Add a small integration test library to dump pod logs on test failures.

Signed-off-by: Matt Moyer <moyerm@vmware.com>

test/library/dumplogs.go

@@ -0,0 +1,49 @@
+// Copyright 2020 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package library
+
+import (
+	"bufio"
+	"context"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// DumpLogs is meant to be called in a `defer` to dump the logs of components in the cluster on a test failure.
+func DumpLogs(t *testing.T, namespace string) {
+	// Only trigger on failed tests.
+	if !t.Failed() {
+		return
+	}
+
+	kubeClient := NewClientset(t)
+	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
+	defer cancel()
+
+	logTailLines := int64(40)
+	pods, err := kubeClient.CoreV1().Pods(namespace).List(ctx, metav1.ListOptions{})
+	require.NoError(t, err)
+
+	for _, pod := range pods.Items {
+		for _, container := range pod.Status.ContainerStatuses {
+			t.Logf("pod %s/%s container %s restarted %d times:", pod.Namespace, pod.Name, container.Name, container.RestartCount)
+			req := kubeClient.CoreV1().Pods(namespace).GetLogs(pod.Name, &corev1.PodLogOptions{
+				Container: container.Name,
+				TailLines: &logTailLines,
+			})
+			logReader, err := req.Stream(ctx)
+			require.NoError(t, err)
+
+			scanner := bufio.NewScanner(logReader)
+			for scanner.Scan() {
+				t.Logf("%s/%s/%s > %s", pod.Namespace, pod.Name, container.Name, scanner.Text())
+			}
+			require.NoError(t, scanner.Err())
+		}
+	}
+}