Adds PrependGroupingObject() as apply pre-processor

cmd/kubectl/kubectlcobra/commands.go

@@ -6,6 +6,7 @@ package kubectlcobra
 
 import (
 	"flag"
+	"fmt"
 	"os"
 	"strings"
 
@@ -80,6 +81,7 @@ func updateHelp(names []string, c *cobra.Command) {
 func NewCmdApply(baseName string, f util.Factory, ioStreams genericclioptions.IOStreams) *cobra.Command {
 	o := apply.NewApplyOptions(ioStreams)
 	so := newStatusOptions(f, ioStreams)
+	o.PreProcessorFn = PrependGroupingObject(o)
 
 	cmd := &cobra.Command{
 		Use:                   "apply (-f FILENAME | -k DIRECTORY)",
@@ -118,3 +120,27 @@ func NewCmdApply(baseName string, f util.Factory, ioStreams genericclioptions.IO
 
 	return cmd
 }
+
+// PrependGroupingObject orders the objects to apply so the "grouping"
+// object stores the inventory, and it is first to be applied.
+func PrependGroupingObject(o *apply.ApplyOptions) func() error {
+	return func() error {
+		if o == nil {
+			return fmt.Errorf("ApplyOptions are nil")
+		}
+		infos, err := o.GetObjects()
+		if err != nil {
+			return err
+		}
+		_, exists := findGroupingObject(infos)
+		if exists {
+			if err := addInventoryToGroupingObj(infos); err != nil {
+				return err
+			}
+			if !sortGroupingObject(infos) {
+				return err
+			}
+		}
+		return nil
+	}
+}