tool

Documentation

Overview

Package tool is used for parsing input parameters, and starting subcommands (aka tools).

Index

• type Context
  • func NewContext(handlers ...Handler) *Context
  • func (c *Context) Run(args []string) error
• type Data
  • func (a Data) GetDefault(i int, defaultVal string) string
• type Handler
  • func (h Handler) Requested(args []string) ([]string, bool)

Types

type Context

type Context struct {
	// contains filtered or unexported fields
}

Context stores information about available subcommands (aka tools) and other related things that are necessary for their start.

func NewContext

func NewContext(handlers ...Handler) *Context

NewContext gets a number of handlers as arguments, allocates a new Context and returns it.

func (*Context) Run

func (c *Context) Run(args []string) error

Run gets a list of arguments and either starts an entry function of the requested subcommand (aka tool) or returns an error.

type Data

type Data []string

Data represents a set of non-flag arguments for a tool.

func (Data) GetDefault

func (a Data) GetDefault(i int, defaultVal string) string

GetDefault is a helper for getting a value with specific index or returning a default value if the index does not exist.

type Handler

type Handler struct {
	// Run is an entry function of the handler.
	// The args are the arguments after the command name.
	Run func(hs []Handler, i int, args Data)

	// Default means the handler must be executed if no arguments are
	// received from user (in addition to when it is called explicitly).
	// Only first default handler is used, others will be ignored.
	Default bool

	Name  string // Name of the handler, e.g. "new" or "generate stuff".
	Usage string // Possible arguments of the command, e.g. "[input] [output]".
	Info  string // One line description of the command.
	Desc  string // Detailed description of what the command does.

	Flags flag.FlagSet // Set of flags specific to the command.
}

Handler is a type for representation of a subcommand (aka tool) such as "cli run" or "cli new".

func (Handler) Requested

func (h Handler) Requested(args []string) ([]string, bool)

Requested checks whether the handler is the one that is requested by user, i.e. handler's name or alias is a part of args. It returns arguments (not including the handler name) and true in case of success, and nil, false otherwise.