111 lines
3.9 KiB
JavaScript
111 lines
3.9 KiB
JavaScript
|
import { root } from '../util/root';
|
||
|
|
import { Observable } from '../Observable';
|
||
|
|
/**
|
||
|
|
* We need this JSDoc comment for affecting ESDoc.
|
||
|
|
* @extends {Ignored}
|
||
|
|
* @hide true
|
||
|
|
*/
|
||
|
|
export class PromiseObservable extends Observable {
|
||
|
|
constructor(promise, scheduler) {
|
||
|
|
super();
|
||
|
|
this.promise = promise;
|
||
|
|
this.scheduler = scheduler;
|
||
|
|
}
|
||
|
|
/**
|
||
|
|
* Converts a Promise to an Observable.
|
||
|
|
*
|
||
|
|
* <span class="informal">Returns an Observable that just emits the Promise's
|
||
|
|
* resolved value, then completes.</span>
|
||
|
|
*
|
||
|
|
* Converts an ES2015 Promise or a Promises/A+ spec compliant Promise to an
|
||
|
|
* Observable. If the Promise resolves with a value, the output Observable
|
||
|
|
* emits that resolved value as a `next`, and then completes. If the Promise
|
||
|
|
* is rejected, then the output Observable emits the corresponding Error.
|
||
|
|
*
|
||
|
|
* @example <caption>Convert the Promise returned by Fetch to an Observable</caption>
|
||
|
|
* var result = Rx.Observable.fromPromise(fetch('http://myserver.com/'));
|
||
|
|
* result.subscribe(x => console.log(x), e => console.error(e));
|
||
|
|
*
|
||
|
|
* @see {@link bindCallback}
|
||
|
|
* @see {@link from}
|
||
|
|
*
|
||
|
|
* @param {PromiseLike<T>} promise The promise to be converted.
|
||
|
|
* @param {Scheduler} [scheduler] An optional IScheduler to use for scheduling
|
||
|
|
* the delivery of the resolved value (or the rejection).
|
||
|
|
* @return {Observable<T>} An Observable which wraps the Promise.
|
||
|
|
* @static true
|
||
|
|
* @name fromPromise
|
||
|
|
* @owner Observable
|
||
|
|
*/
|
||
|
|
static create(promise, scheduler) {
|
||
|
|
return new PromiseObservable(promise, scheduler);
|
||
|
|
}
|
||
|
|
/** @deprecated internal use only */ _subscribe(subscriber) {
|
||
|
|
const promise = this.promise;
|
||
|
|
const scheduler = this.scheduler;
|
||
|
|
if (scheduler == null) {
|
||
|
|
if (this._isScalar) {
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
subscriber.next(this.value);
|
||
|
|
subscriber.complete();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
promise.then((value) => {
|
||
|
|
this.value = value;
|
||
|
|
this._isScalar = true;
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
subscriber.next(value);
|
||
|
|
subscriber.complete();
|
||
|
|
}
|
||
|
|
}, (err) => {
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
subscriber.error(err);
|
||
|
|
}
|
||
|
|
})
|
||
|
|
.then(null, err => {
|
||
|
|
// escape the promise trap, throw unhandled errors
|
||
|
|
root.setTimeout(() => { throw err; });
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
if (this._isScalar) {
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
return scheduler.schedule(dispatchNext, 0, { value: this.value, subscriber });
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
promise.then((value) => {
|
||
|
|
this.value = value;
|
||
|
|
this._isScalar = true;
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
subscriber.add(scheduler.schedule(dispatchNext, 0, { value, subscriber }));
|
||
|
|
}
|
||
|
|
}, (err) => {
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
subscriber.add(scheduler.schedule(dispatchError, 0, { err, subscriber }));
|
||
|
|
}
|
||
|
|
})
|
||
|
|
.then(null, (err) => {
|
||
|
|
// escape the promise trap, throw unhandled errors
|
||
|
|
root.setTimeout(() => { throw err; });
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
function dispatchNext(arg) {
|
||
|
|
const { value, subscriber } = arg;
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
subscriber.next(value);
|
||
|
|
subscriber.complete();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
function dispatchError(arg) {
|
||
|
|
const { err, subscriber } = arg;
|
||
|
|
if (!subscriber.closed) {
|
||
|
|
subscriber.error(err);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
//# sourceMappingURL=PromiseObservable.js.map
|