add variable and method comments

internal/service/process_relationships.go

@@ -9,13 +9,9 @@ import (
 	"go.equinixmetal.net/infra9-metal-bridge/internal/permissions"
 )
 
-type relationshipStats struct {
-	parentCreated               bool
-	parentsDeleted              int
-	subjectRelationshipsCreated int
-	subjectRelationshipsDeleted int
-}
-
+// processRelationships determines the changes between what is wanted and what is live and executes on the differences.
+// Relationship creations use events.
+// Relationship deletions use the api, as delete events delete all related resources and not just the provided ones.
 func (s *service) processRelationships(ctx context.Context, eventType string, relationships Relationships) int {
 	rlogger := s.logger.With("resource.id", relationships.Resource.PrefixedID())
 
@@ -161,6 +157,7 @@ func (s *service) processRelationships(ctx context.Context, eventType string, re
 	return changes
 }
 
+// mapRelationWants returns the parent relation if provided and a map of Subjects -> relation.
 func (s *service) mapRelationWants(relationships Relationships) (*Relation, map[gidx.PrefixedID]RelationshipType) {
 	var wantParent *Relation
 
@@ -177,6 +174,9 @@ func (s *service) mapRelationWants(relationships Relationships) (*Relation, map[
 	return wantParent, wantSubject
 }
 
+// getRelationshipMap fetches the provided resources relationships, as the source resource and the destination subject.
+// Returned are two maps, the first maps Subject IDs -> Relationship
+// The second map, maps Resource IDs -> relationship
 func (s *service) getRelationshipMap(ctx context.Context, resource IDPrefixableResource, relatedObjectType ObjectType) (map[gidx.PrefixedID]RelationshipType, map[gidx.PrefixedID]RelationshipType, error) {
 	liveResource, err := s.perms.ListResourceRelationships(ctx, resource.PrefixedID(), "")
 	if err != nil {