Clean up and comment some desiredset funcs

pkg/apply/desiredset_apply.go

@@ -80,6 +80,7 @@ func (o *desiredSet) apply() error {
 		return err
 	}
 
+	// Create maps for labels and annotations containing the identifying hash used for rate limiting.
 	labelSet, annotationSet, err := GetLabelsAndAnnotations(o.setID, o.owner)
 	if err != nil {
 		return o.err(err)
@@ -141,6 +142,7 @@ func (o *desiredSet) debugID() string {
 	})
 }
 
+// collect converts a list of runtime objects into an ObjectByGVK map.
 func (o *desiredSet) collect(objList []runtime.Object) objectset.ObjectByGVK {
 	result := objectset.ObjectByGVK{}
 	for _, obj := range objList {
@@ -189,6 +191,8 @@ func GetSelectorFromOwner(setID string, owner runtime.Object) (labels.Selector,
 	return GetSelector(ownerLabel)
 }
 
+// GetSelector returns the label selector for the owner object, which is useful
+// to list the dependents.
 func GetSelector(labelSet map[string]string) (labels.Selector, error) {
 	req, err := labels.NewRequirement(LabelHash, selection.Equals, []string{labelSet[LabelHash]})
 	if err != nil {
@@ -197,6 +201,10 @@ func GetSelector(labelSet map[string]string) (labels.Selector, error) {
 	return labels.NewSelector().Add(*req), nil
 }
 
+// GetLabelsAndAnnotations returns a new map of annotations with the setID
+// and/or owner in it. It also returns a new map of labels, which contains a
+// hash over the annotations. The hash is used to identify resources that
+// belong to the same setID/owner.
 func GetLabelsAndAnnotations(setID string, owner runtime.Object) (map[string]string, map[string]string, error) {
 	if setID == "" && owner == nil {
 		return nil, nil, fmt.Errorf("set ID or owner must be set")
@@ -227,6 +235,8 @@ func GetLabelsAndAnnotations(setID string, owner runtime.Object) (map[string]str
 	return labels, annotations, nil
 }
 
+// injectLabelsAndAnnotations returns the desiredSet's objects. The given
+// labels and annotations extend and overwrite existing labels.
 func (o *desiredSet) injectLabelsAndAnnotations(labels, annotations map[string]string) ([]runtime.Object, error) {
 	var result []runtime.Object
 
@@ -248,6 +258,7 @@ func (o *desiredSet) injectLabelsAndAnnotations(labels, annotations map[string]s
 	return result, nil
 }
 
+// setAnnotations overwrites the annotations in meta with the given annotations map.
 func setAnnotations(meta metav1.Object, annotations map[string]string) {
 	objAnn := meta.GetAnnotations()
 	if objAnn == nil {
@@ -260,6 +271,7 @@ func setAnnotations(meta metav1.Object, annotations map[string]string) {
 	meta.SetAnnotations(objAnn)
 }
 
+// setLabels overwrites the labels in meta with the given labels map.
 func setLabels(meta metav1.Object, labels map[string]string) {
 	objLabels := meta.GetLabels()
 	if objLabels == nil {

pkg/apply/desiredset_compare.go

@@ -23,7 +23,6 @@ import (
 	"k8s.io/apimachinery/pkg/util/json"
 	"k8s.io/apimachinery/pkg/util/jsonmergepatch"
 	"k8s.io/apimachinery/pkg/util/strategicpatch"
-	"k8s.io/client-go/dynamic"
 )
 
 const (
@@ -45,6 +44,10 @@ var (
 	}
 )
 
+// prepareObjectForCreate returns a copy of the object with the "applied"
+// annotation set. The "applied" annotation contains a serialized and pruned
+// representation of obj, e.g. Strings are shortened to 64 characters and bytes
+// are skipped.
 func prepareObjectForCreate(gvk schema.GroupVersionKind, obj runtime.Object) (runtime.Object, error) {
 	serialized, err := serializeApplied(obj)
 	if err != nil {
@@ -76,6 +79,8 @@ func prepareObjectForCreate(gvk schema.GroupVersionKind, obj runtime.Object) (ru
 	return obj, nil
 }
 
+// originalAndModified returns the original bytes from the oldObject's
+// "applied" annotation and the modified bytes for the newObject.
 func originalAndModified(gvk schema.GroupVersionKind, oldMetadata v1.Object, newObject runtime.Object) ([]byte, []byte, error) {
 	original, err := getOriginalBytes(gvk, oldMetadata)
 	if err != nil {
@@ -169,6 +174,7 @@ func sanitizePatch(patch []byte, removeObjectSetAnnotation bool) ([]byte, error)
 	return json.Marshal(data)
 }
 
+// applyPatch applies the patch to the object and returns true if the object was changed.
 func applyPatch(gvk schema.GroupVersionKind, reconciler Reconciler, patcher Patcher, debugID string, ignoreOriginal bool, oldObject, newObject runtime.Object, diffPatches [][]byte) (bool, error) {
 	oldMetadata, err := meta.Accessor(oldObject)
 	if err != nil {
@@ -235,7 +241,8 @@ func applyPatch(gvk schema.GroupVersionKind, reconciler Reconciler, patcher Patc
 	return true, err
 }
 
-func (o *desiredSet) compareObjects(gvk schema.GroupVersionKind, reconciler Reconciler, patcher Patcher, client dynamic.NamespaceableResourceInterface, debugID string, oldObject, newObject runtime.Object, force bool) error {
+// compareObjects updates the resource with the passed in patcher. It considers WithDiffPatch and WithReconciler.
+func (o *desiredSet) compareObjects(gvk schema.GroupVersionKind, reconciler Reconciler, patcher Patcher, debugID string, oldObject, newObject runtime.Object) error {
 	oldMetadata, err := meta.Accessor(oldObject)
 	if err != nil {
 		return err

pkg/apply/desiredset_process.go

@@ -207,6 +207,9 @@ func (o *desiredSet) filterCrossVersion(gvk schema.GroupVersionKind, keys []obje
 	return result
 }
 
+// process executes the apply by creating, updating, and deleting objects. It
+// compares the desired state to the current state and builds necessary
+// patchers.
 func (o *desiredSet) process(debugID string, set labels.Selector, gvk schema.GroupVersionKind, objs objectset.ObjectByKey) {
 	controller, client, err := o.getControllerAndClient(debugID, gvk)
 	if err != nil {
@@ -316,7 +319,7 @@ func (o *desiredSet) process(debugID string, set labels.Selector, gvk schema.Gro
 	}
 
 	updateF := func(k objectset.ObjectKey) {
-		err := o.compareObjects(gvk, reconciler, patcher, client, debugID, existing[k], objs[k], len(toCreate) > 0 || len(toDelete) > 0)
+		err := o.compareObjects(gvk, reconciler, patcher, debugID, existing[k], objs[k])
 		if err == ErrReplace {
 			deleteF(k, true)
 			o.err(fmt.Errorf("DesiredSet - Replace Wait %s %s for %s", gvk, k, debugID))