watcher

Documentation

Overview

Package watcher provides file update notification functionality as a module.

Index

• Variables
• type Opt
  • func WithFunc(fn func() error) Opt
  • func WithTarget(fileOrDirName string) Opt
• type Watcher
  • func New(opts ...Opt) *Watcher
  • func (w *Watcher) Init() error
  • func (w *Watcher) Name() string
  • func (w *Watcher) Run() error
  • func (w *Watcher) Stop() error

Examples

• New

Variables

var (
	ErrMissingWithTarget = fmt.Errorf("watcher.Watcher missing or empty WithTarget option")
	ErrMissingWithFunc   = fmt.Errorf("watcher.Watcher missing WithFunc option")
)

Types

type Opt

type Opt func(*Watcher) error

func WithFunc

func WithFunc(fn func() error) Opt

func WithTarget

func WithTarget(fileOrDirName string) Opt

type Watcher

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

func New

func New(opts ...Opt) *Watcher

New creates watcher with given options. WithTarget and WithFunc options are mandatory.

Example

tmpFile, err := os.CreateTemp("", testFilePattern)
if err != nil {
	fmt.Println(err)
	return
}
defer os.Remove(tmpFile.Name())

t := ticker.New(
	ticker.WithInterval(time.Second),
	ticker.WithFunc(func() error {
		_, err = tmpFile.Write([]byte("updated"))
		if err != nil {
			return err
		}
		return nil
	}),
)

w := watcher.New(
	watcher.WithTarget(tmpFile.Name()),
	watcher.WithFunc(func() error {
		slog.Info("Hello from watcher")
		return errors.New("watcher error")
	}),
)

err = service.Run(service.Modules{t, w})
if err != nil {
	fmt.Println(err)
}

Output:

1 error occurred:
	* failed to run module watcher.Watcher: watcher error

func (*Watcher) Init

func (w *Watcher) Init() error

func (*Watcher) Name

func (w *Watcher) Name() string

func (*Watcher) Run

func (w *Watcher) Run() error

func (*Watcher) Stop

func (w *Watcher) Stop() error