k8s: clean up bookkeeping fields

internal/k8s/entity.go

@@ -37,17 +37,21 @@ type k8sMeta interface {
 	GetUID() types.UID
 	GetLabels() map[string]string
 	GetOwnerReferences() []metav1.OwnerReference
+	GetAnnotations() map[string]string
 	SetNamespace(ns string)
+	SetManagedFields(managedFields []metav1.ManagedFieldsEntry)
 }
 
 type emptyMeta struct{}
 
-func (emptyMeta) GetName() string                             { return "" }
-func (emptyMeta) GetNamespace() string                        { return "" }
-func (emptyMeta) GetUID() types.UID                           { return "" }
-func (emptyMeta) GetLabels() map[string]string                { return make(map[string]string) }
-func (emptyMeta) GetOwnerReferences() []metav1.OwnerReference { return nil }
-func (emptyMeta) SetNamespace(ns string)                      {}
+func (emptyMeta) GetName() string                                 { return "" }
+func (emptyMeta) GetNamespace() string                            { return "" }
+func (emptyMeta) GetUID() types.UID                               { return "" }
+func (emptyMeta) GetAnnotations() map[string]string               { return make(map[string]string) }
+func (emptyMeta) GetLabels() map[string]string                    { return make(map[string]string) }
+func (emptyMeta) GetOwnerReferences() []metav1.OwnerReference     { return nil }
+func (emptyMeta) SetNamespace(ns string)                          {}
+func (emptyMeta) SetManagedFields(mf []metav1.ManagedFieldsEntry) {}
 
 var _ k8sMeta = emptyMeta{}
 var _ k8sMeta = &metav1.ObjectMeta{}
@@ -105,6 +109,18 @@ func (e K8sEntity) GVK() schema.GroupVersionKind {
 	return gvk
 }
 
+// Clean up internal bookkeeping fields. See
+// https://github.com/kubernetes/kubernetes/issues/90066
+func (e K8sEntity) Clean() {
+	m := e.meta()
+	m.SetManagedFields(nil)
+
+	annotations := m.GetAnnotations()
+	if len(annotations) != 0 {
+		delete(annotations, "kubectl.kubernetes.io/last-applied-configuration")
+	}
+}
+
 func (e K8sEntity) meta() k8sMeta {
 	if unstruct := e.maybeUnstructuredMeta(); unstruct != nil {
 		return unstruct

internal/k8s/entity_test.go

@@ -268,6 +268,67 @@ func TestMutableAndImmutableEntities(t *testing.T) {
 	}
 }
 
+func TestClean(t *testing.T) {
+	yaml := `apiVersion: v1
+kind: Namespace
+metadata:
+  annotations:
+    kubectl.kubernetes.io/last-applied-configuration: |
+      {"apiVersion":"v1","kind":"Namespace","metadata":{"annotations":{},"labels":{"app.kubernetes.io/managed-by":"tilt"},"name":"elastic-system"},"spec":{}}
+  creationTimestamp: "2020-07-07T14:50:17Z"
+  labels:
+    app.kubernetes.io/managed-by: tilt
+  managedFields:
+  - apiVersion: v1
+    fieldsType: FieldsV1
+    fieldsV1:
+      f:metadata:
+        f:annotations:
+          .: {}
+          f:kubectl.kubernetes.io/last-applied-configuration: {}
+        f:labels:
+          .: {}
+          f:app.kubernetes.io/managed-by: {}
+      f:status:
+        f:phase: {}
+    manager: tilt
+    operation: Update
+    time: "2020-07-07T14:50:17Z"
+  name: elastic-system
+  resourceVersion: "617"
+  selfLink: /api/v1/namespaces/elastic-system
+  uid: fa9710ff-7b19-499c-b0f9-faedd1c84969
+spec:
+  finalizers:
+  - kubernetes
+`
+	entities := mustParseYAML(t, yaml)
+	entities[0].Clean()
+
+	result, err := SerializeSpecYAML(entities)
+	require.NoError(t, err)
+
+	expected := `apiVersion: v1
+kind: Namespace
+metadata:
+  creationTimestamp: "2020-07-07T14:50:17Z"
+  labels:
+    app.kubernetes.io/managed-by: tilt
+  name: elastic-system
+  resourceVersion: "617"
+  selfLink: /api/v1/namespaces/elastic-system
+  uid: fa9710ff-7b19-499c-b0f9-faedd1c84969
+spec:
+  finalizers:
+  - kubernetes
+`
+	assert.Equal(t, expected, result)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+}
+
 func entitiesWithKinds(kinds []string) []K8sEntity {
 	entities := make([]K8sEntity, len(kinds))
 	for i, k := range kinds {

internal/store/build_result.go

@@ -155,6 +155,11 @@ func (r K8sBuildResult) Facets() []model.Facet {
 
 // For kubernetes deploy targets.
 func NewK8sDeployResult(id model.TargetID, uids []types.UID, hashes []k8s.PodTemplateSpecHash, appliedEntities []k8s.K8sEntity) BuildResult {
+	// Remove verbose fields from the YAML.
+	for _, e := range appliedEntities {
+		e.Clean()
+	}
+
 	appliedEntitiesText, err := k8s.SerializeSpecYAML(appliedEntities)
 	if err != nil {
 		appliedEntitiesText = fmt.Sprintf("unable to serialize entities to yaml: %s", err.Error())