123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142 |
- "use strict";
- var __extends = (this && this.__extends) || function (d, b) {
- for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
- function __() { this.constructor = d; }
- d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
- };
- var root_1 = require('../util/root');
- var Action_1 = require('./Action');
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
- var AsyncAction = (function (_super) {
- __extends(AsyncAction, _super);
- function AsyncAction(scheduler, work) {
- _super.call(this, scheduler, work);
- this.scheduler = scheduler;
- this.work = work;
- this.pending = false;
- }
- AsyncAction.prototype.schedule = function (state, delay) {
- if (delay === void 0) { delay = 0; }
- if (this.closed) {
- return this;
- }
- // Always replace the current state with the new state.
- this.state = state;
- // Set the pending flag indicating that this action has been scheduled, or
- // has recursively rescheduled itself.
- this.pending = true;
- var id = this.id;
- var scheduler = this.scheduler;
- //
- // Important implementation note:
- //
- // Actions only execute once by default, unless rescheduled from within the
- // scheduled callback. This allows us to implement single and repeat
- // actions via the same code path, without adding API surface area, as well
- // as mimic traditional recursion but across asynchronous boundaries.
- //
- // However, JS runtimes and timers distinguish between intervals achieved by
- // serial `setTimeout` calls vs. a single `setInterval` call. An interval of
- // serial `setTimeout` calls can be individually delayed, which delays
- // scheduling the next `setTimeout`, and so on. `setInterval` attempts to
- // guarantee the interval callback will be invoked more precisely to the
- // interval period, regardless of load.
- //
- // Therefore, we use `setInterval` to schedule single and repeat actions.
- // If the action reschedules itself with the same delay, the interval is not
- // canceled. If the action doesn't reschedule, or reschedules with a
- // different delay, the interval will be canceled after scheduled callback
- // execution.
- //
- if (id != null) {
- this.id = this.recycleAsyncId(scheduler, id, delay);
- }
- this.delay = delay;
- // If this action has already an async Id, don't request a new one.
- this.id = this.id || this.requestAsyncId(scheduler, this.id, delay);
- return this;
- };
- AsyncAction.prototype.requestAsyncId = function (scheduler, id, delay) {
- if (delay === void 0) { delay = 0; }
- return root_1.root.setInterval(scheduler.flush.bind(scheduler, this), delay);
- };
- AsyncAction.prototype.recycleAsyncId = function (scheduler, id, delay) {
- if (delay === void 0) { delay = 0; }
- // If this action is rescheduled with the same delay time, don't clear the interval id.
- if (delay !== null && this.delay === delay && this.pending === false) {
- return id;
- }
- // Otherwise, if the action's delay time is different from the current delay,
- // or the action has been rescheduled before it's executed, clear the interval id
- return root_1.root.clearInterval(id) && undefined || undefined;
- };
- /**
- * Immediately executes this action and the `work` it contains.
- * @return {any}
- */
- AsyncAction.prototype.execute = function (state, delay) {
- if (this.closed) {
- return new Error('executing a cancelled action');
- }
- this.pending = false;
- var error = this._execute(state, delay);
- if (error) {
- return error;
- }
- else if (this.pending === false && this.id != null) {
- // Dequeue if the action didn't reschedule itself. Don't call
- // unsubscribe(), because the action could reschedule later.
- // For example:
- // ```
- // scheduler.schedule(function doWork(counter) {
- // /* ... I'm a busy worker bee ... */
- // var originalAction = this;
- // /* wait 100ms before rescheduling the action */
- // setTimeout(function () {
- // originalAction.schedule(counter + 1);
- // }, 100);
- // }, 1000);
- // ```
- this.id = this.recycleAsyncId(this.scheduler, this.id, null);
- }
- };
- AsyncAction.prototype._execute = function (state, delay) {
- var errored = false;
- var errorValue = undefined;
- try {
- this.work(state);
- }
- catch (e) {
- errored = true;
- errorValue = !!e && e || new Error(e);
- }
- if (errored) {
- this.unsubscribe();
- return errorValue;
- }
- };
- /** @deprecated internal use only */ AsyncAction.prototype._unsubscribe = function () {
- var id = this.id;
- var scheduler = this.scheduler;
- var actions = scheduler.actions;
- var index = actions.indexOf(this);
- this.work = null;
- this.state = null;
- this.pending = false;
- this.scheduler = null;
- if (index !== -1) {
- actions.splice(index, 1);
- }
- if (id != null) {
- this.id = this.recycleAsyncId(scheduler, id, null);
- }
- this.delay = null;
- };
- return AsyncAction;
- }(Action_1.Action));
- exports.AsyncAction = AsyncAction;
- //# sourceMappingURL=AsyncAction.js.map
|