package cli
import (
"fmt"
"io/ioutil"
"sort"
"strings"
)
// Command is a subcommand for a cli.App.
type Command struct {
// The name of the command
Name string
// short name of the command. Typically one character (deprecated, use `Aliases`)
ShortName string
// A list of aliases for the command
Aliases []string
// A short description of the usage of this command
Usage string
// Custom text to show on USAGE section of help
UsageText string
// A longer explanation of how the command works
Description string
// A short description of the arguments of this command
ArgsUsage string
// The category the command is part of
Category string
// The function to call when checking for bash command completions
BashComplete BashCompleteFunc
// An action to execute before any sub-subcommands are run, but after the context is ready
// If a non-nil error is returned, no sub-subcommands are run
Before BeforeFunc
// An action to execute after any subcommands are run, but after the subcommand has finished
// It is run even if Action() panics
After AfterFunc
// The function to call when this command is invoked
Action interface{}
// TODO: replace `Action: interface{}` with `Action: ActionFunc` once some kind
// of deprecation period has passed, maybe?
// Execute this function if a usage error occurs.
OnUsageError OnUsageErrorFunc
// List of child commands
Subcommands Commands
// List of flags to parse
Flags []Flag
// Treat all flags as normal arguments if true
SkipFlagParsing bool
// Skip argument reordering which attempts to move flags before arguments,
// but only works if all flags appear after all arguments. This behavior was
// removed n version 2 since it only works under specific conditions so we
// backport here by exposing it as an option for compatibility.
SkipArgReorder bool
// Boolean to hide built-in help command
HideHelp bool
// Boolean to hide this command from help or completion
Hidden bool
// Full name of command for help, defaults to full command name, including parent commands.
HelpName string
commandNamePath []string
// CustomHelpTemplate the text template for the command help topic.
// cli.go uses text/template to render templates. You can
// render custom help text by setting this variable.
CustomHelpTemplate string
}
type CommandsByName []Command
func (c CommandsByName) Len() int {
return len(c)
}
func (c CommandsByName) Less(i, j int) bool {
return c[i].Name < c[j].Name
}
func (c CommandsByName) Swap(i, j int) {
c[i], c[j] = c[j], c[i]
}
// FullName returns the full name of the command.
// For subcommands this ensures that parent commands are part of the command path
func (c Command) FullName() string {
if c.commandNamePath == nil {
return c.Name
}
return strings.Join(c.commandNamePath, " ")
}
// Commands is a slice of Command
type Commands []Command
// Run invokes the command given the context, parses ctx.Args() to generate command-specific flags
func (c Command) Run(ctx *Context) (err error) {
if len(c.Subcommands) > 0 {
return c.startApp(ctx)
}
if !c.HideHelp && (HelpFlag != BoolFlag{}) {
// append help to flags
c.Flags = append(
c.Flags,
HelpFlag,
)
}
set, err := flagSet(c.Name, c.Flags)
if err != nil {
return err
}
set.SetOutput(ioutil.Discard)
if c.SkipFlagParsing {
err = set.Parse(append([]string{"--"}, ctx.Args().Tail()...))
} else if !c.SkipArgReorder {
firstFlagIndex := -1
terminatorIndex := -1
for index, arg := range ctx.Args() {
if arg == "--" {
terminatorIndex = index
break
} else if arg == "-" {
// Do nothing. A dash alone is not really a flag.
continue
} else if strings.HasPrefix(arg, "-") && firstFlagIndex == -1 {
firstFlagIndex = index
}
}
if firstFlagIndex > -1 {
args := ctx.Args()
regularArgs := make([]string, len(args[1:firstFlagIndex]))
copy(regularArgs, args[1:firstFlagIndex])
var flagArgs []string
if terminatorIndex > -1 {
flagArgs = args[firstFlagIndex:terminatorIndex]
regularArgs = append(regularArgs, args[terminatorIndex:]...)
} else {
flagArgs = args[firstFlagIndex:]
}
err = set.Parse(append(flagArgs, regularArgs...))
} else {
err = set.Parse(ctx.Args().Tail())
}
} else {
err = set.Parse(ctx.Args().Tail())
}
nerr := normalizeFlags(c.Flags, set)
if nerr != nil {
fmt.Fprintln(ctx.App.Writer, nerr)
fmt.Fprintln(ctx.App.Writer)
ShowCommandHelp(ctx, c.Name)
return nerr
}
context := NewContext(ctx.App, set, ctx)
context.Command = c
if checkCommandCompletions(context, c.Name) {
return nil
}
if err != nil {
if c.OnUsageError != nil {
err := c.OnUsageError(context, err, false)
HandleExitCoder(err)
return err
}
fmt.Fprintln(context.App.Writer, "Incorrect Usage:", err.Error())
fmt.Fprintln(context.App.Writer)
ShowCommandHelp(context, c.Name)
return err
}
if checkCommandHelp(context, c.Name) {
return nil
}
if c.After != nil {
defer func() {
afterErr := c.After(context)
if afterErr != nil {
HandleExitCoder(err)
if err != nil {
err = NewMultiError(err, afterErr)
} else {
err = afterErr
}
}
}()
}
if c.Before != nil {
err = c.Before(context)
if err != nil {
ShowCommandHelp(context, c.Name)
HandleExitCoder(err)
return err
}
}
if c.Action == nil {
c.Action = helpSubcommand.Action
}
err = HandleAction(c.Action, context)
if err != nil {
HandleExitCoder(err)
}
return err
}
// Names returns the names including short names and aliases.
func (c Command) Names() []string {
names := []string{c.Name}
if c.ShortName != "" {
names = append(names, c.ShortName)
}
return append(names, c.Aliases...)
}
// HasName returns true if Command.Name or Command.ShortName matches given name
func (c Command) HasName(name string) bool {
for _, n := range c.Names() {
if n == name {
return true
}
}
return false
}
func (c Command) startApp(ctx *Context) error {
app := NewApp()
app.Metadata = ctx.App.Metadata
// set the name and usage
app.Name = fmt.Sprintf("%s %s", ctx.App.Name, c.Name)
if c.HelpName == "" {
app.HelpName = c.HelpName
} else {
app.HelpName = app.Name
}
app.Usage = c.Usage
app.Description = c.Description
app.ArgsUsage = c.ArgsUsage
// set CommandNotFound
app.CommandNotFound = ctx.App.CommandNotFound
app.CustomAppHelpTemplate = c.CustomHelpTemplate
// set the flags and commands
app.Commands = c.Subcommands
app.Flags = c.Flags
app.HideHelp = c.HideHelp
app.Version = ctx.App.Version
app.HideVersion = ctx.App.HideVersion
app.Compiled = ctx.App.Compiled
app.Author = ctx.App.Author
app.Email = ctx.App.Email
app.Writer = ctx.App.Writer
app.ErrWriter = ctx.App.ErrWriter
app.categories = CommandCategories{}
for _, command := range c.Subcommands {
app.categories = app.categories.AddCommand(command.Category, command)
}
sort.Sort(app.categories)
// bash completion
app.EnableBashCompletion = ctx.App.EnableBashCompletion
if c.BashComplete != nil {
app.BashComplete = c.BashComplete
}
// set the actions
app.Before = c.Before
app.After = c.After
if c.Action != nil {
app.Action = c.Action
} else {
app.Action = helpSubcommand.Action
}
app.OnUsageError = c.OnUsageError
for index, cc := range app.Commands {
app.Commands[index].commandNamePath = []string{c.Name, cc.Name}
}
return app.RunAsSubcommand(ctx)
}
// VisibleFlags returns a slice of the Flags with Hidden=false
func (c Command) VisibleFlags() []Flag {
return visibleFlags(c.Flags)
}
