Check labels in e2e PipelineRun tests and document label propagation

docs/pipelineruns.md

@@ -97,6 +97,26 @@ of the `TaskRun` resource object.
 For examples and more information about specifying service accounts, see the
 [`ServiceAccount`](./auth.md) reference topic.
 
+## Labels
+
+Any labels specified in the metadata field of a `PipelineRun` will be
+propagated to the `TaskRuns` created automatically for each `Task` in the
+`Pipeline` and then to the `Pods` created for those `TaskRuns`. In addition,
+the following labels will be added automatically:
+
+* `pipeline.knative.dev/pipeline` will contain the name of the `Pipeline`
+* `pipeline.knative.dev/pipelineRun` will contain the name of the `PipelineRun`
+
+These labels make it easier to find the resources that are associated with a
+given pipeline.
+
+For example, to find all `Pods` created by a `Pipeline` named test-pipeline,
+you could use the following command:
+
+```shell
+kubectl get pods --all-namespaces -l pipeline.knative.dev/pipeline=test-pipeline
+```
+
 ## Cancelling a PipelineRun
 
 In order to cancel a running pipeline (`PipelineRun`), you need to update its

docs/taskruns.md

@@ -152,6 +152,30 @@ of the `TaskRun` resource object.
 For examples and more information about specifying service accounts, see the
 [`ServiceAccount`](./auth.md) reference topic.
 
+## Labels
+
+Any labels specified in the metadata field of a `TaskRun` will be
+propagated to the `Pod` created to execute the `Task`. In addition,
+the following label will be added automatically:
+
+* `pipeline.knative.dev/taskRun` will contain the name of the `TaskRun`
+
+If the `TaskRun` was created automatically by a `PipelineRun`, then the
+following two labels will also be added to the `TaskRun` and `Pod`:
+
+* `pipeline.knative.dev/pipeline` will contain the name of the `Pipeline`
+* `pipeline.knative.dev/pipelineRun` will contain the name of the `PipelineRun`
+
+These labels make it easier to find the resources that are associated with a
+given `TaskRun`.
+
+For example, to find all `Pods` created by a `TaskRun` named test-taskrun,
+you could use the following command:
+
+```shell
+kubectl get pods --all-namespaces -l pipeline.knative.dev/taskRun=test-taskrun
+```
+
 ## Cancelling a TaskRun
 
 In order to cancel a running task (`TaskRun`), you need to update its spec to

test/pipelinerun_test.go

@@ -138,7 +138,8 @@ func TestPipelineRun(t *testing.T) {
 			td.testSetup(t, c, namespace, i)
 
 			prName := fmt.Sprintf("%s%d", pipelineRunName, i)
-			if _, err := c.PipelineRunClient.Create(td.pipelineRunFunc(i, namespace)); err != nil {
+			pr, err := c.PipelineRunClient.Create(td.pipelineRunFunc(i, namespace))
+			if err != nil {
 				t.Fatalf("Failed to create PipelineRun `%s`: %s", prName, err)
 			}
 
@@ -160,16 +161,22 @@ func TestPipelineRun(t *testing.T) {
 				if !r.Status.GetCondition(duckv1alpha1.ConditionSucceeded).IsTrue() {
 					t.Fatalf("Expected TaskRun %s to have succeeded but Status is %v", taskRunName, r.Status)
 				}
-				for name, key := range map[string]string{
-					pipelineRunName: pipeline.PipelineRunLabelKey,
-					pipelineName:    pipeline.PipelineLabelKey,
-				} {
-					expectedName := getName(name, i)
-					lbl := pipeline.GroupName + key
-					if val := r.Labels[lbl]; val != expectedName {
-						t.Errorf("Expected label %s=%s but got %s", lbl, expectedName, val)
-					}
+
+				// Check label propagation to Tasks. Presize map with len(pr.ObjectMeta.Labels)
+				// for custom labels, +2 for the labels added in the PipelineRun controller,
+				// and +1 for the label added in the TaskRun controller.
+				labels := make(map[string]string, len(pr.ObjectMeta.Labels)+3)
+				for key, val := range pr.ObjectMeta.Labels {
+					labels[key] = val
 				}
+				// These labels are added to every TaskRun by the PipelineRun controller
+				labels[pipeline.GroupName+pipeline.PipelineLabelKey] = getName(pipelineName, i)
+				labels[pipeline.GroupName+pipeline.PipelineRunLabelKey] = getName(pipelineRunName, i)
+				assertLabelsMatch(t, labels, r.ObjectMeta.Labels)
+
+				// Check label propagation to Pods. This label is added to every Pod by the TaskRun controller
+				labels[pipeline.GroupName + pipeline.TaskRunLabelKey] = taskRunName
+				assertLabelsMatch(t, labels, getPodForTaskRun(t, c.KubeClient, namespace, r).ObjectMeta.Labels)
 			}
 
 			matchKinds := map[string][]string{"PipelineRun": {prName}, "TaskRun": expectedTaskRunNames}
@@ -322,10 +329,12 @@ func getPipelineRunSecret(suffix int, namespace string) *corev1.Secret {
 }
 
 func getHelloWorldPipelineRun(suffix int, namespace string) *v1alpha1.PipelineRun {
-	return tb.PipelineRun(getName(pipelineRunName, suffix), namespace, tb.PipelineRunSpec(
-		getName(pipelineName, suffix),
-		tb.PipelineRunServiceAccount(fmt.Sprintf("%s%d", saName, suffix)),
-	))
+	return tb.PipelineRun(getName(pipelineRunName, suffix), namespace,
+		tb.PipelineRunLabel("hello-world-key", "hello-world-value"),
+		tb.PipelineRunSpec(getName(pipelineName, suffix),
+			tb.PipelineRunServiceAccount(fmt.Sprintf("%s%d", saName, suffix)),
+		),
+	)
 }
 
 func getName(namespace string, suffix int) string {
@@ -370,3 +379,25 @@ func collectMatchingEvents(kubeClient *knativetest.KubeClient, namespace string,
 		}
 	}
 }
+
+func getPodForTaskRun(t *testing.T, kubeClient *knativetest.KubeClient, namespace string, tr *v1alpha1.TaskRun) *corev1.Pod {
+	// The Pod name has a random suffix, so we filter by label to find the one we care about.
+	pods, err := kubeClient.Kube.CoreV1().Pods(namespace).List(metav1.ListOptions{
+		LabelSelector: pipeline.GroupName + pipeline.TaskRunLabelKey + " = " + tr.Name,
+	})
+	if err != nil {
+		t.Fatalf("Couldn't get expected Pod for %s: %s", tr.Name, err)
+	}
+	if numPods := len(pods.Items); numPods != 1 {
+		t.Fatalf("Expected 1 Pod for %s, but got %d Pods", tr.Name, numPods)
+	}
+	return &pods.Items[0]
+}
+
+func assertLabelsMatch(t *testing.T, expectedLabels, actualLabels map[string]string) {
+	for key, expectedVal := range expectedLabels {
+		if actualVal := actualLabels[key]; actualVal != expectedVal {
+			t.Errorf("Expected labels containing %s=%s but labels were %v", key, expectedVal, actualLabels)
+		}
+	}
+}