lxd/cluster/events.go
func Events(endpoints *endpoints.Endpoints, cluster *db.Cluster, f func(int64, api.Event)) (task.Func, task.Schedule) {
	listeners := map[int64]*lxd.EventListener{}

	// Update our pool of event listeners. Since database queries are
	// blocking, we spawn the actual logic in a goroutine, to abort
	// immediately when we receive the stop signal.
	update := func(ctx context.Context) {
		ch := make(chan struct{})
		go func() {
			eventsUpdateListeners(endpoints, cluster, listeners, f)
			ch <- struct{}{}
		}()
		select {
		case <-ch:
		case <-ctx.Done():
		}

	}

	schedule := task.Every(time.Second)

	return update, schedule
}
func Events(endpoints *endpoints.Endpoints, cluster *db.Cluster, f func(int64, api.Event)) (task.Func, task.Schedule) {
	listeners := map[int64]*lxd.EventListener{}

	// Update our pool of event listeners. Since database queries are
	// blocking, we spawn the actual logic in a goroutine, to abort
	// immediately when we receive the stop signal.
	update := func(ctx context.Context) {
		ch := make(chan struct{})
		go func() {
			eventsUpdateListeners(endpoints, cluster, listeners, f)
			ch <- struct{}{}
		}()
		select {
		case <-ch:
		case <-ctx.Done():
		}

	}

	schedule := task.Every(time.Second)

	return update, schedule
}
// Events starts a task that continuously monitors the list of cluster nodes and
// maintains a pool of websocket connections against all of them, in order to
// get notified about events.
//
// Whenever an event is received the given callback is invoked.