moby/pkg/filenotify/filenotify.go
Brian Goff f78091897a Revert "pkg: remove unused filenotify"
This reverts commit ee99b5f2e9.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2016-02-23 21:43:46 -05:00

40 lines
1.2 KiB
Go

// Package filenotify provides a mechanism for watching file(s) for changes.
// Generally leans on fsnotify, but provides a poll-based notifier which fsnotify does not support.
// These are wrapped up in a common interface so that either can be used interchangeably in your code.
package filenotify
import "gopkg.in/fsnotify.v1"
// FileWatcher is an interface for implementing file notification watchers
type FileWatcher interface {
Events() <-chan fsnotify.Event
Errors() <-chan error
Add(name string) error
Remove(name string) error
Close() error
}
// New tries to use an fs-event watcher, and falls back to the poller if there is an error
func New() (FileWatcher, error) {
if watcher, err := NewEventWatcher(); err == nil {
return watcher, nil
}
return NewPollingWatcher(), nil
}
// NewPollingWatcher returns a poll-based file watcher
func NewPollingWatcher() FileWatcher {
return &filePoller{
events: make(chan fsnotify.Event),
errors: make(chan error),
}
}
// NewEventWatcher returns an fs-event based file watcher
func NewEventWatcher() (FileWatcher, error) {
watcher, err := fsnotify.NewWatcher()
if err != nil {
return nil, err
}
return &fsNotifyWatcher{watcher}, nil
}