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- import { async } from '../scheduler/async';
- import { isDate } from '../util/isDate';
- import { Subscriber } from '../Subscriber';
- import { TimeoutError } from '../util/TimeoutError';
- /**
- *
- * 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) {
- const absoluteTimeout = isDate(due);
- const waitFor = absoluteTimeout ? (+due - scheduler.now()) : Math.abs(due);
- return (source) => source.lift(new TimeoutOperator(waitFor, absoluteTimeout, scheduler, new TimeoutError()));
- }
- class TimeoutOperator {
- constructor(waitFor, absoluteTimeout, scheduler, errorInstance) {
- this.waitFor = waitFor;
- this.absoluteTimeout = absoluteTimeout;
- this.scheduler = scheduler;
- this.errorInstance = errorInstance;
- }
- call(subscriber, source) {
- return source.subscribe(new TimeoutSubscriber(subscriber, this.absoluteTimeout, this.waitFor, this.scheduler, this.errorInstance));
- }
- }
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
- class TimeoutSubscriber extends Subscriber {
- constructor(destination, absoluteTimeout, waitFor, scheduler, errorInstance) {
- super(destination);
- this.absoluteTimeout = absoluteTimeout;
- this.waitFor = waitFor;
- this.scheduler = scheduler;
- this.errorInstance = errorInstance;
- this.action = null;
- this.scheduleTimeout();
- }
- static dispatchTimeout(subscriber) {
- subscriber.error(subscriber.errorInstance);
- }
- scheduleTimeout() {
- const { action } = this;
- if (action) {
- // Recycle the action if we've already scheduled one. All the production
- // Scheduler Actions mutate their state/delay time and return themeselves.
- // VirtualActions are immutable, so they create and return a clone. In this
- // case, we need to set the action reference to the most recent VirtualAction,
- // to ensure that's the one we clone from next time.
- this.action = action.schedule(this, this.waitFor);
- }
- else {
- this.add(this.action = this.scheduler.schedule(TimeoutSubscriber.dispatchTimeout, this.waitFor, this));
- }
- }
- _next(value) {
- if (!this.absoluteTimeout) {
- this.scheduleTimeout();
- }
- super._next(value);
- }
- /** @deprecated internal use only */ _unsubscribe() {
- this.action = null;
- this.scheduler = null;
- this.errorInstance = null;
- }
- }
- //# sourceMappingURL=timeout.js.map
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