Create cmd to generate kubectl yaml docs

cmd/genyaml/gen_kubectl_yaml.go

@@ -0,0 +1,169 @@
+/*
+Copyright 2014 The Kubernetes Authors All rights reserved.
+
+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 main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+	"gopkg.in/yaml.v2"
+	"k8s.io/kubernetes/cmd/genutils"
+	"k8s.io/kubernetes/pkg/kubectl/cmd"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+)
+
+type cmdOption struct {
+	Name         string
+	Shorthand    string `yaml:",omitempty"`
+	DefaultValue string `yaml:"default_value,omitempty"`
+	Usage        string `yaml:",omitempty"`
+}
+
+type cmdDoc struct {
+	Name             string
+	Synopsis         string      `yaml:",omitempty"`
+	Description      string      `yaml:",omitempty"`
+	Options          []cmdOption `yaml:",omitempty"`
+	InheritedOptions []cmdOption `yaml:"inherited_options,omitempty"`
+	Example          string      `yaml:",omitempty"`
+	SeeAlso          []string    `yaml:"see_also,omitempty"`
+}
+
+func main() {
+	path := "docs/yaml/kubectl"
+	if len(os.Args) == 2 {
+		path = os.Args[1]
+	} else if len(os.Args) > 2 {
+		fmt.Fprintf(os.Stderr, "usage: %s [output directory]\n", os.Args[0])
+		os.Exit(1)
+	}
+
+	outDir, err := genutils.OutDir(path)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to get output directory: %v\n", err)
+		os.Exit(1)
+	}
+
+	// Set environment variables used by kubectl so the output is consistent,
+	// regardless of where we run.
+	os.Setenv("HOME", "/home/username")
+	// TODO os.Stdin should really be something like ioutil.Discard, but a Reader
+	kubectl := cmd.NewKubectlCommand(cmdutil.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard)
+	genYaml(kubectl, "", outDir)
+	for _, c := range kubectl.Commands() {
+		genYaml(c, "kubectl", outDir)
+	}
+}
+
+// Temporary workaround for yaml lib generating incorrect yaml with long strings
+// that do not contain \n.
+func forceMultiLine(s string) string {
+	if len(s) > 60 && !strings.Contains(s, "\n") {
+		s = s + "\n"
+	}
+	return s
+}
+
+func genFlagResult(flags *pflag.FlagSet) []cmdOption {
+	result := make([]cmdOption, 0)
+
+	flags.VisitAll(func(flag *pflag.Flag) {
+		// Todo, when we mark a shorthand is deprecated, but specify an empty message.
+		// The flag.ShorthandDeprecated is empty as the shorthand is deprecated.
+		// Using len(flag.ShorthandDeprecated) > 0 can't handle this, others are ok.
+		if !(len(flag.ShorthandDeprecated) > 0) && len(flag.Shorthand) > 0 {
+			opt := cmdOption{
+				flag.Name,
+				flag.Shorthand,
+				flag.DefValue,
+				forceMultiLine(flag.Usage),
+			}
+			result = append(result, opt)
+		} else {
+			opt := cmdOption{
+				Name:         flag.Name,
+				DefaultValue: forceMultiLine(flag.DefValue),
+				Usage:        forceMultiLine(flag.Usage),
+			}
+			result = append(result, opt)
+		}
+	})
+
+	return result
+}
+
+func genYaml(command *cobra.Command, parent, docsDir string) {
+	doc := cmdDoc{}
+
+	doc.Name = command.Name()
+	doc.Synopsis = forceMultiLine(command.Short)
+	doc.Description = forceMultiLine(command.Long)
+
+	flags := command.NonInheritedFlags()
+	if flags.HasFlags() {
+		doc.Options = genFlagResult(flags)
+	}
+	flags = command.InheritedFlags()
+	if flags.HasFlags() {
+		doc.InheritedOptions = genFlagResult(flags)
+	}
+
+	if len(command.Example) > 0 {
+		doc.Example = command.Example
+	}
+
+	if len(command.Commands()) > 0 || len(parent) > 0 {
+		result := make([]string, 0)
+		if len(parent) > 0 {
+			result = append(result, parent)
+		}
+		for _, c := range command.Commands() {
+			result = append(result, c.Name())
+		}
+		doc.SeeAlso = result
+	}
+
+	final, err := yaml.Marshal(&doc)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	var filename string
+
+	if parent == "" {
+		filename = docsDir + doc.Name + ".yaml"
+	} else {
+		filename = docsDir + parent + "_" + doc.Name + ".yaml"
+	}
+
+	outFile, err := os.Create(filename)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	defer outFile.Close()
+	_, err = outFile.Write(final)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}