v1.0.0

main/commands/base/command.go

@@ -0,0 +1,122 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package base defines shared basic pieces of the commands,
+// in particular logging and the Command structure.
+package base
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"strings"
+	"sync"
+)
+
+// A Command is an implementation of a xray command
+// like xray run or xray version.
+type Command struct {
+	// Run runs the command.
+	// The args are the arguments after the command name.
+	Run func(cmd *Command, args []string)
+
+	// UsageLine is the one-line usage message.
+	// The words between "go" and the first flag or argument in the line are taken to be the command name.
+	UsageLine string
+
+	// Short is the short description shown in the 'go help' output.
+	Short string
+
+	// Long is the long message shown in the 'go help <this-command>' output.
+	Long string
+
+	// Flag is a set of flags specific to this command.
+	Flag flag.FlagSet
+
+	// CustomFlags indicates that the command will do its own
+	// flag parsing.
+	CustomFlags bool
+
+	// Commands lists the available commands and help topics.
+	// The order here is the order in which they are printed by 'go help'.
+	// Note that subcommands are in general best avoided.
+	Commands []*Command
+}
+
+// LongName returns the command's long name: all the words in the usage line between "go" and a flag or argument,
+func (c *Command) LongName() string {
+	name := c.UsageLine
+	if i := strings.Index(name, " ["); i >= 0 {
+		name = name[:i]
+	}
+	if name == CommandEnv.Exec {
+		return ""
+	}
+	return strings.TrimPrefix(name, CommandEnv.Exec+" ")
+}
+
+// Name returns the command's short name: the last word in the usage line before a flag or argument.
+func (c *Command) Name() string {
+	name := c.LongName()
+	if i := strings.LastIndex(name, " "); i >= 0 {
+		name = name[i+1:]
+	}
+	return name
+}
+
+// Usage prints usage of the Command
+func (c *Command) Usage() {
+	fmt.Fprintf(os.Stderr, "usage: %s\n", c.UsageLine)
+	fmt.Fprintf(os.Stderr, "Run 'xray help %s' for details.\n", c.LongName())
+	SetExitStatus(2)
+	Exit()
+}
+
+// Runnable reports whether the command can be run; otherwise
+// it is a documentation pseudo-command such as importpath.
+func (c *Command) Runnable() bool {
+	return c.Run != nil
+}
+
+// Exit exits with code set with SetExitStatus()
+func Exit() {
+	os.Exit(exitStatus)
+}
+
+// Fatalf logs error and exit with code 1
+func Fatalf(format string, args ...interface{}) {
+	Errorf(format, args...)
+	Exit()
+}
+
+// Errorf logs error and set exit status to 1, but not exit
+func Errorf(format string, args ...interface{}) {
+	fmt.Fprintf(os.Stderr, format, args...)
+	fmt.Fprintln(os.Stderr)
+	SetExitStatus(1)
+}
+
+// ExitIfErrors exits if current status is not zero
+func ExitIfErrors() {
+	if exitStatus != 0 {
+		Exit()
+	}
+}
+
+var exitStatus = 0
+var exitMu sync.Mutex
+
+// SetExitStatus set exit status code
+func SetExitStatus(n int) {
+	exitMu.Lock()
+	if exitStatus < n {
+		exitStatus = n
+	}
+	exitMu.Unlock()
+}
+
+// GetExitStatus get exit status code
+func GetExitStatus() int {
+	return exitStatus
+}

main/commands/base/env.go

@@ -0,0 +1,23 @@
+package base
+
+import (
+	"os"
+	"path"
+)
+
+// CommandEnvHolder is a struct holds the environment info of commands
+type CommandEnvHolder struct {
+	Exec string
+}
+
+// CommandEnv holds the environment info of commands
+var CommandEnv CommandEnvHolder
+
+func init() {
+	exec, err := os.Executable()
+	if err != nil {
+		return
+	}
+	CommandEnv.Exec = path.Base(exec)
+	CommandEnv.Exec = "xray"
+}

main/commands/base/execute.go

@@ -0,0 +1,88 @@
+package base
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"sort"
+	"strings"
+)
+
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// copied from "github.com/golang/go/main.go"
+
+// Execute excute the commands
+func Execute() {
+	buildCommandsText(RootCommand)
+	flag.Parse()
+	args := flag.Args()
+	if len(args) < 1 {
+		PrintUsage(os.Stderr, RootCommand)
+		return
+	}
+	cmdName := args[0] // for error messages
+	if args[0] == "help" {
+		Help(os.Stdout, args[1:])
+		return
+	}
+
+BigCmdLoop:
+	for bigCmd := RootCommand; ; {
+		for _, cmd := range bigCmd.Commands {
+			if cmd.Name() != args[0] {
+				continue
+			}
+			if len(cmd.Commands) > 0 {
+				// test sub commands
+				bigCmd = cmd
+				args = args[1:]
+				if len(args) == 0 {
+					PrintUsage(os.Stderr, bigCmd)
+					SetExitStatus(2)
+					Exit()
+				}
+				if args[0] == "help" {
+					// Accept 'go mod help' and 'go mod help foo' for 'go help mod' and 'go help mod foo'.
+					Help(os.Stdout, append(strings.Split(cmdName, " "), args[1:]...))
+					return
+				}
+				cmdName += " " + args[0]
+				continue BigCmdLoop
+			}
+			if !cmd.Runnable() {
+				continue
+			}
+			cmd.Flag.Usage = func() { cmd.Usage() }
+			if cmd.CustomFlags {
+				args = args[1:]
+			} else {
+				cmd.Flag.Parse(args[1:])
+				args = cmd.Flag.Args()
+			}
+
+			cmd.Run(cmd, args)
+			Exit()
+			return
+		}
+		helpArg := ""
+		if i := strings.LastIndex(cmdName, " "); i >= 0 {
+			helpArg = " " + cmdName[:i]
+		}
+		fmt.Fprintf(os.Stderr, "%s %s: unknown command\nRun '%s help%s' for usage.\n", CommandEnv.Exec, cmdName, CommandEnv.Exec, helpArg)
+		SetExitStatus(2)
+		Exit()
+	}
+}
+
+// Sort sorts the commands
+func Sort() {
+	sort.Slice(RootCommand.Commands, func(i, j int) bool {
+		return SortLessFunc(RootCommand.Commands[i], RootCommand.Commands[j])
+	})
+}
+
+// SortLessFunc used for sort commands list, can be override from outside
+var SortLessFunc = func(i, j *Command) bool {
+	return i.Name() < j.Name()
+}

main/commands/base/help.go

@@ -0,0 +1,157 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package base
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+	"text/template"
+	"unicode"
+	"unicode/utf8"
+)
+
+// Help implements the 'help' command.
+func Help(w io.Writer, args []string) {
+	cmd := RootCommand
+Args:
+	for i, arg := range args {
+		for _, sub := range cmd.Commands {
+			if sub.Name() == arg {
+				cmd = sub
+				continue Args
+			}
+		}
+
+		// helpSuccess is the help command using as many args as possible that would succeed.
+		helpSuccess := CommandEnv.Exec + " help"
+		if i > 0 {
+			helpSuccess += " " + strings.Join(args[:i], " ")
+		}
+		fmt.Fprintf(os.Stderr, "%s help %s: unknown help topic. Run '%s'.\n", CommandEnv.Exec, strings.Join(args, " "), helpSuccess)
+		SetExitStatus(2) // failed at 'xray help cmd'
+		Exit()
+	}
+
+	if len(cmd.Commands) > 0 {
+		PrintUsage(os.Stdout, cmd)
+	} else {
+		tmpl(os.Stdout, helpTemplate, makeTmplData(cmd))
+	}
+}
+
+var usageTemplate = `{{.Long | trim}}
+
+Usage:
+
+	{{.Exec}} <command> [arguments]
+
+The commands are:
+{{range .Commands}}{{if and (ne .Short "") (or (.Runnable) .Commands)}}
+	{{.Name | printf "%-12s"}} {{.Short}}{{end}}{{end}}
+
+Use "{{.Exec}} help{{with .LongName}} {{.}}{{end}} <command>" for more information about a command.
+`
+
+// APPEND FOLLOWING TO 'usageTemplate' IF YOU WANT DOC,
+// A DOC TOPIC IS JUST A COMMAND NOT RUNNABLE:
+//
+// {{if eq (.UsageLine) (.Exec)}}
+// Additional help topics:
+// {{range .Commands}}{{if and (not .Runnable) (not .Commands)}}
+// 	{{.Name | printf "%-15s"}} {{.Short}}{{end}}{{end}}
+//
+// Use "{{.Exec}} help{{with .LongName}} {{.}}{{end}} <topic>" for more information about that topic.
+// {{end}}
+
+var helpTemplate = `{{if .Runnable}}usage: {{.UsageLine}}
+
+{{end}}{{.Long | trim}}
+`
+
+// An errWriter wraps a writer, recording whether a write error occurred.
+type errWriter struct {
+	w   io.Writer
+	err error
+}
+
+func (w *errWriter) Write(b []byte) (int, error) {
+	n, err := w.w.Write(b)
+	if err != nil {
+		w.err = err
+	}
+	return n, err
+}
+
+// tmpl executes the given template text on data, writing the result to w.
+func tmpl(w io.Writer, text string, data interface{}) {
+	t := template.New("top")
+	t.Funcs(template.FuncMap{"trim": strings.TrimSpace, "capitalize": capitalize})
+	template.Must(t.Parse(text))
+	ew := &errWriter{w: w}
+	err := t.Execute(ew, data)
+	if ew.err != nil {
+		// I/O error writing. Ignore write on closed pipe.
+		if strings.Contains(ew.err.Error(), "pipe") {
+			SetExitStatus(1)
+			Exit()
+		}
+		Fatalf("writing output: %v", ew.err)
+	}
+	if err != nil {
+		panic(err)
+	}
+}
+
+func capitalize(s string) string {
+	if s == "" {
+		return s
+	}
+	r, n := utf8.DecodeRuneInString(s)
+	return string(unicode.ToTitle(r)) + s[n:]
+}
+
+// PrintUsage prints usage of cmd to w
+func PrintUsage(w io.Writer, cmd *Command) {
+	bw := bufio.NewWriter(w)
+	tmpl(bw, usageTemplate, makeTmplData(cmd))
+	bw.Flush()
+}
+
+// buildCommandsText build text of command and its children as template
+func buildCommandsText(cmd *Command) {
+	buildCommandText(cmd)
+	for _, cmd := range cmd.Commands {
+		buildCommandsText(cmd)
+	}
+}
+
+// buildCommandText build command text as template
+func buildCommandText(cmd *Command) {
+	cmd.UsageLine = buildText(cmd.UsageLine, makeTmplData(cmd))
+	cmd.Short = buildText(cmd.Short, makeTmplData(cmd))
+	cmd.Long = buildText(cmd.Long, makeTmplData(cmd))
+}
+
+func buildText(text string, data interface{}) string {
+	buf := bytes.NewBuffer([]byte{})
+	tmpl(buf, text, data)
+	return buf.String()
+}
+
+type tmplData struct {
+	*Command
+	*CommandEnvHolder
+}
+
+func makeTmplData(cmd *Command) tmplData {
+	return tmplData{
+		Command:          cmd,
+		CommandEnvHolder: &CommandEnv,
+	}
+}

main/commands/base/root.go

@@ -0,0 +1,16 @@
+package base
+
+// RootCommand is the root command of all commands
+var RootCommand *Command
+
+func init() {
+	RootCommand = &Command{
+		UsageLine: CommandEnv.Exec,
+		Long:      "The root command",
+	}
+}
+
+// RegisterCommand register a command to RootCommand
+func RegisterCommand(cmd *Command) {
+	RootCommand.Commands = append(RootCommand.Commands, cmd)
+}