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- import { async } from '../scheduler/async';
- import { isDate } from '../util/isDate';
- import { OuterSubscriber } from '../OuterSubscriber';
- import { subscribeToResult } from '../util/subscribeToResult';
- /* tslint:enable:max-line-length */
- /**
- *
- * Errors if Observable does not emit a value in given time span, in case of which
- * subscribes to the second Observable.
- *
- * <span class="informal">It's a version of `timeout` operator that let's you specify fallback Observable.</span>
- *
- * <img src="./img/timeoutWith.png" width="100%">
- *
- * `timeoutWith` is a variation of `timeout` operator. It behaves exactly the same,
- * still accepting as a first argument either a number or a Date, which control - respectively -
- * when values of source Observable should be emitted or when it should complete.
- *
- * The only difference is that it accepts a second, required parameter. This parameter
- * should be an Observable which will be subscribed when source Observable fails any timeout check.
- * So whenever regular `timeout` would emit an error, `timeoutWith` will instead start re-emitting
- * values from second Observable. Note that this fallback Observable is not checked for timeouts
- * itself, so it can emit values and complete at arbitrary points in time. From the moment of a second
- * subscription, Observable returned from `timeoutWith` simply mirrors fallback stream. When that
- * stream completes, it completes as well.
- *
- * Scheduler, which in case of `timeout` is provided as as second argument, can be still provided
- * here - as a third, optional parameter. It still is used to schedule timeout checks and -
- * as a consequence - when second Observable will be subscribed, since subscription happens
- * immediately after failing check.
- *
- * @example <caption>Add fallback observable</caption>
- * const seconds = Rx.Observable.interval(1000);
- * const minutes = Rx.Observable.interval(60 * 1000);
- *
- * seconds.timeoutWith(900, minutes)
- * .subscribe(
- * value => console.log(value), // After 900ms, will start emitting `minutes`,
- * // since first value of `seconds` will not arrive fast enough.
- * err => console.log(err) // Would be called after 900ms in case of `timeout`,
- * // but here will never be called.
- * );
- *
- * @param {number|Date} due Number specifying period within which Observable must emit values
- * or Date specifying before when Observable should complete
- * @param {Observable<T>} withObservable Observable which will be subscribed if source fails timeout check.
- * @param {Scheduler} [scheduler] Scheduler controlling when timeout checks occur.
- * @return {Observable<T>} Observable that mirrors behaviour of source or, when timeout check fails, of an Observable
- * passed as a second parameter.
- * @method timeoutWith
- * @owner Observable
- */
- export function timeoutWith(due, withObservable, scheduler = async) {
- return (source) => {
- let absoluteTimeout = isDate(due);
- let waitFor = absoluteTimeout ? (+due - scheduler.now()) : Math.abs(due);
- return source.lift(new TimeoutWithOperator(waitFor, absoluteTimeout, withObservable, scheduler));
- };
- }
- class TimeoutWithOperator {
- constructor(waitFor, absoluteTimeout, withObservable, scheduler) {
- this.waitFor = waitFor;
- this.absoluteTimeout = absoluteTimeout;
- this.withObservable = withObservable;
- this.scheduler = scheduler;
- }
- call(subscriber, source) {
- return source.subscribe(new TimeoutWithSubscriber(subscriber, this.absoluteTimeout, this.waitFor, this.withObservable, this.scheduler));
- }
- }
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
- class TimeoutWithSubscriber extends OuterSubscriber {
- constructor(destination, absoluteTimeout, waitFor, withObservable, scheduler) {
- super(destination);
- this.absoluteTimeout = absoluteTimeout;
- this.waitFor = waitFor;
- this.withObservable = withObservable;
- this.scheduler = scheduler;
- this.action = null;
- this.scheduleTimeout();
- }
- static dispatchTimeout(subscriber) {
- const { withObservable } = subscriber;
- subscriber._unsubscribeAndRecycle();
- subscriber.add(subscribeToResult(subscriber, withObservable));
- }
- 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(TimeoutWithSubscriber.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.withObservable = null;
- }
- }
- //# sourceMappingURL=timeoutWith.js.map
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