command

Documentation

Index

• func DoNothing(_ Context) error
• type Action
• type Command
  • func New(helpShort HelpShort, action Action, opts ...CommandOpt) Command
• type CommandMap
  • func (fm CommandMap) Empty() bool
  • func (fm CommandMap) SortedNames() []Name
• type CommandOpt
  • func ExistingFlag(name flag.Name, value flag.Flag) CommandOpt
  • func ExistingFlags(flagMap flag.FlagMap) CommandOpt
  • func Flag(name flag.Name, helpShort flag.HelpShort, empty value.EmptyConstructor, ...) CommandOpt
  • func Footer(footer string) CommandOpt
  • func HelpLong(helpLong string) CommandOpt
• type Context
• type HelpShort
• type Name
• type PassedFlags

Functions

func DoNothing

func DoNothing(_ Context) error

DoNothing is a command action that simply returns an error. Useful for prototyping

Types

type Action

type Action func(Context) error

An Action is run as the result of a command

type Command

type Command struct {
	// Action to run when command is invoked
	Action Action

	// Parsed Flags
	Flags flag.FlagMap

	// Footer is yet another optional longer description.
	Footer string

	// HelpLong is an optional longer description
	HelpLong string

	// HelpShort is a required one-line description
	HelpShort HelpShort
}

A Command will run code for you! The name of a Command should probably be a verb - add , edit, run, ... A Command should not be constructed directly. Use Command / New / ExistingCommand functions

func New

func New(helpShort HelpShort, action Action, opts ...CommandOpt) Command

New builds a Command

type CommandMap

type CommandMap map[Name]Command

A CommandMap holds Commands and is used by Sections

func (CommandMap) Empty

func (fm CommandMap) Empty() bool

func (CommandMap) SortedNames

func (fm CommandMap) SortedNames() []Name

type CommandOpt

type CommandOpt func(*Command)

A CommandOpt customizes a Command

func ExistingFlag

func ExistingFlag(name flag.Name, value flag.Flag) CommandOpt

ExistingFlag adds an existing flag to a Command. It panics if a flag with the same name exists

func ExistingFlags

func ExistingFlags(flagMap flag.FlagMap) CommandOpt

func Flag

func Flag(name flag.Name, helpShort flag.HelpShort, empty value.EmptyConstructor, opts ...flag.FlagOpt) CommandOpt

Flag builds a flag and adds it to a Command. It panics if a flag with the same name exists

func Footer

func Footer(footer string) CommandOpt

Footer adds an Help string to the command - useful from a help function

func HelpLong

func HelpLong(helpLong string) CommandOpt

HelpLong adds an Help string to the command - useful from a help function

type Context

type Context struct {
	AppName string

	// Context to smuggle user-defined state (i.e., not flags) into an Action. I use this for mocks when testing
	Context context.Context
	Flags   PassedFlags

	// Path passed either to a command or a section. Does not include executable name (os.Args[0])
	Path   []string
	Stderr *os.File
	Stdout *os.File

	// Version of this app
	Version string
}

Context holds everything a command needs.

type HelpShort

type HelpShort string

type Name

type Name string

Name of the command

type PassedFlags

type PassedFlags map[string]interface{} // This can just stay a string for the convenience of the user.

PassedFlags holds a map of flag names to flag Values