add a discarding printer for testing and delegation

pkg/kubectl/cmd/delete.go

@@ -34,6 +34,7 @@ import (
 	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
 	kubectlwait "k8s.io/kubernetes/pkg/kubectl/cmd/wait"
 	"k8s.io/kubernetes/pkg/kubectl/genericclioptions"
+	"k8s.io/kubernetes/pkg/kubectl/genericclioptions/printers"
 	"k8s.io/kubernetes/pkg/kubectl/genericclioptions/resource"
 	"k8s.io/kubernetes/pkg/kubectl/util/i18n"
 )
@@ -335,7 +336,7 @@ func (o *DeleteOptions) DeleteResult(r *resource.Result) error {
 		DynamicClient:  o.DynamicClient,
 		Timeout:        effectiveTimeout,
 
-		Printer:     kubectlwait.NewDiscardingPrinter(),
+		Printer:     printers.NewDiscardingPrinter(),
 		ConditionFn: kubectlwait.IsDeleted,
 		IOStreams:   o.IOStreams,
 	}

pkg/kubectl/cmd/wait/BUILD

@@ -46,6 +46,7 @@ go_test(
     embed = [":go_default_library"],
     deps = [
         "//pkg/kubectl/genericclioptions:go_default_library",
+        "//pkg/kubectl/genericclioptions/printers:go_default_library",
         "//pkg/kubectl/genericclioptions/resource:go_default_library",
         "//vendor/github.com/davecgh/go-spew/spew:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/meta:go_default_library",

pkg/kubectl/cmd/wait/wait.go

@@ -18,7 +18,6 @@ package wait
 
 import (
 	"fmt"
-	"io"
 	"strings"
 	"time"
 
@@ -320,11 +319,3 @@ func (w ConditionalWait) isConditionMet(event watch.Event) (bool, error) {
 	obj := event.Object.(*unstructured.Unstructured)
 	return w.checkCondition(obj)
 }
-
-// NewDiscardingPrinter is a printer that discards all objects
-// TODO use the real discarding printer from a different pull I just opened.
-func NewDiscardingPrinter() printers.ResourcePrinterFunc {
-	return printers.ResourcePrinterFunc(func(runtime.Object, io.Writer) error {
-		return nil
-	})
-}

pkg/kubectl/cmd/wait/wait_test.go

@@ -34,6 +34,7 @@ import (
 	dynamicfakeclient "k8s.io/client-go/dynamic/fake"
 	clienttesting "k8s.io/client-go/testing"
 	"k8s.io/kubernetes/pkg/kubectl/genericclioptions"
+	"k8s.io/kubernetes/pkg/kubectl/genericclioptions/printers"
 	"k8s.io/kubernetes/pkg/kubectl/genericclioptions/resource"
 )
 
@@ -222,7 +223,7 @@ func TestWaitForDeletion(t *testing.T) {
 				DynamicClient:  fakeClient,
 				Timeout:        test.timeout,
 
-				Printer:     NewDiscardingPrinter(),
+				Printer:     printers.NewDiscardingPrinter(),
 				ConditionFn: IsDeleted,
 				IOStreams:   genericclioptions.NewTestIOStreamsDiscard(),
 			}
@@ -454,7 +455,7 @@ func TestWaitForCondition(t *testing.T) {
 				DynamicClient:  fakeClient,
 				Timeout:        test.timeout,
 
-				Printer:     NewDiscardingPrinter(),
+				Printer:     printers.NewDiscardingPrinter(),
 				ConditionFn: ConditionalWait{conditionName: "the-condition", conditionStatus: "status-value"}.IsConditionMet,
 				IOStreams:   genericclioptions.NewTestIOStreamsDiscard(),
 			}

pkg/kubectl/genericclioptions/printers/BUILD

@@ -3,6 +3,7 @@ load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 go_library(
     name = "go_default_library",
     srcs = [
+        "discard.go",
         "interface.go",
         "json.go",
         "name.go",

pkg/kubectl/genericclioptions/printers/discard.go

@@ -0,0 +1,30 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package printers
+
+import (
+	"io"
+
+	"k8s.io/apimachinery/pkg/runtime"
+)
+
+// NewDiscardingPrinter is a printer that discards all objects
+func NewDiscardingPrinter() ResourcePrinterFunc {
+	return ResourcePrinterFunc(func(runtime.Object, io.Writer) error {
+		return nil
+	})
+}

pkg/kubectl/genericclioptions/printers/interface.go

@@ -25,6 +25,11 @@ import (
 // ResourcePrinterFunc is a function that can print objects
 type ResourcePrinterFunc func(runtime.Object, io.Writer) error
 
+// PrintObj implements ResourcePrinter
+func (fn ResourcePrinterFunc) PrintObj(obj runtime.Object, w io.Writer) error {
+	return fn(obj, w)
+}
+
 // ResourcePrinter is an interface that knows how to print runtime objects.
 type ResourcePrinter interface {
 	// Print receives a runtime object, formats it and prints it to a writer.