handler

Documentation

Index

• type IO
  • func (h *IO) Err() io.Writer
  • func (h *IO) Exit(code int, a ...interface{})
  • func (h *IO) ExitOnErr(err error, msg string, code int)
  • func (h *IO) ExitOnErrShort(err error, msg string, code int)
  • func (h *IO) ExitOnErrsShort(errs []error, code int)
  • func (h *IO) Exitf(code int, format string, a ...interface{})
  • func (h *IO) In() io.Reader
  • func (h *IO) OnSignal(s os.Signal, f func(os.Signal)) (cancel func())
  • func (h *IO) Out() io.Writer
  • func (h *IO) SetErr(w io.Writer)
  • func (h *IO) SetIn(r io.Reader)
  • func (h *IO) SetOut(w io.Writer)
• type Mixin
• type PostRun
• type PreRun
• type Responder

Types

type IO

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

IO can be embedded in all mixins and sub-command handlers and provide a default implementation of the Responder interface.

func (*IO) Err

func (h *IO) Err() io.Writer

func (*IO) Exit

func (h *IO) Exit(code int, a ...interface{})

func (*IO) ExitOnErr

func (h *IO) ExitOnErr(err error, msg string, code int)

func (*IO) ExitOnErrShort

func (h *IO) ExitOnErrShort(err error, msg string, code int)

func (*IO) ExitOnErrsShort

func (h *IO) ExitOnErrsShort(errs []error, code int)

func (*IO) Exitf

func (h *IO) Exitf(code int, format string, a ...interface{})

func (*IO) In

func (h *IO) In() io.Reader

func (*IO) OnSignal

func (h *IO) OnSignal(s os.Signal, f func(os.Signal)) (cancel func())

func (*IO) Out

func (h *IO) Out() io.Writer

func (*IO) SetErr

func (h *IO) SetErr(w io.Writer)

func (*IO) SetIn

func (h *IO) SetIn(r io.Reader)

func (*IO) SetOut

func (h *IO) SetOut(w io.Writer)

type Mixin

type Mixin interface {
	// BindCobraFlags gives each mixin the opportunity to define its own flags.
	BindCobraFlags(cmd *cobra.Command) (requiredFlags []string)

	// Name should identify the mixin for use in error/log messages.
	//
	// Ideally it is short, e.g. like a package name.
	Name() string
}

type PostRun

type PostRun interface {
	PostRun(ctx context.Context)
}

PostRun is optionally implemented by handlers/mixins to perform tasks after Handler.Run finishes.

type PreRun

type PreRun interface {
	PreRun(ctx context.Context, args []string) error
}

PreRun is optionally implemented by handlers/mixins to perform tasks after flags are parsed but before Handler.Run.

If it returns an error, Handler.Run and Handler.PostRun do not execute.

type Responder

type Responder interface {
	// Err returns the standard error destination.
	Err() io.Writer

	// In returns the standard input source.
	In() io.Reader

	// OnSignal starts a goroutine which runs the provided function every time the signal
	// is received. It returns a function to end the goroutine.
	OnSignal(s os.Signal, do func(os.Signal)) (cancel func())

	// Out returns the standard output destination.
	Out() io.Writer

	// SetErr assigns the standard error destination.
	SetErr(io.Writer)

	// SetIn assigns the standard input source.
	SetIn(io.Reader)

	// SetOut assigns the standard error destination.
	SetOut(io.Writer)
}

Responder defines the common response behavior expected from each sub-command implementation.

Behaviors related to terminal I/O are based on the approached used in docker itself (e.g. ClI interface): https://github.com/docker/cli/blob/f1b116179f2a95d0ea45780dfb8be51c2825b9c0/cli/command/cli.go. Specifically, Out and Err methods are intended to improve testability by expecting that terminal messages can be captured for assertions about their content (as they are in docker's own CLI tests).