71 lines
3.5 KiB
JavaScript
71 lines
3.5 KiB
JavaScript
import { async } from '../scheduler/async';
|
|
import { timeout as higherOrder } from '../operators/timeout';
|
|
/**
|
|
*
|
|
* Errors if Observable does not emit a value in given time span.
|
|
*
|
|
* <span class="informal">Timeouts on Observable that doesn't emit values fast enough.</span>
|
|
*
|
|
* <img src="./img/timeout.png" width="100%">
|
|
*
|
|
* `timeout` operator accepts as an argument either a number or a Date.
|
|
*
|
|
* If number was provided, it returns an Observable that behaves like a source
|
|
* Observable, unless there is a period of time where there is no value emitted.
|
|
* So if you provide `100` as argument and first value comes after 50ms from
|
|
* the moment of subscription, this value will be simply re-emitted by the resulting
|
|
* Observable. If however after that 100ms passes without a second value being emitted,
|
|
* stream will end with an error and source Observable will be unsubscribed.
|
|
* These checks are performed throughout whole lifecycle of Observable - from the moment
|
|
* it was subscribed to, until it completes or errors itself. Thus every value must be
|
|
* emitted within specified period since previous value.
|
|
*
|
|
* If provided argument was Date, returned Observable behaves differently. It throws
|
|
* if Observable did not complete before provided Date. This means that periods between
|
|
* emission of particular values do not matter in this case. If Observable did not complete
|
|
* before provided Date, source Observable will be unsubscribed. Other than that, resulting
|
|
* stream behaves just as source Observable.
|
|
*
|
|
* `timeout` accepts also a Scheduler as a second parameter. It is used to schedule moment (or moments)
|
|
* when returned Observable will check if source stream emitted value or completed.
|
|
*
|
|
* @example <caption>Check if ticks are emitted within certain timespan</caption>
|
|
* const seconds = Rx.Observable.interval(1000);
|
|
*
|
|
* seconds.timeout(1100) // Let's use bigger timespan to be safe,
|
|
* // since `interval` might fire a bit later then scheduled.
|
|
* .subscribe(
|
|
* value => console.log(value), // Will emit numbers just as regular `interval` would.
|
|
* err => console.log(err) // Will never be called.
|
|
* );
|
|
*
|
|
* seconds.timeout(900).subscribe(
|
|
* value => console.log(value), // Will never be called.
|
|
* err => console.log(err) // Will emit error before even first value is emitted,
|
|
* // since it did not arrive within 900ms period.
|
|
* );
|
|
*
|
|
* @example <caption>Use Date to check if Observable completed</caption>
|
|
* const seconds = Rx.Observable.interval(1000);
|
|
*
|
|
* seconds.timeout(new Date("December 17, 2020 03:24:00"))
|
|
* .subscribe(
|
|
* value => console.log(value), // Will emit values as regular `interval` would
|
|
* // until December 17, 2020 at 03:24:00.
|
|
* err => console.log(err) // On December 17, 2020 at 03:24:00 it will emit an error,
|
|
* // since Observable did not complete by then.
|
|
* );
|
|
*
|
|
* @see {@link timeoutWith}
|
|
*
|
|
* @param {number|Date} due Number specifying period within which Observable must emit values
|
|
* or Date specifying before when Observable should complete
|
|
* @param {Scheduler} [scheduler] Scheduler controlling when timeout checks occur.
|
|
* @return {Observable<T>} Observable that mirrors behaviour of source, unless timeout checks fail.
|
|
* @method timeout
|
|
* @owner Observable
|
|
*/
|
|
export function timeout(due, scheduler = async) {
|
|
return higherOrder(due, scheduler)(this);
|
|
}
|
|
//# sourceMappingURL=timeout.js.map
|