Short circuit anno/label transformer for performance.

api/internal/accumulator/resaccumulator.go

@@ -59,6 +59,15 @@ func (ra *ResAccumulator) GetTransformerConfig() *builtinconfig.TransformerConfi
 	return ra.tConfig
 }
 
+// MergeVars accumulates vars into ResAccumulator.
+// A Var is a tuple of name, object reference and field reference.
+// This func takes a list of vars from the current kustomization file and
+// annotates the accumulated resources with the names of the vars that match
+// those resources.  E.g. if there's a var named "sam" that wants to get
+// its data from a ConfigMap named "james", and the resource list contains a
+// ConfigMap named "james", then that ConfigMap will be annotated with the
+// var name "sam".  Later this annotation is used to find the data for "sam"
+// by digging into a particular fieldpath of "james".
 func (ra *ResAccumulator) MergeVars(incoming []types.Var) error {
 	for _, v := range incoming {
 		targetId := resid.NewResIdWithNamespace(v.ObjRef.GVK(), v.ObjRef.Name, v.ObjRef.Namespace)
@@ -104,12 +113,10 @@ func (ra *ResAccumulator) findVarValueFromResources(v types.Var) (interface{}, e
 						"field specified in var '%v' "+
 							"not found in corresponding resource", v)
 				}
-
 				return s, nil
 			}
 		}
 	}
-
 	return "", fmt.Errorf(
 		"var '%v' cannot be mapped to a field "+
 			"in the set of known resources", v)
@@ -125,10 +132,8 @@ func (ra *ResAccumulator) makeVarReplacementMap() (map[string]interface{}, error
 		if err != nil {
 			return nil, err
 		}
-
 		result[v.Name] = s
 	}
-
 	return result, nil
 }