cmd: Migrate to spf13/cobra, remove single-dash arg support

cmd/cobra.go

@@ -0,0 +1,33 @@
+package caddycmd
+
+import (
+	"github.com/spf13/cobra"
+)
+
+var rootCmd = &cobra.Command{
+	Use: "caddy",
+}
+
+const docsHeader = `Caddy is an extensible server platform.`
+const fullDocsFooter = `Full documentation is available at:
+https://caddyserver.com/docs/command-line
+`
+
+func init() {
+	rootCmd.SetHelpTemplate(docsHeader + "\n\n" + rootCmd.HelpTemplate() + "\n" + fullDocsFooter)
+}
+
+func caddyCmdToCoral(caddyCmd Command) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   caddyCmd.Name,
+		Short: caddyCmd.Short,
+		Long:  caddyCmd.Long,
+		RunE: func(cmd *cobra.Command, _ []string) error {
+			fls := cmd.Flags()
+			_, err := caddyCmd.Func(Flags{fls})
+			return err
+		},
+	}
+	cmd.Flags().AddGoFlagSet(caddyCmd.Flags)
+	return cmd
+}

cmd/commandfuncs.go

@@ -29,7 +29,6 @@ import (
 	"os/exec"
 	"runtime"
 	"runtime/debug"
-	"sort"
 	"strings"
 
 	"github.com/aryann/difflib"
@@ -580,70 +579,6 @@ func cmdFmt(fl Flags) (int, error) {
 	return caddy.ExitCodeSuccess, nil
 }
 
-func cmdHelp(fl Flags) (int, error) {
-	const fullDocs = `Full documentation is available at:
-https://caddyserver.com/docs/command-line`
-
-	args := fl.Args()
-	if len(args) == 0 {
-		s := `Caddy is an extensible server platform.
-
-usage:
-  caddy <command> [<args...>]
-
-commands:
-`
-		keys := make([]string, 0, len(commands))
-		for k := range commands {
-			keys = append(keys, k)
-		}
-		sort.Strings(keys)
-		for _, k := range keys {
-			cmd := commands[k]
-			short := strings.TrimSuffix(cmd.Short, ".")
-			s += fmt.Sprintf("  %-15s %s\n", cmd.Name, short)
-		}
-
-		s += "\nUse 'caddy help <command>' for more information about a command.\n"
-		s += "\n" + fullDocs + "\n"
-
-		fmt.Print(s)
-
-		return caddy.ExitCodeSuccess, nil
-	} else if len(args) > 1 {
-		return caddy.ExitCodeFailedStartup, fmt.Errorf("can only give help with one command")
-	}
-
-	subcommand, ok := commands[args[0]]
-	if !ok {
-		return caddy.ExitCodeFailedStartup, fmt.Errorf("unknown command: %s", args[0])
-	}
-
-	helpText := strings.TrimSpace(subcommand.Long)
-	if helpText == "" {
-		helpText = subcommand.Short
-		if !strings.HasSuffix(helpText, ".") {
-			helpText += "."
-		}
-	}
-
-	result := fmt.Sprintf("%s\n\nusage:\n  caddy %s %s\n",
-		helpText,
-		subcommand.Name,
-		strings.TrimSpace(subcommand.Usage),
-	)
-
-	if help := flagHelp(subcommand.Flags); help != "" {
-		result += fmt.Sprintf("\nflags: (NOTE: prefix flags with `--` instead of `-`)\n%s", help)
-	}
-
-	result += "\n" + fullDocs + "\n"
-
-	fmt.Print(result)
-
-	return caddy.ExitCodeSuccess, nil
-}
-
 // AdminAPIRequest makes an API request according to the CLI flags given,
 // with the given HTTP method and request URI. If body is non-nil, it will
 // be assumed to be Content-Type application/json. The caller should close

cmd/commands.go

@@ -16,7 +16,13 @@ package caddycmd
 
 import (
 	"flag"
+	"fmt"
+	"os"
 	"regexp"
+	"strings"
+
+	"github.com/caddyserver/caddy/v2"
+	"github.com/spf13/cobra/doc"
 )
 
 // Command represents a subcommand. Name, Func,
@@ -70,13 +76,6 @@ func Commands() map[string]Command {
 var commands = make(map[string]Command)
 
 func init() {
-	RegisterCommand(Command{
-		Name:  "help",
-		Func:  cmdHelp,
-		Usage: "<command>",
-		Short: "Shows help for a Caddy subcommand",
-	})
-
 	RegisterCommand(Command{
 		Name:  "start",
 		Func:  cmdStart,
@@ -346,6 +345,41 @@ EXPERIMENTAL: May be changed or removed.
 		}(),
 	})
 
+	RegisterCommand(Command{
+		Name: "manpage",
+		Func: func(fl Flags) (int, error) {
+			dir := strings.TrimSpace(fl.String("directory"))
+			section := strings.TrimSpace(fl.String("section"))
+			if dir == "" || section == "" {
+				return caddy.ExitCodeFailedQuit, fmt.Errorf("designated output directory and specified section are required")
+			}
+			if err := os.MkdirAll(dir, 0755); err != nil {
+				return caddy.ExitCodeFailedQuit, err
+			}
+			if err := doc.GenManTree(rootCmd, &doc.GenManHeader{
+				Title:   "Caddy",
+				Section: section,
+			}, dir); err != nil {
+				return caddy.ExitCodeFailedQuit, err
+			}
+			return caddy.ExitCodeSuccess, nil
+		},
+		Usage: "--directory <directory path> --section <section number>",
+		Short: "Generates the manual pages of Caddy commands",
+		Long: `
+Generates the manual pages of Caddy commands into the designated directory tagged into the specified section.
+
+The manual page files are generated into the directory specified by the argument of --directory. If the directory does not exist, it will be created.
+
+The manual pages are sorted into the section specified by the argument of --section.
+`,
+		Flags: func() *flag.FlagSet {
+			fs := flag.NewFlagSet("manpage", flag.ExitOnError)
+			fs.String("directory", "", "The output directory where the manpages are generated")
+			fs.String("section", "", "The section number of the generated manual pages")
+			return fs
+		}(),
+	})
 }
 
 // RegisterCommand registers the command cmd.
@@ -378,7 +412,7 @@ func RegisterCommand(cmd Command) {
 	if !commandNameRegex.MatchString(cmd.Name) {
 		panic("invalid command name")
 	}
-	commands[cmd.Name] = cmd
+	rootCmd.AddCommand(caddyCmdToCoral(cmd))
 }
 
 var commandNameRegex = regexp.MustCompile(`^[a-z0-9]$|^([a-z0-9]+-?[a-z0-9]*)+[a-z0-9]$`)

cmd/main.go

@@ -33,6 +33,7 @@ import (
 	"github.com/caddyserver/caddy/v2"
 	"github.com/caddyserver/caddy/v2/caddyconfig"
 	"github.com/caddyserver/certmagic"
+	"github.com/spf13/pflag"
 	"go.uber.org/zap"
 )
 
@@ -58,35 +59,9 @@ func Main() {
 		os.Args = append(os.Args, "help")
 	}
 
-	subcommandName := os.Args[1]
-	subcommand, ok := commands[subcommandName]
-	if !ok {
-		if strings.HasPrefix(os.Args[1], "-") {
-			// user probably forgot to type the subcommand
-			fmt.Println("[ERROR] first argument must be a subcommand; see 'caddy help'")
-		} else {
-			fmt.Printf("[ERROR] '%s' is not a recognized subcommand; see 'caddy help'\n", os.Args[1])
-		}
-		os.Exit(caddy.ExitCodeFailedStartup)
-	}
-
-	fs := subcommand.Flags
-	if fs == nil {
-		fs = flag.NewFlagSet(subcommand.Name, flag.ExitOnError)
+	if err := rootCmd.Execute(); err != nil {
+		os.Exit(1)
 	}
-
-	err := fs.Parse(os.Args[2:])
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(caddy.ExitCodeFailedStartup)
-	}
-
-	exitCode, err := subcommand.Func(Flags{fs})
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "%s: %v\n", subcommand.Name, err)
-	}
-
-	os.Exit(exitCode)
 }
 
 // handlePingbackConn reads from conn and ensures it matches
@@ -280,7 +255,7 @@ func watchConfigFile(filename, adapterName string) {
 // Flags wraps a FlagSet so that typed values
 // from flags can be easily retrieved.
 type Flags struct {
-	*flag.FlagSet
+	*pflag.FlagSet
 }
 
 // String returns the string representation of the
@@ -326,22 +301,6 @@ func (f Flags) Duration(name string) time.Duration {
 	return val
 }
 
-// flagHelp returns the help text for fs.
-func flagHelp(fs *flag.FlagSet) string {
-	if fs == nil {
-		return ""
-	}
-
-	// temporarily redirect output
-	out := fs.Output()
-	defer fs.SetOutput(out)
-
-	buf := new(bytes.Buffer)
-	fs.SetOutput(buf)
-	fs.PrintDefaults()
-	return buf.String()
-}
-
 func loadEnvFromFile(envFile string) error {
 	file, err := os.Open(envFile)
 	if err != nil {
@@ -470,5 +429,9 @@ func (ss *StringSlice) Set(value string) error {
 	return nil
 }
 
+// TODO: should it implement either of those?
+// var _ pflag.Value = (*StringSlice)(nil)
+// var _ pflag.SliceValue = (*StringSlice)(nil)
+
 // Interface guard
 var _ flag.Value = (*StringSlice)(nil)

go.mod

@@ -21,6 +21,8 @@ require (
 	github.com/smallstep/cli v0.21.0
 	github.com/smallstep/nosql v0.4.0
 	github.com/smallstep/truststore v0.11.0
+	github.com/spf13/cobra v1.1.3
+	github.com/spf13/pflag v1.0.5
 	github.com/tailscale/tscert v0.0.0-20220316030059-54bbcb9f74e2
 	github.com/yuin/goldmark v1.4.13
 	github.com/yuin/goldmark-highlighting v0.0.0-20220208100518-594be1970594
@@ -40,6 +42,7 @@ require (
 require (
 	github.com/golang/mock v1.6.0 // indirect
 	golang.org/x/exp v0.0.0-20220722155223-a9213eeb770e // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
 )
 
 require (
@@ -53,7 +56,7 @@ require (
 	github.com/cespare/xxhash v1.1.0 // indirect
 	github.com/cespare/xxhash/v2 v2.1.2 // indirect
 	github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e // indirect
-	github.com/cpuguy83/go-md2man/v2 v2.0.0 // indirect
+	github.com/cpuguy83/go-md2man/v2 v2.0.1 // indirect
 	github.com/dgraph-io/badger v1.6.2 // indirect
 	github.com/dgraph-io/badger/v2 v2.2007.4 // indirect
 	github.com/dgraph-io/ristretto v0.0.4-0.20200906165740-41ebdbffecfd // indirect
@@ -72,6 +75,7 @@ require (
 	github.com/grpc-ecosystem/grpc-gateway v1.16.0 // indirect
 	github.com/huandu/xstrings v1.3.2 // indirect
 	github.com/imdario/mergo v0.3.12 // indirect
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
 	github.com/jackc/chunkreader/v2 v2.0.1 // indirect
 	github.com/jackc/pgconn v1.10.1 // indirect
 	github.com/jackc/pgio v1.0.0 // indirect
@@ -101,7 +105,7 @@ require (
 	github.com/prometheus/common v0.32.1 // indirect
 	github.com/prometheus/procfs v0.7.3 // indirect
 	github.com/rs/xid v1.2.1 // indirect
-	github.com/russross/blackfriday/v2 v2.0.1 // indirect
+	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/shopspring/decimal v1.2.0 // indirect
 	github.com/shurcooL/sanitized_anchor_name v1.0.0 // indirect
 	github.com/sirupsen/logrus v1.8.1 // indirect