add kubectl api-resources command

docs/.generated_docs

@@ -135,6 +135,7 @@ docs/man/man1/kubeadm.1
 docs/man/man1/kubectl-alpha-diff.1
 docs/man/man1/kubectl-alpha.1
 docs/man/man1/kubectl-annotate.1
+docs/man/man1/kubectl-api-resources.1
 docs/man/man1/kubectl-api-versions.1
 docs/man/man1/kubectl-apply-edit-last-applied.1
 docs/man/man1/kubectl-apply-set-last-applied.1
@@ -234,6 +235,7 @@ docs/user-guide/kubectl/kubectl.md
 docs/user-guide/kubectl/kubectl_alpha.md
 docs/user-guide/kubectl/kubectl_alpha_diff.md
 docs/user-guide/kubectl/kubectl_annotate.md
+docs/user-guide/kubectl/kubectl_api-resources.md
 docs/user-guide/kubectl/kubectl_api-versions.md
 docs/user-guide/kubectl/kubectl_apply.md
 docs/user-guide/kubectl/kubectl_apply_edit-last-applied.md
@@ -329,6 +331,7 @@ docs/user-guide/kubectl/kubectl_version.md
 docs/yaml/kubectl/kubectl.yaml
 docs/yaml/kubectl/kubectl_alpha.yaml
 docs/yaml/kubectl/kubectl_annotate.yaml
+docs/yaml/kubectl/kubectl_api-resources.yaml
 docs/yaml/kubectl/kubectl_api-versions.yaml
 docs/yaml/kubectl/kubectl_apply.yaml
 docs/yaml/kubectl/kubectl_attach.yaml

docs/man/man1/kubectl-api-resources.1

+This file is autogenerated, but we've stopped checking such files into the
+repository to reduce the need for rebases. Please run hack/generate-docs.sh to
+populate this file.

docs/user-guide/kubectl/kubectl_api-resources.md

+This file is autogenerated, but we've stopped checking such files into the
+repository to reduce the need for rebases. Please run hack/generate-docs.sh to
+populate this file.

docs/yaml/kubectl/kubectl_api-resources.yaml

+This file is autogenerated, but we've stopped checking such files into the
+repository to reduce the need for rebases. Please run hack/generate-docs.sh to
+populate this file.

hack/make-rules/test-cmd-util.sh

@@ -4663,6 +4663,8 @@ runTests() {
   # Cluster Role #
   ################
 
+  kubectl "${kube_flags[@]}" api-resources
+
   if kube::test::if_supports_resource "${clusterroles}" ; then
     record_command run_clusterroles_tests
   fi

pkg/kubectl/cmd/BUILD

@@ -9,6 +9,7 @@ go_library(
     srcs = [
         "alpha.go",
         "annotate.go",
+        "apiresources.go",
         "apiversions.go",
         "apply.go",
         "apply_edit_last_applied.go",

pkg/kubectl/cmd/apiresources.go

+/*
+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 cmd
+
+import (
+	"fmt"
+	"io"
+	"sort"
+	"strings"
+
+	"github.com/spf13/cobra"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+	"k8s.io/kubernetes/pkg/printers"
+)
+
+var (
+	apiresources_example = templates.Examples(`
+		# Print the supported API Resources
+		kubectl api-resources
+
+		# Print the supported API Resources with more information
+		kubectl api-resources -o wide
+
+		# Print the supported namespaced resources
+		kubectl api-resources --namespaced=true
+
+		# Print the supported non-namespaced resources
+		kubectl api-resources --namespaced=false
+
+		# Print the supported API Resources with specific APIGroup
+		kubectl api-resources --api-group=extensions`)
+)
+
+// ApiResourcesOptions is the start of the data required to perform the operation.  As new fields are added, add them here instead of
+// referencing the cmd.Flags()
+type ApiResourcesOptions struct {
+	out io.Writer
+
+	Output     string
+	APIGroup   string
+	Namespaced bool
+	NoHeaders  bool
+}
+
+// groupResource contains the APIGroup and APIResource
+type groupResource struct {
+	APIGroup    string
+	APIResource metav1.APIResource
+}
+
+func NewCmdApiResources(f cmdutil.Factory, out io.Writer) *cobra.Command {
+	options := &ApiResourcesOptions{
+		out: out,
+	}
+
+	cmd := &cobra.Command{
+		Use:     "api-resources",
+		Short:   "Print the supported API resources on the server",
+		Long:    "Print the supported API resources on the server",
+		Example: apiresources_example,
+		Run: func(cmd *cobra.Command, args []string) {
+			cmdutil.CheckErr(options.Complete(cmd))
+			cmdutil.CheckErr(options.Validate(cmd))
+			cmdutil.CheckErr(options.RunApiResources(cmd, f))
+		},
+	}
+	cmdutil.AddOutputFlags(cmd)
+	cmdutil.AddNoHeadersFlags(cmd)
+	cmd.Flags().StringVar(&options.APIGroup, "api-group", "", "The API group to use when talking to the server.")
+	cmd.Flags().BoolVar(&options.Namespaced, "namespaced", true, "Namespaced indicates if a resource is namespaced or not.")
+	return cmd
+}
+
+func (o *ApiResourcesOptions) Complete(cmd *cobra.Command) error {
+	o.Output = cmdutil.GetFlagString(cmd, "output")
+	o.NoHeaders = cmdutil.GetFlagBool(cmd, "no-headers")
+	return nil
+}
+
+func (o *ApiResourcesOptions) Validate(cmd *cobra.Command) error {
+	validOutputTypes := sets.NewString("", "json", "yaml", "wide", "name", "custom-columns", "custom-columns-file", "go-template", "go-template-file", "jsonpath", "jsonpath-file")
+	supportedOutputTypes := sets.NewString("", "wide")
+	outputFormat := cmdutil.GetFlagString(cmd, "output")
+	if !validOutputTypes.Has(outputFormat) {
+		return fmt.Errorf("output must be one of '' or 'wide': %v", outputFormat)
+	}
+	if !supportedOutputTypes.Has(outputFormat) {
+		return fmt.Errorf("--output %v is not available in kubectl api-resources", outputFormat)
+	}
+	return nil
+}
+
+func (o *ApiResourcesOptions) RunApiResources(cmd *cobra.Command, f cmdutil.Factory) error {
+	w := printers.GetNewTabWriter(o.out)
+	defer w.Flush()
+
+	discoveryclient, err := f.DiscoveryClient()
+	if err != nil {
+		return err
+	}
+
+	// Always request fresh data from the server
+	discoveryclient.Invalidate()
+
+	lists, err := discoveryclient.ServerPreferredResources()
+	if err != nil {
+		return err
+	}
+
+	resources := []groupResource{}
+
+	groupChanged := cmd.Flags().Changed("api-group")
+	nsChanged := cmd.Flags().Changed("namespaced")
+
+	for _, list := range lists {
+		if len(list.APIResources) == 0 {
+			continue
+		}
+		gv, err := schema.ParseGroupVersion(list.GroupVersion)
+		if err != nil {
+			continue
+		}
+		for _, resource := range list.APIResources {
+			if len(resource.Verbs) == 0 {
+				continue
+			}
+			// filter apiGroup
+			if groupChanged && o.APIGroup != gv.Group {
+				continue
+			}
+			// filter namespaced
+			if nsChanged && o.Namespaced != resource.Namespaced {
+				continue
+			}
+			resources = append(resources, groupResource{
+				APIGroup:    gv.Group,
+				APIResource: resource,
+			})
+		}
+	}
+
+	if o.NoHeaders == false {
+		if err = printContextHeaders(w, o.Output); err != nil {
+			return err
+		}
+	}
+
+	sort.Stable(sortableGroupResource(resources))
+	for _, r := range resources {
+		if o.Output == "wide" {
+			if _, err := fmt.Fprintf(w, "%s\t%s\t%s\t%v\t%s\t%v\n",
+				r.APIResource.Name,
+				strings.Join(r.APIResource.ShortNames, ","),
+				r.APIGroup,
+				r.APIResource.Namespaced,
+				r.APIResource.Kind,
+				r.APIResource.Verbs); err != nil {
+				return err
+			}
+		} else {
+			if _, err := fmt.Fprintf(w, "%s\t%s\t%s\t%v\t%s\n",
+				r.APIResource.Name,
+				strings.Join(r.APIResource.ShortNames, ","),
+				r.APIGroup,
+				r.APIResource.Namespaced,
+				r.APIResource.Kind); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func printContextHeaders(out io.Writer, output string) error {
+	columnNames := []string{"NAME", "SHORTNAMES", "APIGROUP", "NAMESPACED", "KIND"}
+	if output == "wide" {
+		columnNames = append(columnNames, "VERBS")
+	}
+	_, err := fmt.Fprintf(out, "%s\n", strings.Join(columnNames, "\t"))
+	return err
+}
+
+type sortableGroupResource []groupResource
+
+func (s sortableGroupResource) Len() int      { return len(s) }
+func (s sortableGroupResource) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+func (s sortableGroupResource) Less(i, j int) bool {
+	ret := strings.Compare(s[i].APIGroup, s[j].APIGroup)
+	if ret > 0 {
+		return false
+	} else if ret == 0 {
+		return strings.Compare(s[i].APIResource.Name, s[j].APIResource.Name) < 0
+	}
+	return true
+}

pkg/kubectl/cmd/cmd.go

@@ -346,6 +346,7 @@ func NewKubectlCommand(f cmdutil.Factory, in io.Reader, out, err io.Writer) *cob
 	cmds.AddCommand(NewCmdPlugin(f, in, out, err))
 	cmds.AddCommand(NewCmdVersion(f, out))
 	cmds.AddCommand(NewCmdApiVersions(f, out))
+	cmds.AddCommand(NewCmdApiResources(f, out))
 	cmds.AddCommand(NewCmdOptions(out))
 
 	return cmds