Apply image updates to CronJob objects

This updates the image replacement to switch on the kind of the node,
and change the way the replacements are done for CronJobs.

CronJobs have PodTemplateSpecs embedded deeper in the structure.

Author: bigkevmcd

pkg/update/testdata/leave/expected/cronjob.yaml

@@ -0,0 +1,14 @@
+apiVersion: batch/v1beta1
+kind: CronJob
+metadata:
+  name: foo
+  namespace: bar
+spec:
+  schedule: "*/1 * * * *"
+  jobTemplate:
+    spec:
+      template:
+        spec:
+          containers:
+          - name: c
+            image: helloworld:v1.0.0

pkg/update/testdata/leave/original/cronjob.yaml

@@ -0,0 +1,14 @@
+apiVersion: batch/v1beta1
+kind: CronJob
+metadata:
+  name: foo
+  namespace: bar
+spec:
+  schedule: "*/1 * * * *"
+  jobTemplate:
+    spec:
+      template:
+        spec:
+          containers:
+          - name: c
+            image: helloworld:v1.0.0

pkg/update/testdata/replace/expected/cronjob.yaml

@@ -0,0 +1,14 @@
+apiVersion: batch/v1beta1
+kind: CronJob
+metadata:
+  name: foo
+  namespace: bar
+spec:
+  schedule: "*/1 * * * *"
+  jobTemplate:
+    spec:
+      template:
+        spec:
+          containers:
+          - name: c
+            image: used:v1.1.0

pkg/update/testdata/replace/original/cronjob.yaml

@@ -0,0 +1,14 @@
+apiVersion: batch/v1beta1
+kind: CronJob
+metadata:
+  name: foo
+  namespace: bar
+spec:
+  schedule: "*/1 * * * *"
+  jobTemplate:
+    spec:
+      template:
+        spec:
+          containers:
+          - name: c
+            image: used:v1.0.0

pkg/update/update.go

@@ -56,21 +56,35 @@ func makeUpdateImagesFilter(originalRepo, replacement string) kio.Filter {
 	})
 
 	return kio.FilterFunc(func(objs []*yaml.RNode) ([]*yaml.RNode, error) {
+		tees := []yaml.Filter{
+			yaml.Tee(
+				yaml.Lookup("initContainers"),
+				replaceImageInEachContainer,
+			),
+			yaml.Tee(
+				yaml.Lookup("containers"),
+				replaceImageInEachContainer,
+			),
+		}
+
 		for _, obj := range objs {
-			if err := obj.PipeE(
-				yaml.Lookup("spec", "template", "spec"),
-				yaml.Tee(
-					yaml.Lookup("initContainers"),
-					replaceImageInEachContainer,
-				),
-				yaml.Tee(
-					yaml.Lookup("containers"),
-					replaceImageInEachContainer,
-				),
-			); err != nil {
+			lookup := yaml.Lookup("spec", "template", "spec")
+			switch kind(obj) {
+			case "CronJob":
+				lookup = yaml.Lookup("spec", "jobTemplate", "spec", "template", "spec")
+			}
+			if err := obj.PipeE(append([]yaml.Filter{lookup}, tees...)...); err != nil {
 				return nil, err
 			}
 		}
 		return objs, nil
 	})
 }
+
+func kind(a *yaml.RNode) string {
+	f := a.Field(yaml.KindField)
+	if f != nil {
+		return yaml.GetValue(f.Value)
+	}
+	return ""
+}