Configuration Options.
Triggered on any change in the number of subscriptions.
Current number of live subscriptions.
Maximum number of subscribers that can receive events.
Default is 0, meaning no limit applies.
Newer subscriptions outside of the maximum quota will start receiving events when the older subscriptions get cancelled.
It can only be set with the constructor.
Cancels all existing subscriptions for the event.
It overrides the base implementation, to trigger event onCount when there was at least one subscription.
Number of subscriptions cancelled.
Broadcasts data to all subscribers, according to the emit schedule, which is synchronous by default.
Data to be sent, according to the template type.
Event-emitting options.
The event object itself.
Retrieves subscriptions statistics, to help with diagnosing subscription leaks.
For this method to be useful, you need to set option name when calling subscribe.
See also: Diagnostics
Statistics Options:
minUse: number - Minimum subscription usage/count to be included into the list of named
subscriptions. If subscription is used less times, it will be excluded from the named list.Subscribes to receive just one event, and cancel the subscription immediately.
You may still want to call cancel on the returned Subscription object, if you suddenly need to prevent the first event, or to avoid dead once-off subscriptions that never received their event, and thus were not cancelled.
Event notification function, invoked after self-cancelling the subscription.
Subscription Options.
Object for cancelling the subscription safely.
Subscribes to the event.
When subscription is no longer needed, method cancel should be called on the returned object, to avoid performance degradation caused by abandoned subscribers.
Method getStat can help with diagnosing leaked subscriptions.
Event notification callback function.
Subscription Options.
Object for cancelling the subscription safely.
Returns a new EventConsumer for the event, which physically hides methods emit and cancelAll.
This method simplifies creation of a receive-only event object representation.
const e = new SubEvent<number>(); // full-access, emit-receive event
const c = e.toConsumer(); // the same "e" event, but with receive-only access
// It is equivalent to the full syntax of:
// const c = new EventConsumer<number>(e);
Creates a new subscription as a promise, to resolve with the next received event value, and cancel the subscription.
Examples of where it can be useful include:
try {
const nextValue = await myEvent.toPromise({timeout: 1000});
} catch(e) {
// Either subscription didn't produce any event after 1 second,
// or myEvent.cancelAll() was called somewhere.
}
The returned promise can reject in two cases:
timeout), it rejects with Event timed out error;Event cancelled error.Note that if you use this method consecutively, you can miss events in between, because the subscription is auto-cancelled after receiving the first event.
Subscription Options:
name - for the internal subscription name. See name in ISubOptions.
In this context, it is also included within any rejection error.
timeout - sets timeout in ms (when timeout >= 0), to auto-reject with
Event timed out error.
Generated using TypeDoc
class SubEventCount<T = unknown> extends SubEvent<T>
Extends SubEvent with event onCount, to observe the number of subscriptions.