fix sort-by output problem

pkg/kubectl/cmd/util/factory_builder.go

@@ -32,7 +32,6 @@ import (
 	"k8s.io/kubernetes/pkg/kubectl/plugins"
 	"k8s.io/kubernetes/pkg/kubectl/resource"
 	"k8s.io/kubernetes/pkg/printers"
-	printersinternal "k8s.io/kubernetes/pkg/printers/internalversion"
 )
 
 type ring2Factory struct {
@@ -103,16 +102,6 @@ func (f *ring2Factory) PrinterForMapping(cmd *cobra.Command, isLocal bool, outpu
 
 		printer = printers.NewVersionedPrinter(printer, mapping.ObjectConvertor, version, mapping.GroupVersionKind.GroupVersion())
 
-	} else {
-		// We add handlers to the printer in case it is printers.HumanReadablePrinter.
-		// printers.AddHandlers expects concrete type of printers.HumanReadablePrinter
-		// as its parameter because of this we have to do a type check on printer and
-		// extract out concrete HumanReadablePrinter from it. We are then able to attach
-		// handlers on it.
-		if humanReadablePrinter, ok := printer.(*printers.HumanReadablePrinter); ok {
-			printersinternal.AddHandlers(humanReadablePrinter)
-			printer = humanReadablePrinter
-		}
 	}
 
 	return printer, nil

pkg/kubectl/cmd/util/printing.go

@@ -26,6 +26,7 @@ import (
 	"k8s.io/kubernetes/pkg/kubectl"
 	"k8s.io/kubernetes/pkg/kubectl/resource"
 	"k8s.io/kubernetes/pkg/printers"
+	printersinternal "k8s.io/kubernetes/pkg/printers/internalversion"
 
 	"github.com/spf13/cobra"
 )
@@ -126,6 +127,13 @@ func PrinterForCommand(cmd *cobra.Command, outputOpts *printers.OutputOptions, m
 		return nil, err
 	}
 
+	// we try to convert to HumanReadablePrinter, if return ok, it must be no generic
+	// we execute AddHandlers() here before maybeWrapSortingPrinter so that we don't
+	// need to convert to delegatePrinter again then invoke AddHandlers()
+	if humanReadablePrinter, ok := printer.(*printers.HumanReadablePrinter); ok {
+		printersinternal.AddHandlers(humanReadablePrinter)
+	}
+
 	return maybeWrapSortingPrinter(cmd, printer), nil
 }