cobra/command.go
Thomas Cyron 7b2c5ac9fc Create new buffer if not present yet (#549)
Fixes a nil dereference when TraverseChildren is used
with multiple subcommands.
2017-10-12 20:25:33 +02:00

1410 lines
39 KiB
Go

// Copyright © 2013 Steve Francia <spf@spf13.com>.
//
// 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 cobra is a commander providing a simple interface to create powerful modern CLI interfaces.
// In addition to providing an interface, Cobra simultaneously provides a controller to organize your application code.
package cobra
import (
"bytes"
"fmt"
"io"
"os"
"path/filepath"
"sort"
"strings"
flag "github.com/spf13/pflag"
)
// Command is just that, a command for your application.
// E.g. 'go run ...' - 'run' is the command. Cobra requires
// you to define the usage and description as part of your command
// definition to ensure usability.
type Command struct {
// Use is the one-line usage message.
Use string
// Aliases is an array of aliases that can be used instead of the first word in Use.
Aliases []string
// SuggestFor is an array of command names for which this command will be suggested -
// similar to aliases but only suggests.
SuggestFor []string
// Short is the short description shown in the 'help' output.
Short string
// Long is the long message shown in the 'help <this-command>' output.
Long string
// Example is examples of how to use the command.
Example string
// ValidArgs is list of all valid non-flag arguments that are accepted in bash completions
ValidArgs []string
// Expected arguments
Args PositionalArgs
// ArgAliases is List of aliases for ValidArgs.
// These are not suggested to the user in the bash completion,
// but accepted if entered manually.
ArgAliases []string
// BashCompletionFunction is custom functions used by the bash autocompletion generator.
BashCompletionFunction string
// Deprecated defines, if this command is deprecated and should print this string when used.
Deprecated string
// Hidden defines, if this command is hidden and should NOT show up in the list of available commands.
Hidden bool
// Annotations are key/value pairs that can be used by applications to identify or
// group commands.
Annotations map[string]string
// The *Run functions are executed in the following order:
// * PersistentPreRun()
// * PreRun()
// * Run()
// * PostRun()
// * PersistentPostRun()
// All functions get the same args, the arguments after the command name.
//
// PersistentPreRun: children of this command will inherit and execute.
PersistentPreRun func(cmd *Command, args []string)
// PersistentPreRunE: PersistentPreRun but returns an error.
PersistentPreRunE func(cmd *Command, args []string) error
// PreRun: children of this command will not inherit.
PreRun func(cmd *Command, args []string)
// PreRunE: PreRun but returns an error.
PreRunE func(cmd *Command, args []string) error
// Run: Typically the actual work function. Most commands will only implement this.
Run func(cmd *Command, args []string)
// RunE: Run but returns an error.
RunE func(cmd *Command, args []string) error
// PostRun: run after the Run command.
PostRun func(cmd *Command, args []string)
// PostRunE: PostRun but returns an error.
PostRunE func(cmd *Command, args []string) error
// PersistentPostRun: children of this command will inherit and execute after PostRun.
PersistentPostRun func(cmd *Command, args []string)
// PersistentPostRunE: PersistentPostRun but returns an error.
PersistentPostRunE func(cmd *Command, args []string) error
// SilenceErrors is an option to quiet errors down stream.
SilenceErrors bool
// SilenceUsage is an option to silence usage when an error occurs.
SilenceUsage bool
// DisableFlagParsing disables the flag parsing.
// If this is true all flags will be passed to the command as arguments.
DisableFlagParsing bool
// DisableAutoGenTag defines, if gen tag ("Auto generated by spf13/cobra...")
// will be printed by generating docs for this command.
DisableAutoGenTag bool
// DisableSuggestions disables the suggestions based on Levenshtein distance
// that go along with 'unknown command' messages.
DisableSuggestions bool
// SuggestionsMinimumDistance defines minimum levenshtein distance to display suggestions.
// Must be > 0.
SuggestionsMinimumDistance int
// TraverseChildren parses flags on all parents before executing child command.
TraverseChildren bool
// commands is the list of commands supported by this program.
commands []*Command
// parent is a parent command for this command.
parent *Command
// Max lengths of commands' string lengths for use in padding.
commandsMaxUseLen int
commandsMaxCommandPathLen int
commandsMaxNameLen int
// commandsAreSorted defines, if command slice are sorted or not.
commandsAreSorted bool
// args is actual args parsed from flags.
args []string
// flagErrorBuf contains all error messages from pflag.
flagErrorBuf *bytes.Buffer
// flags is full set of flags.
flags *flag.FlagSet
// pflags contains persistent flags.
pflags *flag.FlagSet
// lflags contains local flags.
lflags *flag.FlagSet
// iflags contains inherited flags.
iflags *flag.FlagSet
// parentsPflags is all persistent flags of cmd's parents.
parentsPflags *flag.FlagSet
// globNormFunc is the global normalization function
// that we can use on every pflag set and children commands
globNormFunc func(f *flag.FlagSet, name string) flag.NormalizedName
// output is an output writer defined by user.
output io.Writer
// usageFunc is usage func defined by user.
usageFunc func(*Command) error
// usageTemplate is usage template defined by user.
usageTemplate string
// flagErrorFunc is func defined by user and it's called when the parsing of
// flags returns an error.
flagErrorFunc func(*Command, error) error
// helpTemplate is help template defined by user.
helpTemplate string
// helpFunc is help func defined by user.
helpFunc func(*Command, []string)
// helpCommand is command with usage 'help'. If it's not defined by user,
// cobra uses default help command.
helpCommand *Command
}
// SetArgs sets arguments for the command. It is set to os.Args[1:] by default, if desired, can be overridden
// particularly useful when testing.
func (c *Command) SetArgs(a []string) {
c.args = a
}
// SetOutput sets the destination for usage and error messages.
// If output is nil, os.Stderr is used.
func (c *Command) SetOutput(output io.Writer) {
c.output = output
}
// SetUsageFunc sets usage function. Usage can be defined by application.
func (c *Command) SetUsageFunc(f func(*Command) error) {
c.usageFunc = f
}
// SetUsageTemplate sets usage template. Can be defined by Application.
func (c *Command) SetUsageTemplate(s string) {
c.usageTemplate = s
}
// SetFlagErrorFunc sets a function to generate an error when flag parsing
// fails.
func (c *Command) SetFlagErrorFunc(f func(*Command, error) error) {
c.flagErrorFunc = f
}
// SetHelpFunc sets help function. Can be defined by Application.
func (c *Command) SetHelpFunc(f func(*Command, []string)) {
c.helpFunc = f
}
// SetHelpCommand sets help command.
func (c *Command) SetHelpCommand(cmd *Command) {
c.helpCommand = cmd
}
// SetHelpTemplate sets help template to be used. Application can use it to set custom template.
func (c *Command) SetHelpTemplate(s string) {
c.helpTemplate = s
}
// SetGlobalNormalizationFunc sets a normalization function to all flag sets and also to child commands.
// The user should not have a cyclic dependency on commands.
func (c *Command) SetGlobalNormalizationFunc(n func(f *flag.FlagSet, name string) flag.NormalizedName) {
c.Flags().SetNormalizeFunc(n)
c.PersistentFlags().SetNormalizeFunc(n)
c.globNormFunc = n
for _, command := range c.commands {
command.SetGlobalNormalizationFunc(n)
}
}
// OutOrStdout returns output to stdout.
func (c *Command) OutOrStdout() io.Writer {
return c.getOut(os.Stdout)
}
// OutOrStderr returns output to stderr
func (c *Command) OutOrStderr() io.Writer {
return c.getOut(os.Stderr)
}
func (c *Command) getOut(def io.Writer) io.Writer {
if c.output != nil {
return c.output
}
if c.HasParent() {
return c.parent.getOut(def)
}
return def
}
// UsageFunc returns either the function set by SetUsageFunc for this command
// or a parent, or it returns a default usage function.
func (c *Command) UsageFunc() (f func(*Command) error) {
if c.usageFunc != nil {
return c.usageFunc
}
if c.HasParent() {
return c.Parent().UsageFunc()
}
return func(c *Command) error {
c.mergePersistentFlags()
err := tmpl(c.OutOrStderr(), c.UsageTemplate(), c)
if err != nil {
c.Println(err)
}
return err
}
}
// Usage puts out the usage for the command.
// Used when a user provides invalid input.
// Can be defined by user by overriding UsageFunc.
func (c *Command) Usage() error {
return c.UsageFunc()(c)
}
// HelpFunc returns either the function set by SetHelpFunc for this command
// or a parent, or it returns a function with default help behavior.
func (c *Command) HelpFunc() func(*Command, []string) {
if c.helpFunc != nil {
return c.helpFunc
}
if c.HasParent() {
return c.Parent().HelpFunc()
}
return func(c *Command, a []string) {
c.mergePersistentFlags()
err := tmpl(c.OutOrStdout(), c.HelpTemplate(), c)
if err != nil {
c.Println(err)
}
}
}
// Help puts out the help for the command.
// Used when a user calls help [command].
// Can be defined by user by overriding HelpFunc.
func (c *Command) Help() error {
c.HelpFunc()(c, []string{})
return nil
}
// UsageString return usage string.
func (c *Command) UsageString() string {
tmpOutput := c.output
bb := new(bytes.Buffer)
c.SetOutput(bb)
c.Usage()
c.output = tmpOutput
return bb.String()
}
// FlagErrorFunc returns either the function set by SetFlagErrorFunc for this
// command or a parent, or it returns a function which returns the original
// error.
func (c *Command) FlagErrorFunc() (f func(*Command, error) error) {
if c.flagErrorFunc != nil {
return c.flagErrorFunc
}
if c.HasParent() {
return c.parent.FlagErrorFunc()
}
return func(c *Command, err error) error {
return err
}
}
var minUsagePadding = 25
// UsagePadding return padding for the usage.
func (c *Command) UsagePadding() int {
if c.parent == nil || minUsagePadding > c.parent.commandsMaxUseLen {
return minUsagePadding
}
return c.parent.commandsMaxUseLen
}
var minCommandPathPadding = 11
// CommandPathPadding return padding for the command path.
func (c *Command) CommandPathPadding() int {
if c.parent == nil || minCommandPathPadding > c.parent.commandsMaxCommandPathLen {
return minCommandPathPadding
}
return c.parent.commandsMaxCommandPathLen
}
var minNamePadding = 11
// NamePadding returns padding for the name.
func (c *Command) NamePadding() int {
if c.parent == nil || minNamePadding > c.parent.commandsMaxNameLen {
return minNamePadding
}
return c.parent.commandsMaxNameLen
}
// UsageTemplate returns usage template for the command.
func (c *Command) UsageTemplate() string {
if c.usageTemplate != "" {
return c.usageTemplate
}
if c.HasParent() {
return c.parent.UsageTemplate()
}
return `Usage:{{if .Runnable}}
{{.UseLine}}{{end}}{{if .HasAvailableSubCommands}}
{{.CommandPath}} [command]{{end}}{{if gt (len .Aliases) 0}}
Aliases:
{{.NameAndAliases}}{{end}}{{if .HasExample}}
Examples:
{{.Example}}{{end}}{{if .HasAvailableSubCommands}}
Available Commands:{{range .Commands}}{{if (or .IsAvailableCommand (eq .Name "help"))}}
{{rpad .Name .NamePadding }} {{.Short}}{{end}}{{end}}{{end}}{{if .HasAvailableLocalFlags}}
Flags:
{{.LocalFlags.FlagUsages | trimTrailingWhitespaces}}{{end}}{{if .HasAvailableInheritedFlags}}
Global Flags:
{{.InheritedFlags.FlagUsages | trimTrailingWhitespaces}}{{end}}{{if .HasHelpSubCommands}}
Additional help topics:{{range .Commands}}{{if .IsAdditionalHelpTopicCommand}}
{{rpad .CommandPath .CommandPathPadding}} {{.Short}}{{end}}{{end}}{{end}}{{if .HasAvailableSubCommands}}
Use "{{.CommandPath}} [command] --help" for more information about a command.{{end}}
`
}
// HelpTemplate return help template for the command.
func (c *Command) HelpTemplate() string {
if c.helpTemplate != "" {
return c.helpTemplate
}
if c.HasParent() {
return c.parent.HelpTemplate()
}
return `{{with (or .Long .Short)}}{{. | trimTrailingWhitespaces}}
{{end}}{{if or .Runnable .HasSubCommands}}{{.UsageString}}{{end}}`
}
func hasNoOptDefVal(name string, fs *flag.FlagSet) bool {
flag := fs.Lookup(name)
if flag == nil {
return false
}
return flag.NoOptDefVal != ""
}
func shortHasNoOptDefVal(name string, fs *flag.FlagSet) bool {
if len(name) == 0 {
return false
}
flag := fs.ShorthandLookup(name[:1])
if flag == nil {
return false
}
return flag.NoOptDefVal != ""
}
func stripFlags(args []string, c *Command) []string {
if len(args) == 0 {
return args
}
c.mergePersistentFlags()
commands := []string{}
flags := c.Flags()
Loop:
for len(args) > 0 {
s := args[0]
args = args[1:]
switch {
case strings.HasPrefix(s, "--") && !strings.Contains(s, "=") && !hasNoOptDefVal(s[2:], flags):
// If '--flag arg' then
// delete arg from args.
fallthrough // (do the same as below)
case strings.HasPrefix(s, "-") && !strings.Contains(s, "=") && len(s) == 2 && !shortHasNoOptDefVal(s[1:], flags):
// If '-f arg' then
// delete 'arg' from args or break the loop if len(args) <= 1.
if len(args) <= 1 {
break Loop
} else {
args = args[1:]
continue
}
case s != "" && !strings.HasPrefix(s, "-"):
commands = append(commands, s)
}
}
return commands
}
// argsMinusFirstX removes only the first x from args. Otherwise, commands that look like
// openshift admin policy add-role-to-user admin my-user, lose the admin argument (arg[4]).
func argsMinusFirstX(args []string, x string) []string {
for i, y := range args {
if x == y {
ret := []string{}
ret = append(ret, args[:i]...)
ret = append(ret, args[i+1:]...)
return ret
}
}
return args
}
func isFlagArg(arg string) bool {
return ((len(arg) >= 3 && arg[1] == '-') ||
(len(arg) >= 2 && arg[0] == '-' && arg[1] != '-'))
}
// Find the target command given the args and command tree
// Meant to be run on the highest node. Only searches down.
func (c *Command) Find(args []string) (*Command, []string, error) {
var innerfind func(*Command, []string) (*Command, []string)
innerfind = func(c *Command, innerArgs []string) (*Command, []string) {
argsWOflags := stripFlags(innerArgs, c)
if len(argsWOflags) == 0 {
return c, innerArgs
}
nextSubCmd := argsWOflags[0]
cmd := c.findNext(nextSubCmd)
if cmd != nil {
return innerfind(cmd, argsMinusFirstX(innerArgs, nextSubCmd))
}
return c, innerArgs
}
commandFound, a := innerfind(c, args)
if commandFound.Args == nil {
return commandFound, a, legacyArgs(commandFound, stripFlags(a, commandFound))
}
return commandFound, a, nil
}
func (c *Command) findSuggestions(arg string) string {
if c.DisableSuggestions {
return ""
}
if c.SuggestionsMinimumDistance <= 0 {
c.SuggestionsMinimumDistance = 2
}
suggestionsString := ""
if suggestions := c.SuggestionsFor(arg); len(suggestions) > 0 {
suggestionsString += "\n\nDid you mean this?\n"
for _, s := range suggestions {
suggestionsString += fmt.Sprintf("\t%v\n", s)
}
}
return suggestionsString
}
func (c *Command) findNext(next string) *Command {
matches := make([]*Command, 0)
for _, cmd := range c.commands {
if cmd.Name() == next || cmd.HasAlias(next) {
return cmd
}
if EnablePrefixMatching && cmd.hasNameOrAliasPrefix(next) {
matches = append(matches, cmd)
}
}
if len(matches) == 1 {
return matches[0]
}
return nil
}
// Traverse the command tree to find the command, and parse args for
// each parent.
func (c *Command) Traverse(args []string) (*Command, []string, error) {
flags := []string{}
inFlag := false
for i, arg := range args {
switch {
// A long flag with a space separated value
case strings.HasPrefix(arg, "--") && !strings.Contains(arg, "="):
// TODO: this isn't quite right, we should really check ahead for 'true' or 'false'
inFlag = !hasNoOptDefVal(arg[2:], c.Flags())
flags = append(flags, arg)
continue
// A short flag with a space separated value
case strings.HasPrefix(arg, "-") && !strings.Contains(arg, "=") && len(arg) == 2 && !shortHasNoOptDefVal(arg[1:], c.Flags()):
inFlag = true
flags = append(flags, arg)
continue
// The value for a flag
case inFlag:
inFlag = false
flags = append(flags, arg)
continue
// A flag without a value, or with an `=` separated value
case isFlagArg(arg):
flags = append(flags, arg)
continue
}
cmd := c.findNext(arg)
if cmd == nil {
return c, args, nil
}
if err := c.ParseFlags(flags); err != nil {
return nil, args, err
}
return cmd.Traverse(args[i+1:])
}
return c, args, nil
}
// SuggestionsFor provides suggestions for the typedName.
func (c *Command) SuggestionsFor(typedName string) []string {
suggestions := []string{}
for _, cmd := range c.commands {
if cmd.IsAvailableCommand() {
levenshteinDistance := ld(typedName, cmd.Name(), true)
suggestByLevenshtein := levenshteinDistance <= c.SuggestionsMinimumDistance
suggestByPrefix := strings.HasPrefix(strings.ToLower(cmd.Name()), strings.ToLower(typedName))
if suggestByLevenshtein || suggestByPrefix {
suggestions = append(suggestions, cmd.Name())
}
for _, explicitSuggestion := range cmd.SuggestFor {
if strings.EqualFold(typedName, explicitSuggestion) {
suggestions = append(suggestions, cmd.Name())
}
}
}
}
return suggestions
}
// VisitParents visits all parents of the command and invokes fn on each parent.
func (c *Command) VisitParents(fn func(*Command)) {
if c.HasParent() {
fn(c.Parent())
c.Parent().VisitParents(fn)
}
}
// Root finds root command.
func (c *Command) Root() *Command {
if c.HasParent() {
return c.Parent().Root()
}
return c
}
// ArgsLenAtDash will return the length of f.Args at the moment when a -- was
// found during arg parsing. This allows your program to know which args were
// before the -- and which came after. (Description from
// https://godoc.org/github.com/spf13/pflag#FlagSet.ArgsLenAtDash).
func (c *Command) ArgsLenAtDash() int {
return c.Flags().ArgsLenAtDash()
}
func (c *Command) execute(a []string) (err error) {
if c == nil {
return fmt.Errorf("Called Execute() on a nil Command")
}
if len(c.Deprecated) > 0 {
c.Printf("Command %q is deprecated, %s\n", c.Name(), c.Deprecated)
}
// initialize help flag as the last point possible to allow for user
// overriding
c.InitDefaultHelpFlag()
err = c.ParseFlags(a)
if err != nil {
return c.FlagErrorFunc()(c, err)
}
// If help is called, regardless of other flags, return we want help.
// Also say we need help if the command isn't runnable.
helpVal, err := c.Flags().GetBool("help")
if err != nil {
// should be impossible to get here as we always declare a help
// flag in InitDefaultHelpFlag()
c.Println("\"help\" flag declared as non-bool. Please correct your code")
return err
}
if helpVal || !c.Runnable() {
return flag.ErrHelp
}
c.preRun()
argWoFlags := c.Flags().Args()
if c.DisableFlagParsing {
argWoFlags = a
}
if err := c.ValidateArgs(argWoFlags); err != nil {
return err
}
for p := c; p != nil; p = p.Parent() {
if p.PersistentPreRunE != nil {
if err := p.PersistentPreRunE(c, argWoFlags); err != nil {
return err
}
break
} else if p.PersistentPreRun != nil {
p.PersistentPreRun(c, argWoFlags)
break
}
}
if c.PreRunE != nil {
if err := c.PreRunE(c, argWoFlags); err != nil {
return err
}
} else if c.PreRun != nil {
c.PreRun(c, argWoFlags)
}
if err := c.validateRequiredFlags(); err != nil {
return err
}
if c.RunE != nil {
if err := c.RunE(c, argWoFlags); err != nil {
return err
}
} else {
c.Run(c, argWoFlags)
}
if c.PostRunE != nil {
if err := c.PostRunE(c, argWoFlags); err != nil {
return err
}
} else if c.PostRun != nil {
c.PostRun(c, argWoFlags)
}
for p := c; p != nil; p = p.Parent() {
if p.PersistentPostRunE != nil {
if err := p.PersistentPostRunE(c, argWoFlags); err != nil {
return err
}
break
} else if p.PersistentPostRun != nil {
p.PersistentPostRun(c, argWoFlags)
break
}
}
return nil
}
func (c *Command) preRun() {
for _, x := range initializers {
x()
}
}
// Execute uses the args (os.Args[1:] by default)
// and run through the command tree finding appropriate matches
// for commands and then corresponding flags.
func (c *Command) Execute() error {
_, err := c.ExecuteC()
return err
}
// ExecuteC executes the command.
func (c *Command) ExecuteC() (cmd *Command, err error) {
// Regardless of what command execute is called on, run on Root only
if c.HasParent() {
return c.Root().ExecuteC()
}
// windows hook
if preExecHookFn != nil {
preExecHookFn(c)
}
// initialize help as the last point possible to allow for user
// overriding
c.InitDefaultHelpCmd()
var args []string
// Workaround FAIL with "go test -v" or "cobra.test -test.v", see #155
if c.args == nil && filepath.Base(os.Args[0]) != "cobra.test" {
args = os.Args[1:]
} else {
args = c.args
}
var flags []string
if c.TraverseChildren {
cmd, flags, err = c.Traverse(args)
} else {
cmd, flags, err = c.Find(args)
}
if err != nil {
// If found parse to a subcommand and then failed, talk about the subcommand
if cmd != nil {
c = cmd
}
if !c.SilenceErrors {
c.Println("Error:", err.Error())
c.Printf("Run '%v --help' for usage.\n", c.CommandPath())
}
return c, err
}
err = cmd.execute(flags)
if err != nil {
// Always show help if requested, even if SilenceErrors is in
// effect
if err == flag.ErrHelp {
cmd.HelpFunc()(cmd, args)
return cmd, nil
}
// If root command has SilentErrors flagged,
// all subcommands should respect it
if !cmd.SilenceErrors && !c.SilenceErrors {
c.Println("Error:", err.Error())
}
// If root command has SilentUsage flagged,
// all subcommands should respect it
if !cmd.SilenceUsage && !c.SilenceUsage {
c.Println(cmd.UsageString())
}
}
return cmd, err
}
func (c *Command) ValidateArgs(args []string) error {
if c.Args == nil {
return nil
}
return c.Args(c, args)
}
func (c *Command) validateRequiredFlags() error {
flags := c.Flags()
missingFlagNames := []string{}
flags.VisitAll(func(pflag *flag.Flag) {
requiredAnnotation, found := pflag.Annotations[BashCompOneRequiredFlag]
if !found {
return
}
if (requiredAnnotation[0] == "true") && !pflag.Changed {
missingFlagNames = append(missingFlagNames, pflag.Name)
}
})
if len(missingFlagNames) > 0 {
return fmt.Errorf(`Required flag(s) "%s" have/has not been set`, strings.Join(missingFlagNames, `", "`))
}
return nil
}
// InitDefaultHelpFlag adds default help flag to c.
// It is called automatically by executing the c or by calling help and usage.
// If c already has help flag, it will do nothing.
func (c *Command) InitDefaultHelpFlag() {
c.mergePersistentFlags()
if c.Flags().Lookup("help") == nil {
usage := "help for "
if c.Name() == "" {
usage += "this command"
} else {
usage += c.Name()
}
c.Flags().BoolP("help", "h", false, usage)
}
}
// InitDefaultHelpCmd adds default help command to c.
// It is called automatically by executing the c or by calling help and usage.
// If c already has help command or c has no subcommands, it will do nothing.
func (c *Command) InitDefaultHelpCmd() {
if !c.HasSubCommands() {
return
}
if c.helpCommand == nil {
c.helpCommand = &Command{
Use: "help [command]",
Short: "Help about any command",
Long: `Help provides help for any command in the application.
Simply type ` + c.Name() + ` help [path to command] for full details.`,
Run: func(c *Command, args []string) {
cmd, _, e := c.Root().Find(args)
if cmd == nil || e != nil {
c.Printf("Unknown help topic %#q\n", args)
c.Root().Usage()
} else {
cmd.InitDefaultHelpFlag() // make possible 'help' flag to be shown
cmd.Help()
}
},
}
}
c.RemoveCommand(c.helpCommand)
c.AddCommand(c.helpCommand)
}
// ResetCommands used for testing.
func (c *Command) ResetCommands() {
c.parent = nil
c.commands = nil
c.helpCommand = nil
c.parentsPflags = nil
}
// Sorts commands by their names.
type commandSorterByName []*Command
func (c commandSorterByName) Len() int { return len(c) }
func (c commandSorterByName) Swap(i, j int) { c[i], c[j] = c[j], c[i] }
func (c commandSorterByName) Less(i, j int) bool { return c[i].Name() < c[j].Name() }
// Commands returns a sorted slice of child commands.
func (c *Command) Commands() []*Command {
// do not sort commands if it already sorted or sorting was disabled
if EnableCommandSorting && !c.commandsAreSorted {
sort.Sort(commandSorterByName(c.commands))
c.commandsAreSorted = true
}
return c.commands
}
// AddCommand adds one or more commands to this parent command.
func (c *Command) AddCommand(cmds ...*Command) {
for i, x := range cmds {
if cmds[i] == c {
panic("Command can't be a child of itself")
}
cmds[i].parent = c
// update max lengths
usageLen := len(x.Use)
if usageLen > c.commandsMaxUseLen {
c.commandsMaxUseLen = usageLen
}
commandPathLen := len(x.CommandPath())
if commandPathLen > c.commandsMaxCommandPathLen {
c.commandsMaxCommandPathLen = commandPathLen
}
nameLen := len(x.Name())
if nameLen > c.commandsMaxNameLen {
c.commandsMaxNameLen = nameLen
}
// If global normalization function exists, update all children
if c.globNormFunc != nil {
x.SetGlobalNormalizationFunc(c.globNormFunc)
}
c.commands = append(c.commands, x)
c.commandsAreSorted = false
}
}
// RemoveCommand removes one or more commands from a parent command.
func (c *Command) RemoveCommand(cmds ...*Command) {
commands := []*Command{}
main:
for _, command := range c.commands {
for _, cmd := range cmds {
if command == cmd {
command.parent = nil
continue main
}
}
commands = append(commands, command)
}
c.commands = commands
// recompute all lengths
c.commandsMaxUseLen = 0
c.commandsMaxCommandPathLen = 0
c.commandsMaxNameLen = 0
for _, command := range c.commands {
usageLen := len(command.Use)
if usageLen > c.commandsMaxUseLen {
c.commandsMaxUseLen = usageLen
}
commandPathLen := len(command.CommandPath())
if commandPathLen > c.commandsMaxCommandPathLen {
c.commandsMaxCommandPathLen = commandPathLen
}
nameLen := len(command.Name())
if nameLen > c.commandsMaxNameLen {
c.commandsMaxNameLen = nameLen
}
}
}
// Print is a convenience method to Print to the defined output, fallback to Stderr if not set.
func (c *Command) Print(i ...interface{}) {
fmt.Fprint(c.OutOrStderr(), i...)
}
// Println is a convenience method to Println to the defined output, fallback to Stderr if not set.
func (c *Command) Println(i ...interface{}) {
c.Print(fmt.Sprintln(i...))
}
// Printf is a convenience method to Printf to the defined output, fallback to Stderr if not set.
func (c *Command) Printf(format string, i ...interface{}) {
c.Print(fmt.Sprintf(format, i...))
}
// CommandPath returns the full path to this command.
func (c *Command) CommandPath() string {
if c.HasParent() {
return c.Parent().CommandPath() + " " + c.Name()
}
return c.Name()
}
// UseLine puts out the full usage for a given command (including parents).
func (c *Command) UseLine() string {
var useline string
if c.HasParent() {
useline = c.parent.CommandPath() + " " + c.Use
} else {
useline = c.Use
}
if c.HasAvailableFlags() && !strings.Contains(useline, "[flags]") {
useline += " [flags]"
}
return useline
}
// DebugFlags used to determine which flags have been assigned to which commands
// and which persist.
func (c *Command) DebugFlags() {
c.Println("DebugFlags called on", c.Name())
var debugflags func(*Command)
debugflags = func(x *Command) {
if x.HasFlags() || x.HasPersistentFlags() {
c.Println(x.Name())
}
if x.HasFlags() {
x.flags.VisitAll(func(f *flag.Flag) {
if x.HasPersistentFlags() && x.persistentFlag(f.Name) != nil {
c.Println(" -"+f.Shorthand+",", "--"+f.Name, "["+f.DefValue+"]", "", f.Value, " [LP]")
} else {
c.Println(" -"+f.Shorthand+",", "--"+f.Name, "["+f.DefValue+"]", "", f.Value, " [L]")
}
})
}
if x.HasPersistentFlags() {
x.pflags.VisitAll(func(f *flag.Flag) {
if x.HasFlags() {
if x.flags.Lookup(f.Name) == nil {
c.Println(" -"+f.Shorthand+",", "--"+f.Name, "["+f.DefValue+"]", "", f.Value, " [P]")
}
} else {
c.Println(" -"+f.Shorthand+",", "--"+f.Name, "["+f.DefValue+"]", "", f.Value, " [P]")
}
})
}
c.Println(x.flagErrorBuf)
if x.HasSubCommands() {
for _, y := range x.commands {
debugflags(y)
}
}
}
debugflags(c)
}
// Name returns the command's name: the first word in the use line.
func (c *Command) Name() string {
name := c.Use
i := strings.Index(name, " ")
if i >= 0 {
name = name[:i]
}
return name
}
// HasAlias determines if a given string is an alias of the command.
func (c *Command) HasAlias(s string) bool {
for _, a := range c.Aliases {
if a == s {
return true
}
}
return false
}
// hasNameOrAliasPrefix returns true if the Name or any of aliases start
// with prefix
func (c *Command) hasNameOrAliasPrefix(prefix string) bool {
if strings.HasPrefix(c.Name(), prefix) {
return true
}
for _, alias := range c.Aliases {
if strings.HasPrefix(alias, prefix) {
return true
}
}
return false
}
// NameAndAliases returns a list of the command name and all aliases
func (c *Command) NameAndAliases() string {
return strings.Join(append([]string{c.Name()}, c.Aliases...), ", ")
}
// HasExample determines if the command has example.
func (c *Command) HasExample() bool {
return len(c.Example) > 0
}
// Runnable determines if the command is itself runnable.
func (c *Command) Runnable() bool {
return c.Run != nil || c.RunE != nil
}
// HasSubCommands determines if the command has children commands.
func (c *Command) HasSubCommands() bool {
return len(c.commands) > 0
}
// IsAvailableCommand determines if a command is available as a non-help command
// (this includes all non deprecated/hidden commands).
func (c *Command) IsAvailableCommand() bool {
if len(c.Deprecated) != 0 || c.Hidden {
return false
}
if c.HasParent() && c.Parent().helpCommand == c {
return false
}
if c.Runnable() || c.HasAvailableSubCommands() {
return true
}
return false
}
// IsAdditionalHelpTopicCommand determines if a command is an additional
// help topic command; additional help topic command is determined by the
// fact that it is NOT runnable/hidden/deprecated, and has no sub commands that
// are runnable/hidden/deprecated.
// Concrete example: https://github.com/spf13/cobra/issues/393#issuecomment-282741924.
func (c *Command) IsAdditionalHelpTopicCommand() bool {
// if a command is runnable, deprecated, or hidden it is not a 'help' command
if c.Runnable() || len(c.Deprecated) != 0 || c.Hidden {
return false
}
// if any non-help sub commands are found, the command is not a 'help' command
for _, sub := range c.commands {
if !sub.IsAdditionalHelpTopicCommand() {
return false
}
}
// the command either has no sub commands, or no non-help sub commands
return true
}
// HasHelpSubCommands determines if a command has any available 'help' sub commands
// that need to be shown in the usage/help default template under 'additional help
// topics'.
func (c *Command) HasHelpSubCommands() bool {
// return true on the first found available 'help' sub command
for _, sub := range c.commands {
if sub.IsAdditionalHelpTopicCommand() {
return true
}
}
// the command either has no sub commands, or no available 'help' sub commands
return false
}
// HasAvailableSubCommands determines if a command has available sub commands that
// need to be shown in the usage/help default template under 'available commands'.
func (c *Command) HasAvailableSubCommands() bool {
// return true on the first found available (non deprecated/help/hidden)
// sub command
for _, sub := range c.commands {
if sub.IsAvailableCommand() {
return true
}
}
// the command either has no sub comamnds, or no available (non deprecated/help/hidden)
// sub commands
return false
}
// HasParent determines if the command is a child command.
func (c *Command) HasParent() bool {
return c.parent != nil
}
// GlobalNormalizationFunc returns the global normalization function or nil if doesn't exists.
func (c *Command) GlobalNormalizationFunc() func(f *flag.FlagSet, name string) flag.NormalizedName {
return c.globNormFunc
}
// Flags returns the complete FlagSet that applies
// to this command (local and persistent declared here and by all parents).
func (c *Command) Flags() *flag.FlagSet {
if c.flags == nil {
c.flags = flag.NewFlagSet(c.Name(), flag.ContinueOnError)
if c.flagErrorBuf == nil {
c.flagErrorBuf = new(bytes.Buffer)
}
c.flags.SetOutput(c.flagErrorBuf)
}
return c.flags
}
// LocalNonPersistentFlags are flags specific to this command which will NOT persist to subcommands.
func (c *Command) LocalNonPersistentFlags() *flag.FlagSet {
persistentFlags := c.PersistentFlags()
out := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
c.LocalFlags().VisitAll(func(f *flag.Flag) {
if persistentFlags.Lookup(f.Name) == nil {
out.AddFlag(f)
}
})
return out
}
// LocalFlags returns the local FlagSet specifically set in the current command.
func (c *Command) LocalFlags() *flag.FlagSet {
c.mergePersistentFlags()
if c.lflags == nil {
c.lflags = flag.NewFlagSet(c.Name(), flag.ContinueOnError)
if c.flagErrorBuf == nil {
c.flagErrorBuf = new(bytes.Buffer)
}
c.lflags.SetOutput(c.flagErrorBuf)
}
c.lflags.SortFlags = c.Flags().SortFlags
if c.globNormFunc != nil {
c.lflags.SetNormalizeFunc(c.globNormFunc)
}
addToLocal := func(f *flag.Flag) {
if c.lflags.Lookup(f.Name) == nil && c.parentsPflags.Lookup(f.Name) == nil {
c.lflags.AddFlag(f)
}
}
c.Flags().VisitAll(addToLocal)
c.PersistentFlags().VisitAll(addToLocal)
return c.lflags
}
// InheritedFlags returns all flags which were inherited from parents commands.
func (c *Command) InheritedFlags() *flag.FlagSet {
c.mergePersistentFlags()
if c.iflags == nil {
c.iflags = flag.NewFlagSet(c.Name(), flag.ContinueOnError)
if c.flagErrorBuf == nil {
c.flagErrorBuf = new(bytes.Buffer)
}
c.iflags.SetOutput(c.flagErrorBuf)
}
local := c.LocalFlags()
if c.globNormFunc != nil {
c.iflags.SetNormalizeFunc(c.globNormFunc)
}
c.parentsPflags.VisitAll(func(f *flag.Flag) {
if c.iflags.Lookup(f.Name) == nil && local.Lookup(f.Name) == nil {
c.iflags.AddFlag(f)
}
})
return c.iflags
}
// NonInheritedFlags returns all flags which were not inherited from parent commands.
func (c *Command) NonInheritedFlags() *flag.FlagSet {
return c.LocalFlags()
}
// PersistentFlags returns the persistent FlagSet specifically set in the current command.
func (c *Command) PersistentFlags() *flag.FlagSet {
if c.pflags == nil {
c.pflags = flag.NewFlagSet(c.Name(), flag.ContinueOnError)
if c.flagErrorBuf == nil {
c.flagErrorBuf = new(bytes.Buffer)
}
c.pflags.SetOutput(c.flagErrorBuf)
}
return c.pflags
}
// ResetFlags is used in testing.
func (c *Command) ResetFlags() {
c.flagErrorBuf = new(bytes.Buffer)
c.flagErrorBuf.Reset()
c.flags = flag.NewFlagSet(c.Name(), flag.ContinueOnError)
c.flags.SetOutput(c.flagErrorBuf)
c.pflags = flag.NewFlagSet(c.Name(), flag.ContinueOnError)
c.pflags.SetOutput(c.flagErrorBuf)
c.lflags = nil
c.iflags = nil
c.parentsPflags = nil
}
// HasFlags checks if the command contains any flags (local plus persistent from the entire structure).
func (c *Command) HasFlags() bool {
return c.Flags().HasFlags()
}
// HasPersistentFlags checks if the command contains persistent flags.
func (c *Command) HasPersistentFlags() bool {
return c.PersistentFlags().HasFlags()
}
// HasLocalFlags checks if the command has flags specifically declared locally.
func (c *Command) HasLocalFlags() bool {
return c.LocalFlags().HasFlags()
}
// HasInheritedFlags checks if the command has flags inherited from its parent command.
func (c *Command) HasInheritedFlags() bool {
return c.InheritedFlags().HasFlags()
}
// HasAvailableFlags checks if the command contains any flags (local plus persistent from the entire
// structure) which are not hidden or deprecated.
func (c *Command) HasAvailableFlags() bool {
return c.Flags().HasAvailableFlags()
}
// HasAvailablePersistentFlags checks if the command contains persistent flags which are not hidden or deprecated.
func (c *Command) HasAvailablePersistentFlags() bool {
return c.PersistentFlags().HasAvailableFlags()
}
// HasAvailableLocalFlags checks if the command has flags specifically declared locally which are not hidden
// or deprecated.
func (c *Command) HasAvailableLocalFlags() bool {
return c.LocalFlags().HasAvailableFlags()
}
// HasAvailableInheritedFlags checks if the command has flags inherited from its parent command which are
// not hidden or deprecated.
func (c *Command) HasAvailableInheritedFlags() bool {
return c.InheritedFlags().HasAvailableFlags()
}
// Flag climbs up the command tree looking for matching flag.
func (c *Command) Flag(name string) (flag *flag.Flag) {
flag = c.Flags().Lookup(name)
if flag == nil {
flag = c.persistentFlag(name)
}
return
}
// Recursively find matching persistent flag.
func (c *Command) persistentFlag(name string) (flag *flag.Flag) {
if c.HasPersistentFlags() {
flag = c.PersistentFlags().Lookup(name)
}
if flag == nil {
c.updateParentsPflags()
flag = c.parentsPflags.Lookup(name)
}
return
}
// ParseFlags parses persistent flag tree and local flags.
func (c *Command) ParseFlags(args []string) error {
if c.DisableFlagParsing {
return nil
}
if c.flagErrorBuf == nil {
c.flagErrorBuf = new(bytes.Buffer)
}
beforeErrorBufLen := c.flagErrorBuf.Len()
c.mergePersistentFlags()
err := c.Flags().Parse(args)
// Print warnings if they occurred (e.g. deprecated flag messages).
if c.flagErrorBuf.Len()-beforeErrorBufLen > 0 && err == nil {
c.Print(c.flagErrorBuf.String())
}
return err
}
// Parent returns a commands parent command.
func (c *Command) Parent() *Command {
return c.parent
}
// mergePersistentFlags merges c.PersistentFlags() to c.Flags()
// and adds missing persistent flags of all parents.
func (c *Command) mergePersistentFlags() {
c.updateParentsPflags()
c.Flags().AddFlagSet(c.PersistentFlags())
c.Flags().AddFlagSet(c.parentsPflags)
}
// updateParentsPflags updates c.parentsPflags by adding
// new persistent flags of all parents.
// If c.parentsPflags == nil, it makes new.
func (c *Command) updateParentsPflags() {
if c.parentsPflags == nil {
c.parentsPflags = flag.NewFlagSet(c.Name(), flag.ContinueOnError)
c.parentsPflags.SetOutput(c.flagErrorBuf)
c.parentsPflags.SortFlags = false
}
if c.globNormFunc != nil {
c.parentsPflags.SetNormalizeFunc(c.globNormFunc)
}
c.Root().PersistentFlags().AddFlagSet(flag.CommandLine)
c.VisitParents(func(parent *Command) {
c.parentsPflags.AddFlagSet(parent.PersistentFlags())
})
}