/kubernetes/pkg/util/sets"
 )
 
 const (
-	UnmountableSecretWarning = "UnmountableSecret"
-	MissingSecretWarning     = "MissingSecret"
+	UnmountableSecretWarning    = "UnmountableSecret"
+	MissingSecretWarning        = "MissingSecret"
+	MissingLivenessProbeWarning = "MissingLivenessProbe"
 )
 
 // FindUnmountableSecrets inspects all PodSpecs for any Secret reference that isn't listed as mountable by the referenced ServiceAccount
@@ -75,6 +80,65 @@ func FindMissingSecrets(g osgraph.Graph, f osgraph.Namer) []osgraph.Marker {
 	return markers
 }
 
+// FindMissingLivenessProbes inspects all PodSpecs for missing liveness probes and generates a list of non-duplicate markers
+func FindMissingLivenessProbes(g osgraph.Graph, f osgraph.Namer, setProbeCommand string) []osgraph.Marker {
+	markers := []osgraph.Marker{}
+	appendedNodes := sets.NewString()
+	ignoredNodes := findDeploymentEdgeKinds(g)
+
+	for _, uncastPodSpecNode := range g.NodesByKind(kubegraph.PodSpecNodeKind) {
+		podSpecNode := uncastPodSpecNode.(*kubegraph.PodSpecNode)
+		podsWithoutLivenessProbes := CheckForLivenessProbes(g, podSpecNode)
+
+		topLevelNode := osgraph.GetTopLevelContainerNode(g, podSpecNode)
+		topLevelString := f.ResourceName(topLevelNode)
+
+		// prevent duplicate markers
+		if appendedNodes.Has(topLevelString) {
+			continue
+		}
+
+		// ignore replication controllers owned by DeploymentConfigs
+		if isNodeInList(topLevelNode, ignoredNodes) {
+			continue
+		}
+
+		appendedNodes.Insert(topLevelString)
+		for _, node := range podsWithoutLivenessProbes {
+			markers = append(markers, osgraph.Marker{
+				Node:         podSpecNode,
+				RelatedNodes: []graph.Node{node},
+
+				Severity: osgraph.WarningSeverity,
+				Key:      MissingLivenessProbeWarning,
+				Message: fmt.Sprintf("%s has no liveness probe to verify pods are still running.",
+					topLevelString),
+				Suggestion: osgraph.Suggestion(fmt.Sprintf("%s %s --liveness ...", setProbeCommand, topLevelString)),
+			})
+		}
+	}
+
+	return markers
+}
+
+func CheckForLivenessProbes(g osgraph.Graph, podSpecNode *kubegraph.PodSpecNode) []*kubegraph.PodSpecNode {
+	noLivenessProbes := []*kubegraph.PodSpecNode{}
+
+	hasLivenessProbe := false
+	for _, container := range podSpecNode.PodSpec.Containers {
+		if container.LivenessProbe != nil {
+			hasLivenessProbe = true
+			break
+		}
+	}
+
+	if !hasLivenessProbe {
+		noLivenessProbes = append(noLivenessProbes, podSpecNode)
+	}
+
+	return noLivenessProbes
+}
+
 // CheckForUnmountableSecrets checks to be sure that all the referenced secrets are mountable (by service account)
 func CheckForUnmountableSecrets(g osgraph.Graph, podSpecNode *kubegraph.PodSpecNode) []*kubegraph.SecretNode {
 	saNodes := g.SuccessorNodesByNodeAndEdgeKind(podSpecNode, kubegraph.ServiceAccountNodeKind, kubeedges.ReferencedServiceAccountEdgeKind)
@@ -122,3 +186,23 @@ func CheckMissingMountedSecrets(g osgraph.Graph, podSpecNode *kubegraph.PodSpecN
 
 	return missingSecrets
 }
+
+// findDeploymentEdgeKinds returns all replication controller nodes
+// whose deployment is being fulfilled by a DeploymentConfig
+func findDeploymentEdgeKinds(g osgraph.Graph) []graph.Node {
+	nodeFilter := osgraph.NodesOfKind(deploynodes.DeploymentConfigNodeKind)
+	edgeFilter := osgraph.EdgesOfKind(deploygraph.DeploymentEdgeKind)
+
+	subGraph := g.Subgraph(nodeFilter, edgeFilter)
+	return subGraph.NodesByKind(kubenodes.ReplicationControllerNodeKind)
+
+}
+
+func isNodeInList(node graph.Node, nodeList []graph.Node) bool {
+	for _, n := range nodeList {
+		if n == node {
+			return true
+		}
+	}
+	return false
+}

pkg/api/kubegraph/analysis/podspec_test.go

@@ -80,3 +80,23 @@ func TestUnmountableSecrets(t *testing.T) {
 		t.Errorf("expected %v, got %v", expectedSecret2, markers)
 	}
 }
+
+func TestMissingLivenessProbes(t *testing.T) {
+	g, _, err := osgraphtest.BuildGraph("../../../api/graph/test/simple-deployment.yaml")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	kubeedges.AddAllExposedPodEdges(g)
+
+	markers := FindMissingLivenessProbes(g, osgraph.DefaultNamer, "oc set probe")
+	if e, a := 1, len(markers); e != a {
+		t.Fatalf("expected %v, got %v", e, a)
+	}
+
+	actualDC := osgraph.GetTopLevelContainerNode(g, markers[0].Node)
+	expectedDC := g.Find(osgraph.UniqueName("DeploymentConfig|/simple-deployment"))
+	if e, a := expectedDC.ID(), actualDC.ID(); e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+}

pkg/cmd/cli/describe/projectstatus.go

@@ -383,6 +383,9 @@ func getMarkerScanners(logsCommandName, securityPolicyCommandFormat, setProbeCom
 		func(g osgraph.Graph, f osgraph.Namer) []osgraph.Marker {
 			return deployanalysis.FindDeploymentConfigReadinessWarnings(g, f, setProbeCommandName)
 		},
+		func(g osgraph.Graph, f osgraph.Namer) []osgraph.Marker {
+			return kubeanalysis.FindMissingLivenessProbes(g, f, setProbeCommandName)
+		},
 		routeanalysis.FindPortMappingIssues,
 		routeanalysis.FindMissingTLSTerminationType,
 		routeanalysis.FindPathBasedPassthroughRoutes,

test/cmd/set-liveness-probe.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+source "$(dirname "${BASH_SOURCE}")/../../hack/lib/init.sh"
+trap os::test::junit::reconcile_output EXIT
+
+# Cleanup cluster resources created by this test
+(
+  set +e
+  oc delete all,templates --all
+  exit 0
+) &>/dev/null
+
+
+os::test::junit::declare_suite_start "cmd/set-probe-liveness"
+# This test setting a liveness probe, without warning about replication controllers whose deployment depends on deployment configs
+os::cmd::expect_success_and_text 'oc create -f pkg/api/graph/test/simple-deployment.yaml' 'deploymentconfig "simple-deployment" created'
+os::cmd::expect_success_and_text 'oc status -v' 'dc/simple-deployment has no liveness probe'
+os::cmd::expect_success_and_not_text 'oc status -v' 'rc/simple-deployment-1 has no liveness probe'
+os::cmd::expect_success_and_text 'oc set probe dc/node --liveness --get-url=http://google.com:80' 'deploymentconfig "simple-deployment" updated'
+os::cmd::expect_success_and_not_text 'oc status -v' 'dc/simple-deployment has no liveness probe'
+echo "set-probe-liveness: ok"
+os::test::junit::declare_suite_end