[ Bugfix ] [TG-204] Bugfix panic when pod statuses empty (#897)

Author: informalict

cmd/main.go

@@ -442,7 +442,9 @@ func getMyPodInfo(kubecli kubernetes.Interface, namespace, name string) (string,
 			return maskAny(err)
 		}
 		sa = pod.Spec.ServiceAccountName
-		image = k8sutil.GetArangoDBImageIDFromPod(pod)
+		if image, err = k8sutil.GetArangoDBImageIDFromPod(pod); err != nil {
+			return errors.Wrap(err, "failed to get image ID from pod")
+		}
 		if image == "" {
 			// Fallback in case we don't know the id.
 			image = pod.Spec.Containers[0].Image

pkg/deployment/images.go

@@ -160,11 +160,11 @@ func (ib *imagesBuilder) fetchArangoDBImageIDAndVersion(ctx context.Context, cac
 			return true, nil
 		}
 
-		if len(pod.Status.ContainerStatuses) == 0 {
-			log.Warn().Msg("Empty list of ContainerStatuses")
+		imageID, err := k8sutil.GetArangoDBImageIDFromPod(pod)
+		if err != nil {
+			log.Warn().Err(err).Msg("failed to get image ID from pod")
 			return true, nil
 		}
-		imageID := k8sutil.GetArangoDBImageIDFromPod(pod)
 		if imageID == "" {
 			// Fall back to specified image
 			imageID = image

pkg/util/k8sutil/images.go

@@ -24,6 +24,8 @@ import (
 	"strings"
 
 	corev1 "k8s.io/api/core/v1"
+
+	"github.com/arangodb/kube-arangodb/pkg/util/errors"
 )
 
 const (
@@ -40,7 +42,15 @@ func ConvertImageID2Image(imageID string) string {
 }
 
 // GetArangoDBImageIDFromPod returns the ArangoDB specific image from a pod
-func GetArangoDBImageIDFromPod(pod *corev1.Pod) string {
+func GetArangoDBImageIDFromPod(pod *corev1.Pod) (string, error) {
+	if pod == nil {
+		return "", errors.New("failed to get container statuses from nil pod")
+	}
+
+	if len(pod.Status.ContainerStatuses) == 0 {
+		return "", errors.New("empty list of ContainerStatuses")
+	}
+
 	rawImageID := pod.Status.ContainerStatuses[0].ImageID
 	if len(pod.Status.ContainerStatuses) > 1 {
 		for _, containerStatus := range pod.Status.ContainerStatuses {
@@ -49,19 +59,6 @@ func GetArangoDBImageIDFromPod(pod *corev1.Pod) string {
 			}
 		}
 	}
-	return ConvertImageID2Image(rawImageID)
-}
-
-// GetArangoDBContainerFromPod returns the ArangoDB container from a pod
-func GetArangoDBContainerFromPod(pod *corev1.Pod) corev1.Container {
-	arangoc := pod.Spec.Containers[0]
-	if len(pod.Status.ContainerStatuses) > 1 {
-		for _, container := range pod.Spec.Containers {
-			if strings.Contains(container.Name, "server") {
-				arangoc = container
-			}
-		}
-	}
 
-	return arangoc
+	return ConvertImageID2Image(rawImageID), nil
 }

pkg/util/k8sutil/images_test.go

@@ -0,0 +1,95 @@
+//
+// DISCLAIMER
+//
+// Copyright 2016-2022 ArangoDB GmbH, Cologne, Germany
+//
+// 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.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package k8sutil
+
+import (
+	"testing"
+
+	"github.com/arangodb/kube-arangodb/pkg/util/errors"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	corev1 "k8s.io/api/core/v1"
+)
+
+func TestGetArangoDBImageIDFromPod(t *testing.T) {
+	type args struct {
+		pod *corev1.Pod
+	}
+	tests := map[string]struct {
+		args    args
+		want    string
+		wantErr error
+	}{
+		"pid is nil": {
+			wantErr: errors.New("failed to get container statuses from nil pod"),
+		},
+		"container statuses list is empty": {
+			args: args{
+				pod: &corev1.Pod{},
+			},
+			wantErr: errors.New("empty list of ContainerStatuses"),
+		},
+		"image ID from the only container": {
+			args: args{
+				pod: &corev1.Pod{
+					Status: corev1.PodStatus{
+						ContainerStatuses: []corev1.ContainerStatus{
+							{
+								ImageID: dockerPullableImageIDPrefix + "test",
+							},
+						},
+					},
+				},
+			},
+			want: "test",
+		},
+		"image ID from two containers": {
+			args: args{
+				pod: &corev1.Pod{
+					Status: corev1.PodStatus{
+						ContainerStatuses: []corev1.ContainerStatus{
+							{
+								ImageID: dockerPullableImageIDPrefix + "test_arango",
+							},
+							{
+								ImageID: dockerPullableImageIDPrefix + "test1_arango",
+							},
+						},
+					},
+				},
+			},
+			want: "test1_arango",
+		},
+	}
+
+	for testName, testCase := range tests {
+		t.Run(testName, func(t *testing.T) {
+			got, err := GetArangoDBImageIDFromPod(testCase.args.pod)
+			if testCase.wantErr != nil {
+				require.EqualError(t, err, testCase.wantErr.Error())
+				return
+			}
+
+			require.NoError(t, err)
+			assert.Equalf(t, testCase.want, got, "image ID is not as expected")
+		})
+	}
+}