remove todo(#42787)Add fallback for cronjobs, and move some useful function to cmdutil

pkg/kubectl/cmd/BUILD

@@ -106,10 +106,8 @@ go_library(
         "//vendor/github.com/renstrom/dedent:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",
         "//vendor/github.com/spf13/pflag:go_default_library",
-        "//vendor/k8s.io/api/apps/v1beta1:go_default_library",
         "//vendor/k8s.io/api/batch/v1:go_default_library",
         "//vendor/k8s.io/api/batch/v1beta1:go_default_library",
-        "//vendor/k8s.io/api/batch/v2alpha1:go_default_library",
         "//vendor/k8s.io/api/core/v1:go_default_library",
         "//vendor/k8s.io/api/extensions/v1beta1:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
@@ -134,7 +132,6 @@ go_library(
         "//vendor/k8s.io/apimachinery/pkg/version:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/watch:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/util/flag:go_default_library",
-        "//vendor/k8s.io/client-go/discovery:go_default_library",
         "//vendor/k8s.io/client-go/rest:go_default_library",
         "//vendor/k8s.io/client-go/tools/clientcmd:go_default_library",
         "//vendor/k8s.io/client-go/tools/portforward:go_default_library",

pkg/kubectl/cmd/create_deployment.go

@@ -22,8 +22,6 @@ import (
 
 	"github.com/spf13/cobra"
 
-	appsv1beta1 "k8s.io/api/apps/v1beta1"
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/kubernetes/pkg/kubectl"
 	"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
 	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
@@ -63,35 +61,6 @@ func NewCmdCreateDeployment(f cmdutil.Factory, cmdOut, cmdErr io.Writer) *cobra.
 	return cmd
 }
 
-// fallbackGeneratorNameIfNecessary returns the name of the old generator
-// (v1beta1) if server does not support apps/v1beta1 deployments. Otherwise, the
-// generator string is returned unchanged.
-//
-// If the generator name is changed, print a warning message to let the user
-// know.
-func fallbackGeneratorNameIfNecessary(
-	generatorName string,
-	resourcesList []*metav1.APIResourceList,
-	cmdErr io.Writer,
-) string {
-
-	if generatorName == cmdutil.DeploymentBasicAppsV1Beta1GeneratorName &&
-		!contains(resourcesList, appsv1beta1.SchemeGroupVersion.WithResource("deployments")) {
-
-		fmt.Fprintf(cmdErr,
-			"WARNING: New deployments generator %q specified, "+
-				"but apps/v1beta1.Deployments are not available. "+
-				"Falling back to %q.\n",
-			cmdutil.DeploymentBasicAppsV1Beta1GeneratorName,
-			cmdutil.DeploymentBasicV1Beta1GeneratorName,
-		)
-
-		return cmdutil.DeploymentBasicV1Beta1GeneratorName
-	}
-
-	return generatorName
-}
-
 // generatorFromName returns the appropriate StructuredGenerator based on the
 // generatorName. If the generatorName is unrecognized, then return (nil,
 // false).
@@ -150,7 +119,7 @@ func createDeployment(f cmdutil.Factory, cmdOut, cmdErr io.Writer,
 
 	// It is possible we have to modify the user-provided generator name if
 	// the server does not have support for the requested generator.
-	generatorName = fallbackGeneratorNameIfNecessary(generatorName, resourcesList, cmdErr)
+	generatorName = cmdutil.FallbackGeneratorNameIfNecessary(generatorName, resourcesList, cmdErr)
 
 	imageNames := cmdutil.GetFlagStringSlice(cmd, "image")
 	generator, ok := generatorFromName(generatorName, imageNames, deploymentName)

pkg/kubectl/cmd/run.go

@@ -25,15 +25,12 @@ import (
 
 	batchv1 "k8s.io/api/batch/v1"
 	batchv1beta1 "k8s.io/api/batch/v1beta1"
-	batchv2alpha1 "k8s.io/api/batch/v2alpha1"
 	extensionsv1beta1 "k8s.io/api/extensions/v1beta1"
 	"k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/watch"
-	"k8s.io/client-go/discovery"
 	"k8s.io/kubernetes/pkg/api"
 	coreclient "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset/typed/core/internalversion"
 	conditions "k8s.io/kubernetes/pkg/client/unversioned"
@@ -226,7 +223,7 @@ func RunRun(f cmdutil.Factory, cmdIn io.Reader, cmdOut, cmdErr io.Writer, cmd *c
 	generatorName := cmdutil.GetFlagString(cmd, "generator")
 	schedule := cmdutil.GetFlagString(cmd, "schedule")
 	if len(schedule) != 0 && len(generatorName) == 0 {
-		if contains(resourcesList, batchv1beta1.SchemeGroupVersion.WithResource("cronjobs")) {
+		if cmdutil.Contains(resourcesList, batchv1beta1.SchemeGroupVersion.WithResource("cronjobs")) {
 			generatorName = cmdutil.CronJobV1Beta1GeneratorName
 		} else {
 			generatorName = cmdutil.CronJobV2Alpha1GeneratorName
@@ -237,13 +234,13 @@ func RunRun(f cmdutil.Factory, cmdIn io.Reader, cmdOut, cmdErr io.Writer, cmd *c
 		case api.RestartPolicyAlways:
 			// TODO: we need to deprecate this along with extensions/v1beta1.Deployments
 			// in favor of the new generator for apps/v1beta1.Deployments
-			if contains(resourcesList, extensionsv1beta1.SchemeGroupVersion.WithResource("deployments")) {
+			if cmdutil.Contains(resourcesList, extensionsv1beta1.SchemeGroupVersion.WithResource("deployments")) {
 				generatorName = cmdutil.DeploymentV1Beta1GeneratorName
 			} else {
 				generatorName = cmdutil.RunV1GeneratorName
 			}
 		case api.RestartPolicyOnFailure:
-			if contains(resourcesList, batchv1.SchemeGroupVersion.WithResource("jobs")) {
+			if cmdutil.Contains(resourcesList, batchv1.SchemeGroupVersion.WithResource("jobs")) {
 				generatorName = cmdutil.JobV1GeneratorName
 			} else {
 				generatorName = cmdutil.RunPodV1GeneratorName
@@ -253,13 +250,7 @@ func RunRun(f cmdutil.Factory, cmdIn io.Reader, cmdOut, cmdErr io.Writer, cmd *c
 		}
 	}
 
-	// TODO: this should be removed alongside with extensions/v1beta1 depployments generator
-	generatorName = fallbackGeneratorNameIfNecessary(generatorName, resourcesList, cmdErr)
-
-	if generatorName == cmdutil.CronJobV2Alpha1GeneratorName &&
-		!contains(resourcesList, batchv2alpha1.SchemeGroupVersion.WithResource("cronjobs")) {
-		return fmt.Errorf("CronJob generator specified, but batch/v2alpha1.CronJobs are not available")
-	}
+	generatorName = cmdutil.FallbackGeneratorNameIfNecessary(generatorName, resourcesList, cmdErr)
 
 	generators := f.Generators("run")
 	generator, found := generators[generatorName]
@@ -407,14 +398,6 @@ func RunRun(f cmdutil.Factory, cmdIn io.Reader, cmdOut, cmdErr io.Writer, cmd *c
 	return nil
 }
 
-// TODO turn this into reusable method checking available resources
-func contains(resourcesList []*metav1.APIResourceList, resource schema.GroupVersionResource) bool {
-	resources := discovery.FilteredBy(discovery.ResourcePredicateFunc(func(gv string, r *metav1.APIResource) bool {
-		return resource.GroupVersion().String() == gv && resource.Resource == r.Name
-	}), resourcesList)
-	return len(resources) != 0
-}
-
 // waitForPod watches the given pod until the exitCondition is true
 func waitForPod(podClient coreclient.PodsGetter, ns, name string, exitCondition watch.ConditionFunc) (*api.Pod, error) {
 	w, err := podClient.Pods(ns).Watch(metav1.SingleObject(metav1.ObjectMeta{Name: name}))

pkg/kubectl/cmd/util/BUILD

@@ -47,6 +47,8 @@ go_library(
         "//vendor/github.com/googleapis/gnostic/OpenAPIv2:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",
         "//vendor/github.com/spf13/pflag:go_default_library",
+        "//vendor/k8s.io/api/apps/v1beta1:go_default_library",
+        "//vendor/k8s.io/api/batch/v2alpha1:go_default_library",
         "//vendor/k8s.io/api/core/v1:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/meta:go_default_library",

pkg/kubectl/cmd/util/factory_client_access.go

@@ -32,7 +32,10 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 
+	appsv1beta1 "k8s.io/api/apps/v1beta1"
+	batchv2alpha1 "k8s.io/api/batch/v2alpha1"
 	"k8s.io/apimachinery/pkg/api/meta"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	utilflag "k8s.io/apiserver/pkg/util/flag"
@@ -571,6 +574,50 @@ func DefaultGenerators(cmdName string) map[string]kubectl.Generator {
 	return generator
 }
 
+// fallbackGeneratorNameIfNecessary returns the name of the old generator
+// if server does not support new generator. Otherwise, the
+// generator string is returned unchanged.
+//
+// If the generator name is changed, print a warning message to let the user
+// know.
+func FallbackGeneratorNameIfNecessary(
+	generatorName string,
+	resourcesList []*metav1.APIResourceList,
+	cmdErr io.Writer,
+) string {
+	switch generatorName {
+	case DeploymentBasicAppsV1Beta1GeneratorName:
+		if !Contains(resourcesList, appsv1beta1.SchemeGroupVersion.WithResource("deployments")) {
+			warning(cmdErr, DeploymentBasicAppsV1Beta1GeneratorName, DeploymentBasicV1Beta1GeneratorName)
+
+			return DeploymentBasicV1Beta1GeneratorName
+		}
+	case CronJobV2Alpha1GeneratorName:
+		if !Contains(resourcesList, batchv2alpha1.SchemeGroupVersion.WithResource("cronjobs")) {
+			warning(cmdErr, CronJobV2Alpha1GeneratorName, JobV1GeneratorName)
+
+			return JobV1GeneratorName
+		}
+	}
+	return generatorName
+}
+
+func warning(cmdErr io.Writer, newGeneratorName, oldGeneratorName string) {
+	fmt.Fprintf(cmdErr, "WARNING: New deployments generator %q specified, "+
+		"but it isn't available. "+
+		"Falling back to %q.\n",
+		newGeneratorName,
+		oldGeneratorName,
+	)
+}
+
+func Contains(resourcesList []*metav1.APIResourceList, resource schema.GroupVersionResource) bool {
+	resources := discovery.FilteredBy(discovery.ResourcePredicateFunc(func(gv string, r *metav1.APIResource) bool {
+		return resource.GroupVersion().String() == gv && resource.Resource == r.Name
+	}), resourcesList)
+	return len(resources) != 0
+}
+
 func (f *ring0Factory) Generators(cmdName string) map[string]kubectl.Generator {
 	return DefaultGenerators(cmdName)
 }