190 lines
7.3 KiB
JavaScript
190 lines
7.3 KiB
JavaScript
import { async } from '../scheduler/async';
|
|
import { Subscriber } from '../Subscriber';
|
|
import { isScheduler } from '../util/isScheduler';
|
|
/* tslint:enable:max-line-length */
|
|
/**
|
|
* Buffers the source Observable values for a specific time period.
|
|
*
|
|
* <span class="informal">Collects values from the past as an array, and emits
|
|
* those arrays periodically in time.</span>
|
|
*
|
|
* <img src="./img/bufferTime.png" width="100%">
|
|
*
|
|
* Buffers values from the source for a specific time duration `bufferTimeSpan`.
|
|
* Unless the optional argument `bufferCreationInterval` is given, it emits and
|
|
* resets the buffer every `bufferTimeSpan` milliseconds. If
|
|
* `bufferCreationInterval` is given, this operator opens the buffer every
|
|
* `bufferCreationInterval` milliseconds and closes (emits and resets) the
|
|
* buffer every `bufferTimeSpan` milliseconds. When the optional argument
|
|
* `maxBufferSize` is specified, the buffer will be closed either after
|
|
* `bufferTimeSpan` milliseconds or when it contains `maxBufferSize` elements.
|
|
*
|
|
* @example <caption>Every second, emit an array of the recent click events</caption>
|
|
* var clicks = Rx.Observable.fromEvent(document, 'click');
|
|
* var buffered = clicks.bufferTime(1000);
|
|
* buffered.subscribe(x => console.log(x));
|
|
*
|
|
* @example <caption>Every 5 seconds, emit the click events from the next 2 seconds</caption>
|
|
* var clicks = Rx.Observable.fromEvent(document, 'click');
|
|
* var buffered = clicks.bufferTime(2000, 5000);
|
|
* buffered.subscribe(x => console.log(x));
|
|
*
|
|
* @see {@link buffer}
|
|
* @see {@link bufferCount}
|
|
* @see {@link bufferToggle}
|
|
* @see {@link bufferWhen}
|
|
* @see {@link windowTime}
|
|
*
|
|
* @param {number} bufferTimeSpan The amount of time to fill each buffer array.
|
|
* @param {number} [bufferCreationInterval] The interval at which to start new
|
|
* buffers.
|
|
* @param {number} [maxBufferSize] The maximum buffer size.
|
|
* @param {Scheduler} [scheduler=async] The scheduler on which to schedule the
|
|
* intervals that determine buffer boundaries.
|
|
* @return {Observable<T[]>} An observable of arrays of buffered values.
|
|
* @method bufferTime
|
|
* @owner Observable
|
|
*/
|
|
export function bufferTime(bufferTimeSpan) {
|
|
let length = arguments.length;
|
|
let scheduler = async;
|
|
if (isScheduler(arguments[arguments.length - 1])) {
|
|
scheduler = arguments[arguments.length - 1];
|
|
length--;
|
|
}
|
|
let bufferCreationInterval = null;
|
|
if (length >= 2) {
|
|
bufferCreationInterval = arguments[1];
|
|
}
|
|
let maxBufferSize = Number.POSITIVE_INFINITY;
|
|
if (length >= 3) {
|
|
maxBufferSize = arguments[2];
|
|
}
|
|
return function bufferTimeOperatorFunction(source) {
|
|
return source.lift(new BufferTimeOperator(bufferTimeSpan, bufferCreationInterval, maxBufferSize, scheduler));
|
|
};
|
|
}
|
|
class BufferTimeOperator {
|
|
constructor(bufferTimeSpan, bufferCreationInterval, maxBufferSize, scheduler) {
|
|
this.bufferTimeSpan = bufferTimeSpan;
|
|
this.bufferCreationInterval = bufferCreationInterval;
|
|
this.maxBufferSize = maxBufferSize;
|
|
this.scheduler = scheduler;
|
|
}
|
|
call(subscriber, source) {
|
|
return source.subscribe(new BufferTimeSubscriber(subscriber, this.bufferTimeSpan, this.bufferCreationInterval, this.maxBufferSize, this.scheduler));
|
|
}
|
|
}
|
|
class Context {
|
|
constructor() {
|
|
this.buffer = [];
|
|
}
|
|
}
|
|
/**
|
|
* We need this JSDoc comment for affecting ESDoc.
|
|
* @ignore
|
|
* @extends {Ignored}
|
|
*/
|
|
class BufferTimeSubscriber extends Subscriber {
|
|
constructor(destination, bufferTimeSpan, bufferCreationInterval, maxBufferSize, scheduler) {
|
|
super(destination);
|
|
this.bufferTimeSpan = bufferTimeSpan;
|
|
this.bufferCreationInterval = bufferCreationInterval;
|
|
this.maxBufferSize = maxBufferSize;
|
|
this.scheduler = scheduler;
|
|
this.contexts = [];
|
|
const context = this.openContext();
|
|
this.timespanOnly = bufferCreationInterval == null || bufferCreationInterval < 0;
|
|
if (this.timespanOnly) {
|
|
const timeSpanOnlyState = { subscriber: this, context, bufferTimeSpan };
|
|
this.add(context.closeAction = scheduler.schedule(dispatchBufferTimeSpanOnly, bufferTimeSpan, timeSpanOnlyState));
|
|
}
|
|
else {
|
|
const closeState = { subscriber: this, context };
|
|
const creationState = { bufferTimeSpan, bufferCreationInterval, subscriber: this, scheduler };
|
|
this.add(context.closeAction = scheduler.schedule(dispatchBufferClose, bufferTimeSpan, closeState));
|
|
this.add(scheduler.schedule(dispatchBufferCreation, bufferCreationInterval, creationState));
|
|
}
|
|
}
|
|
_next(value) {
|
|
const contexts = this.contexts;
|
|
const len = contexts.length;
|
|
let filledBufferContext;
|
|
for (let i = 0; i < len; i++) {
|
|
const context = contexts[i];
|
|
const buffer = context.buffer;
|
|
buffer.push(value);
|
|
if (buffer.length == this.maxBufferSize) {
|
|
filledBufferContext = context;
|
|
}
|
|
}
|
|
if (filledBufferContext) {
|
|
this.onBufferFull(filledBufferContext);
|
|
}
|
|
}
|
|
_error(err) {
|
|
this.contexts.length = 0;
|
|
super._error(err);
|
|
}
|
|
_complete() {
|
|
const { contexts, destination } = this;
|
|
while (contexts.length > 0) {
|
|
const context = contexts.shift();
|
|
destination.next(context.buffer);
|
|
}
|
|
super._complete();
|
|
}
|
|
/** @deprecated internal use only */ _unsubscribe() {
|
|
this.contexts = null;
|
|
}
|
|
onBufferFull(context) {
|
|
this.closeContext(context);
|
|
const closeAction = context.closeAction;
|
|
closeAction.unsubscribe();
|
|
this.remove(closeAction);
|
|
if (!this.closed && this.timespanOnly) {
|
|
context = this.openContext();
|
|
const bufferTimeSpan = this.bufferTimeSpan;
|
|
const timeSpanOnlyState = { subscriber: this, context, bufferTimeSpan };
|
|
this.add(context.closeAction = this.scheduler.schedule(dispatchBufferTimeSpanOnly, bufferTimeSpan, timeSpanOnlyState));
|
|
}
|
|
}
|
|
openContext() {
|
|
const context = new Context();
|
|
this.contexts.push(context);
|
|
return context;
|
|
}
|
|
closeContext(context) {
|
|
this.destination.next(context.buffer);
|
|
const contexts = this.contexts;
|
|
const spliceIndex = contexts ? contexts.indexOf(context) : -1;
|
|
if (spliceIndex >= 0) {
|
|
contexts.splice(contexts.indexOf(context), 1);
|
|
}
|
|
}
|
|
}
|
|
function dispatchBufferTimeSpanOnly(state) {
|
|
const subscriber = state.subscriber;
|
|
const prevContext = state.context;
|
|
if (prevContext) {
|
|
subscriber.closeContext(prevContext);
|
|
}
|
|
if (!subscriber.closed) {
|
|
state.context = subscriber.openContext();
|
|
state.context.closeAction = this.schedule(state, state.bufferTimeSpan);
|
|
}
|
|
}
|
|
function dispatchBufferCreation(state) {
|
|
const { bufferCreationInterval, bufferTimeSpan, subscriber, scheduler } = state;
|
|
const context = subscriber.openContext();
|
|
const action = this;
|
|
if (!subscriber.closed) {
|
|
subscriber.add(context.closeAction = scheduler.schedule(dispatchBufferClose, bufferTimeSpan, { subscriber, context }));
|
|
action.schedule(state, bufferCreationInterval);
|
|
}
|
|
}
|
|
function dispatchBufferClose(arg) {
|
|
const { subscriber, context } = arg;
|
|
subscriber.closeContext(context);
|
|
}
|
|
//# sourceMappingURL=bufferTime.js.map
|