Added support for yaml ouptut in docs gen (#380)

Signed-off-by: French Ben <frenchben@docker.com>

doc/md_docs.md

@@ -32,15 +32,15 @@ import (
 	"io/ioutil"
 	"os"
 
-	kubectlcmd "k8s.io/kubernetes/pkg/kubectl/cmd"
+	"k8s.io/kubernetes/pkg/kubectl/cmd"
 	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
 
 	"github.com/spf13/cobra/doc"
 )
 
 func main() {
-	cmd := kubectlcmd.NewKubectlCommand(cmdutil.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard)
+	kubectl := cmd.NewKubectlCommand(cmdutil.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard)
-	doc.GenMarkdownTree(cmd, "./")
+	doc.GenMarkdownTree(kubectl, "./")
 }
 ```
 

doc/util.go

@@ -13,7 +13,11 @@
 
 package doc
 
-import "github.com/spf13/cobra"
+import (
+	"strings"
+
+	"github.com/spf13/cobra"
+)
 
 // Test to see if we have a reason to print See Also information in docs
 // Basically this is a test for a parent commend or a subcommand which is
@@ -31,6 +35,15 @@ func hasSeeAlso(cmd *cobra.Command) bool {
 	return false
 }
 
+// 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
+}
+
 type byName []*cobra.Command
 
 func (s byName) Len() int           { return len(s) }

doc/yaml_docs.go

@@ -0,0 +1,165 @@
+// Copyright 2016 French Ben. 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 doc
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+	"gopkg.in/yaml.v2"
+)
+
+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"`
+}
+
+// GenYamlTree creates yaml structured ref files for this command and all descendants
+// in the directory given. This function may not work
+// correctly if your command names have - in them. If you have `cmd` with two
+// subcmds, `sub` and `sub-third`. And `sub` has a subcommand called `third`
+// it is undefined which help output will be in the file `cmd-sub-third.1`.
+func GenYamlTree(cmd *cobra.Command, dir string) error {
+	identity := func(s string) string { return s }
+	emptyStr := func(s string) string { return "" }
+	return GenYamlTreeCustom(cmd, dir, emptyStr, identity)
+}
+
+// GenYamlTreeCustom creates yaml structured ref files
+func GenYamlTreeCustom(cmd *cobra.Command, dir string, filePrepender, linkHandler func(string) string) error {
+	for _, c := range cmd.Commands() {
+		if !c.IsAvailableCommand() || c.IsHelpCommand() {
+			continue
+		}
+		if err := GenYamlTreeCustom(c, dir, filePrepender, linkHandler); err != nil {
+			return err
+		}
+	}
+
+	basename := strings.Replace(cmd.CommandPath(), " ", "_", -1) + ".yaml"
+	filename := filepath.Join(dir, basename)
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if _, err := io.WriteString(f, filePrepender(filename)); err != nil {
+		return err
+	}
+	if err := GenYamlCustom(cmd, f, linkHandler); err != nil {
+		return err
+	}
+	return nil
+}
+
+// GenYaml creates yaml output
+func GenYaml(cmd *cobra.Command, w io.Writer) error {
+	return GenYamlCustom(cmd, w, func(s string) string { return s })
+}
+
+// GenYamlCustom creates custom yaml output
+func GenYamlCustom(cmd *cobra.Command, w io.Writer, linkHandler func(string) string) error {
+	yamlDoc := cmdDoc{}
+	yamlDoc.Name = cmd.CommandPath()
+
+	yamlDoc.Synopsis = forceMultiLine(cmd.Short)
+	yamlDoc.Description = forceMultiLine(cmd.Long)
+
+	if len(cmd.Example) > 0 {
+		yamlDoc.Example = cmd.Example
+	}
+
+	flags := cmd.NonInheritedFlags()
+	if flags.HasFlags() {
+		yamlDoc.Options = genFlagResult(flags)
+	}
+	flags = cmd.InheritedFlags()
+	if flags.HasFlags() {
+		yamlDoc.InheritedOptions = genFlagResult(flags)
+	}
+
+	if hasSeeAlso(cmd) {
+		result := []string{}
+		if cmd.HasParent() {
+			parent := cmd.Parent()
+			result = append(result, parent.CommandPath()+" - "+parent.Short)
+		}
+		children := cmd.Commands()
+		sort.Sort(byName(children))
+		for _, child := range children {
+			if !child.IsAvailableCommand() || child.IsHelpCommand() {
+				continue
+			}
+			result = append(result, child.Name()+" - "+child.Short)
+		}
+		yamlDoc.SeeAlso = result
+	}
+
+	final, err := yaml.Marshal(&yamlDoc)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if _, err := fmt.Fprintf(w, string(final)); err != nil {
+		return err
+	}
+	return nil
+}
+
+func genFlagResult(flags *pflag.FlagSet) []cmdOption {
+	var result []cmdOption
+
+	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
+}

doc/yaml_docs.md

@@ -0,0 +1,103 @@
+# Generating Yaml Docs For Your Own cobra.Command
+
+Generating yaml files from a cobra command is incredibly easy. An example is as follows:
+
+```go
+package main
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	cmd := &cobra.Command{
+		Use:   "test",
+		Short: "my test program",
+	}
+	doc.GenYamlTree(cmd, "/tmp")
+}
+```
+
+That will get you a Yaml document `/tmp/test.yaml`
+
+## Generate yaml docs for the entire command tree
+
+This program can actually generate docs for the kubectl command in the kubernetes project
+
+```go
+package main
+
+import (
+	"io/ioutil"
+	"os"
+
+	"k8s.io/kubernetes/pkg/kubectl/cmd"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	kubectl := cmd.NewKubectlCommand(cmdutil.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard)
+	doc.GenYamlTree(kubectl, "./")
+}
+```
+
+This will generate a whole series of files, one for each command in the tree, in the directory specified (in this case "./")
+
+## Generate yaml docs for a single command
+
+You may wish to have more control over the output, or only generate for a single command, instead of the entire command tree. If this is the case you may prefer to `GenYaml` instead of `GenYamlTree`
+
+```go
+	out := new(bytes.Buffer)
+	doc.GenYaml(cmd, out)
+```
+
+This will write the yaml doc for ONLY "cmd" into the out, buffer.
+
+## Customize the output
+
+Both `GenYaml` and `GenYamlTree` have alternate versions with callbacks to get some control of the output:
+
+```go
+func GenYamlTreeCustom(cmd *Command, dir string, filePrepender, linkHandler func(string) string) error {
+	//...
+}
+```
+
+```go
+func GenYamlCustom(cmd *Command, out *bytes.Buffer, linkHandler func(string) string) error {
+	//...
+}
+```
+
+The `filePrepender` will prepend the return value given the full filepath to the rendered Yaml file. A common use case is to add front matter to use the generated documentation with [Hugo](http://gohugo.io/):
+
+```go
+const fmTemplate = `---
+date: %s
+title: "%s"
+slug: %s
+url: %s
+---
+`
+
+filePrepender := func(filename string) string {
+	now := time.Now().Format(time.RFC3339)
+	name := filepath.Base(filename)
+	base := strings.TrimSuffix(name, path.Ext(name))
+	url := "/commands/" + strings.ToLower(base) + "/"
+	return fmt.Sprintf(fmTemplate, now, strings.Replace(base, "_", " ", -1), base, url)
+}
+```
+
+The `linkHandler` can be used to customize the rendered internal links to the commands, given a filename:
+
+```go
+linkHandler := func(name string) string {
+	base := strings.TrimSuffix(name, path.Ext(name))
+	return "/commands/" + strings.ToLower(base) + "/"
+}
+```

doc/yaml_docs_test.go

@@ -0,0 +1,88 @@
+package doc
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"strings"
+	"testing"
+)
+
+var _ = fmt.Println
+var _ = os.Stderr
+
+func TestGenYamlDoc(t *testing.T) {
+	c := initializeWithRootCmd()
+	// Need two commands to run the command alphabetical sort
+	cmdEcho.AddCommand(cmdTimes, cmdEchoSub, cmdDeprecated)
+	c.AddCommand(cmdPrint, cmdEcho)
+	cmdRootWithRun.PersistentFlags().StringVarP(&flags2a, "rootflag", "r", "two", strtwoParentHelp)
+
+	out := new(bytes.Buffer)
+
+	// We generate on s subcommand so we have both subcommands and parents
+	if err := GenYaml(cmdEcho, out); err != nil {
+		t.Fatal(err)
+	}
+	found := out.String()
+
+	// Our description
+	expected := cmdEcho.Long
+	if !strings.Contains(found, expected) {
+		t.Errorf("Unexpected response.\nExpecting to contain: \n %q\nGot:\n %q\n", expected, found)
+	}
+
+	// Better have our example
+	expected = cmdEcho.Example
+	if !strings.Contains(found, expected) {
+		t.Errorf("Unexpected response.\nExpecting to contain: \n %q\nGot:\n %q\n", expected, found)
+	}
+
+	// A local flag
+	expected = "boolone"
+	if !strings.Contains(found, expected) {
+		t.Errorf("Unexpected response.\nExpecting to contain: \n %q\nGot:\n %q\n", expected, found)
+	}
+
+	// persistent flag on parent
+	expected = "rootflag"
+	if !strings.Contains(found, expected) {
+		t.Errorf("Unexpected response.\nExpecting to contain: \n %q\nGot:\n %q\n", expected, found)
+	}
+
+	// We better output info about our parent
+	expected = cmdRootWithRun.Short
+	if !strings.Contains(found, expected) {
+		t.Errorf("Unexpected response.\nExpecting to contain: \n %q\nGot:\n %q\n", expected, found)
+	}
+
+	// And about subcommands
+	expected = cmdEchoSub.Short
+	if !strings.Contains(found, expected) {
+		t.Errorf("Unexpected response.\nExpecting to contain: \n %q\nGot:\n %q\n", expected, found)
+	}
+
+	unexpected := cmdDeprecated.Short
+	if strings.Contains(found, unexpected) {
+		t.Errorf("Unexpected response.\nFound: %v\nBut should not have!!\n", unexpected)
+	}
+}
+
+func TestGenYamlNoTag(t *testing.T) {
+	c := initializeWithRootCmd()
+	// Need two commands to run the command alphabetical sort
+	cmdEcho.AddCommand(cmdTimes, cmdEchoSub, cmdDeprecated)
+	c.AddCommand(cmdPrint, cmdEcho)
+	c.DisableAutoGenTag = true
+	cmdRootWithRun.PersistentFlags().StringVarP(&flags2a, "rootflag", "r", "two", strtwoParentHelp)
+	out := new(bytes.Buffer)
+
+	if err := GenYaml(c, out); err != nil {
+		t.Fatal(err)
+	}
+	found := out.String()
+
+	unexpected := "Auto generated"
+	checkStringOmits(t, found, unexpected)
+
+}