Mark ephemeral pods created as part of kanister functions with JobID label

pkg/function/kube_task.go

@@ -16,6 +16,7 @@ package function
 
 import (
 	"context"
+	"path"
 	"time"
 
 	"github.com/pkg/errors"
@@ -33,7 +34,9 @@ import (
 )
 
 const (
-	jobPrefix = "kanister-job-"
+	jobPrefix   = "kanister-job-"
+	jobIDSuffix = "JobID"
+
 	// KubeTaskFuncName gives the function name
 	KubeTaskFuncName       = "KubeTask"
 	KubeTaskNamespaceArg   = "namespace"
@@ -64,7 +67,8 @@ func kubeTask(ctx context.Context, cli kubernetes.Interface, namespace, image st
 		Command:      command,
 		PodOverride:  podOverride,
 	}
-
+	// Mark labels to pods with prefix `kanister.io`. Add the jobID as reference to the origin for the pod.
+	kube.AddLabelsToPodOptionsFromContext(ctx, options, path.Join(consts.LabelPrefix, jobIDSuffix))
 	pr := kube.NewPodRunner(cli, options)
 	podFunc := kubeTaskPodFunc()
 	return pr.Run(ctx, podFunc)

pkg/kube/pod_runner_test.go

@@ -17,12 +17,17 @@ package kube
 import (
 	"context"
 	"os"
+	"path"
 
+	"github.com/pkg/errors"
 	. "gopkg.in/check.v1"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/client-go/kubernetes/fake"
 	"k8s.io/client-go/testing"
+
+	"github.com/kanisterio/kanister/pkg/consts"
+	"github.com/kanisterio/kanister/pkg/field"
 )
 
 type PodRunnerTestSuite struct{}
@@ -109,9 +114,88 @@ func (s *PodRunnerTestSuite) TestPodRunnerForSuccessCase(c *C) {
 	cancel()
 }
 
+// TestPodRunnerWithJobIDDebugLabelForSuccessCase: This test adds a debug entry (kanister.io/JobID) into the context and verifies the
+// pod got created with corresponding label using the entry or not.
+func (s *PodRunnerTestSuite) TestPodRunnerWithJobIDDebugLabelForSuccessCase(c *C) {
+	randomUUID := "xyz123"
+	for _, tc := range []struct {
+		name        string
+		targetKey   string
+		targetValue string
+		hasError    bool
+	}{
+		{
+			name:        "target key present",
+			targetKey:   path.Join(consts.LabelPrefix, "JobID"),
+			targetValue: randomUUID,
+			hasError:    false,
+		},
+		{
+			name:        "target key not present",
+			targetKey:   path.Join(consts.LabelPrefix, "NonJobID"),
+			targetValue: "some-other-value",
+			hasError:    true,
+		},
+	} {
+		ctx, cancel := context.WithCancel(context.Background())
+		ctx = field.Context(ctx, tc.targetKey, randomUUID)
+		cli := fake.NewSimpleClientset()
+		cli.PrependReactor("create", "pods", func(action testing.Action) (handled bool, ret runtime.Object, err error) {
+			return false, nil, nil
+		})
+		cli.PrependReactor("get", "pods", func(action testing.Action) (handled bool, ret runtime.Object, err error) {
+			p := &corev1.Pod{
+				Status: corev1.PodStatus{
+					Phase: corev1.PodRunning,
+				},
+			}
+			return true, p, nil
+		})
+		po := &PodOptions{
+			Namespace: podRunnerNS,
+			Name:      podName,
+			Command:   []string{"sh", "-c", "tail -f /dev/null"},
+		}
+		deleted := make(chan struct{})
+		cli.PrependReactor("delete", "pods", func(action testing.Action) (handled bool, ret runtime.Object, err error) {
+			c.Log("Pod deleted due to Context Cancelled")
+			close(deleted)
+			return true, nil, nil
+		})
+		var targetKey = path.Join(consts.LabelPrefix, "JobID")
+		AddLabelsToPodOptionsFromContext(ctx, po, targetKey)
+		pr := NewPodRunner(cli, po)
+		errorCh := make(chan error)
+		go func() {
+			_, err := pr.Run(ctx, afterPodRunTestKeyPresentFunc(targetKey, randomUUID, tc.hasError, deleted))
+			errorCh <- err
+		}()
+		deleted <- struct{}{}
+		c.Assert(<-errorCh, IsNil)
+		cancel()
+	}
+}
+
 func makePodRunnerTestFunc(ch chan struct{}) func(ctx context.Context, pc PodController) (map[string]interface{}, error) {
 	return func(ctx context.Context, pc PodController) (map[string]interface{}, error) {
 		<-ch
 		return nil, nil
 	}
 }
+
+func afterPodRunTestKeyPresentFunc(labelKey, labelValue string, ignoreError bool, ch chan struct{}) func(ctx context.Context, pc PodController) (map[string]interface{}, error) {
+	return func(ctx context.Context, pc PodController) (map[string]interface{}, error) {
+		<-ch
+		if ignoreError {
+			return nil, nil
+		}
+		value, ok := pc.Pod().Labels[labelKey]
+		if !ok {
+			return nil, errors.New("Key not present")
+		}
+		if value != labelValue {
+			return nil, errors.New("Value mismatch")
+		}
+		return nil, nil
+	}
+}

pkg/kube/utils.go

@@ -21,6 +21,8 @@ import (
 	osversioned "github.com/openshift/client-go/apps/clientset/versioned"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/client-go/kubernetes"
+
+	"github.com/kanisterio/kanister/pkg/field"
 )
 
 const (
@@ -171,3 +173,30 @@ func PVCContainsReadOnlyAccessMode(pvc *corev1.PersistentVolumeClaim) bool {
 
 	return false
 }
+
+// AddLabelsToPodOptions adds additional label selector to `PodOptions`. It extracts the value from the context
+// if targetkey is present and assigns to the podoptions.
+func AddLabelsToPodOptionsFromContext(
+	ctx context.Context,
+	options *PodOptions,
+	targetKey string,
+) {
+	fields := field.FromContext(ctx)
+	if fields == nil {
+		return
+	}
+	var targetValue = ""
+	for _, f := range fields.Fields() {
+		if f.Key() == targetKey {
+			targetValue = f.Value().(string)
+		}
+	}
+	// Not found
+	if targetValue == "" {
+		return
+	}
+	if options.Labels == nil {
+		options.Labels = make(map[string]string)
+	}
+	options.Labels[targetKey] = targetValue
+}