watchmanager

type Options interface {
	// Watcher is the etcd watcher
	Watcher() clientv3.Watcher
	// SetWatcher sets the Watcher
	SetWatcher(w clientv3.Watcher) Options

	// UpdateFn is the function called when a notification on a key is received
	UpdateFn() UpdateFn
	// SetUpdateFn sets the UpdateFn
	SetUpdateFn(f UpdateFn) Options

	// TickAndStopFn is the function called periodically to check if a watch should be stopped
	TickAndStopFn() TickAndStopFn
	// SetTickAndStopFn sets the TickAndStopFn
	SetTickAndStopFn(f TickAndStopFn) Options

	// WatchOptions is a set of options for the etcd watch
	WatchOptions() []clientv3.OpOption
	// SetWatchOptions sets the WatchOptions
	SetWatchOptions(opts []clientv3.OpOption) Options

	// WatchChanCheckInterval will be used to periodically check if a watch chan
	// is no longer being subscribed and should be closed
	WatchChanCheckInterval() time.Duration
	// SetWatchChanCheckInterval sets the WatchChanCheckInterval
	SetWatchChanCheckInterval(t time.Duration) Options

	// WatchChanResetInterval is the delay before resetting the etcd watch chan
	WatchChanResetInterval() time.Duration
	// SetWatchChanResetInterval sets the WatchChanResetInterval
	SetWatchChanResetInterval(t time.Duration) Options

	// WatchChanInitTimeout is the timeout for a watchChan initialization
	WatchChanInitTimeout() time.Duration
	// SetWatchChanInitTimeout sets the WatchChanInitTimeout
	SetWatchChanInitTimeout(t time.Duration) Options

	// InstrumentsOptions is the instrument options
	InstrumentsOptions() instrument.Options
	// SetInstrumentsOptions sets the InstrumentsOptions
	SetInstrumentsOptions(iopts instrument.Options) Options

	// Validate validates the options
	Validate() error
}

type TickAndStopFn func(key string) bool

type UpdateFn func(key string, events []*clientv3.Event) error

type WatchManager interface {
	// Watch watches the key forever until the CheckAndStopFn returns true
	Watch(key string)
}