p-queue-es5
Version:
Promise queue with concurrency control
372 lines (369 loc) • 16.1 kB
JavaScript
"use strict";
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
var __assign = (this && this.__assign) || function () {
__assign = Object.assign || function(t) {
for (var s, i = 1, n = arguments.length; i < n; i++) {
s = arguments[i];
for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
t[p] = s[p];
}
return t;
};
return __assign.apply(this, arguments);
};
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
Object.defineProperty(exports, "__esModule", { value: true });
var EventEmitter = require("eventemitter3");
var p_timeout_1 = require("p-timeout");
var priority_queue_1 = require("./priority-queue");
var empty = function () { };
var timeoutError = new p_timeout_1.default.TimeoutError();
/**
Promise queue with concurrency control.
*/
var PQueue = /** @class */ (function (_super) {
__extends(PQueue, _super);
function PQueue(options) {
var _this = _super.call(this) || this;
_this._intervalCount = 0;
_this._intervalEnd = 0;
_this._pendingCount = 0;
_this._resolveEmpty = empty;
_this._resolveIdle = empty;
// eslint-disable-next-line @typescript-eslint/no-object-literal-type-assertion
options = __assign({ carryoverConcurrencyCount: false, intervalCap: Infinity, interval: 0, concurrency: Infinity, autoStart: true, queueClass: priority_queue_1.default }, options);
if (!(typeof options.concurrency === 'number' && options.concurrency >= 1)) {
throw new TypeError("Expected `concurrency` to be a number from 1 and up, got `" + options.concurrency + "` (" + typeof options.concurrency + ")");
}
if (!(typeof options.intervalCap === 'number' && options.intervalCap >= 1)) {
throw new TypeError("Expected `intervalCap` to be a number from 1 and up, got `" + options.intervalCap + "` (" + typeof options.intervalCap + ")");
}
if (options.interval === undefined || !(Number.isFinite(options.interval) && options.interval >= 0)) {
throw new TypeError("Expected `interval` to be a finite number >= 0, got `" + options.interval + "` (" + typeof options.interval + ")");
}
_this._carryoverConcurrencyCount = options.carryoverConcurrencyCount;
_this._isIntervalIgnored = options.intervalCap === Infinity || options.interval === 0;
_this._intervalCap = options.intervalCap;
_this._interval = options.interval;
_this._queue = new options.queueClass();
_this._queueClass = options.queueClass;
_this._concurrency = options.concurrency;
_this._timeout = options.timeout;
_this._throwOnTimeout = options.throwOnTimeout === true;
_this._paused = options.autoStart === false;
return _this;
}
Object.defineProperty(PQueue.prototype, "doesIntervalAllowAnother", {
get: function () {
return this._isIntervalIgnored || this._intervalCount < this._intervalCap;
},
enumerable: true,
configurable: true
});
Object.defineProperty(PQueue.prototype, "doesConcurrentAllowAnother", {
get: function () {
return this._pendingCount < this._concurrency;
},
enumerable: true,
configurable: true
});
PQueue.prototype.next = function () {
this._pendingCount--;
this.tryToStartAnother();
};
PQueue.prototype.resolvePromises = function () {
this._resolveEmpty();
this._resolveEmpty = empty;
if (this._pendingCount === 0) {
this._resolveIdle();
this._resolveIdle = empty;
}
};
PQueue.prototype.onResumeInterval = function () {
this.onInterval();
this.initializeIntervalIfNeeded();
this._timeoutId = undefined;
};
PQueue.prototype.intervalPaused = function () {
var _this = this;
var now = Date.now();
if (this._intervalId === undefined) {
var delay = this._intervalEnd - now;
if (delay < 0) {
// Act as the interval was done
// We don't need to resume it here because it will be resumed on line 160
this._intervalCount = (this._carryoverConcurrencyCount) ? this._pendingCount : 0;
}
else {
// Act as the interval is pending
if (this._timeoutId === undefined) {
this._timeoutId = setTimeout(function () {
_this.onResumeInterval();
}, delay);
}
return true;
}
}
return false;
};
PQueue.prototype.tryToStartAnother = function () {
if (this._queue.size === 0) {
// We can clear the interval ("pause")
// Because we can redo it later ("resume")
if (this._intervalId) {
clearInterval(this._intervalId);
}
this._intervalId = undefined;
this.resolvePromises();
return false;
}
if (!this._paused) {
var canInitializeInterval = !this.intervalPaused();
if (this.doesIntervalAllowAnother && this.doesConcurrentAllowAnother) {
this.emit('active');
this._queue.dequeue()();
if (canInitializeInterval) {
this.initializeIntervalIfNeeded();
}
return true;
}
}
return false;
};
PQueue.prototype.initializeIntervalIfNeeded = function () {
var _this = this;
if (this._isIntervalIgnored || this._intervalId !== undefined) {
return;
}
this._intervalId = setInterval(function () {
_this.onInterval();
}, this._interval);
this._intervalEnd = Date.now() + this._interval;
};
PQueue.prototype.onInterval = function () {
if (this._intervalCount === 0 && this._pendingCount === 0 && this._intervalId) {
clearInterval(this._intervalId);
this._intervalId = undefined;
}
this._intervalCount = this._carryoverConcurrencyCount ? this._pendingCount : 0;
// eslint-disable-next-line no-empty
while (this.tryToStartAnother()) { }
};
/**
Adds a sync or async task to the queue. Always returns a promise.
*/
PQueue.prototype.add = function (fn, options) {
return __awaiter(this, void 0, void 0, function () {
var _this = this;
return __generator(this, function (_a) {
return [2 /*return*/, new Promise(function (resolve, reject) {
var run = function () { return __awaiter(_this, void 0, void 0, function () {
var operation, _a, error_1;
var _this = this;
return __generator(this, function (_b) {
switch (_b.label) {
case 0:
this._pendingCount++;
this._intervalCount++;
_b.label = 1;
case 1:
_b.trys.push([1, 3, , 4]);
operation = this._timeout === undefined ? fn() : p_timeout_1.default(Promise.resolve(fn()), this._timeout, function () {
if (_this._throwOnTimeout) {
reject(timeoutError);
}
return undefined;
});
_a = resolve;
return [4 /*yield*/, operation];
case 2:
_a.apply(void 0, [_b.sent()]);
return [3 /*break*/, 4];
case 3:
error_1 = _b.sent();
reject(error_1);
return [3 /*break*/, 4];
case 4:
this.next();
return [2 /*return*/];
}
});
}); };
_this._queue.enqueue(run, options);
_this.tryToStartAnother();
})];
});
});
};
/**
Same as `.add()`, but accepts an array of sync or async functions.
@returns A promise that resolves when all functions are resolved.
*/
PQueue.prototype.addAll = function (functions, options) {
return __awaiter(this, void 0, void 0, function () {
var _this = this;
return __generator(this, function (_a) {
return [2 /*return*/, Promise.all(functions.map(function (function_) { return _this.add(function_, options); }))];
});
});
};
/**
Start (or resume) executing enqueued tasks within concurrency limit. No need to call this if queue is not paused (via `options.autoStart = false` or by `.pause()` method.)
*/
PQueue.prototype.start = function () {
if (!this._paused) {
return;
}
this._paused = false;
// eslint-disable-next-line no-empty
while (this.tryToStartAnother()) { }
};
/**
Put queue execution on hold.
*/
PQueue.prototype.pause = function () {
this._paused = true;
};
/**
Clear the queue.
*/
PQueue.prototype.clear = function () {
this._queue = new this._queueClass();
};
/**
Can be called multiple times. Useful if you for example add additional items at a later time.
@returns A promise that settles when the queue becomes empty.
*/
PQueue.prototype.onEmpty = function () {
return __awaiter(this, void 0, void 0, function () {
var _this = this;
return __generator(this, function (_a) {
// Instantly resolve if the queue is empty
if (this._queue.size === 0) {
return [2 /*return*/];
}
return [2 /*return*/, new Promise(function (resolve) {
var existingResolve = _this._resolveEmpty;
_this._resolveEmpty = function () {
existingResolve();
resolve();
};
})];
});
});
};
/**
The difference with `.onEmpty` is that `.onIdle` guarantees that all work from the queue has finished. `.onEmpty` merely signals that the queue is empty, but it could mean that some promises haven't completed yet.
@returns A promise that settles when the queue becomes empty, and all promises have completed; `queue.size === 0 && queue.pending === 0`.
*/
PQueue.prototype.onIdle = function () {
return __awaiter(this, void 0, void 0, function () {
var _this = this;
return __generator(this, function (_a) {
// Instantly resolve if none pending and if nothing else is queued
if (this._pendingCount === 0 && this._queue.size === 0) {
return [2 /*return*/];
}
return [2 /*return*/, new Promise(function (resolve) {
var existingResolve = _this._resolveIdle;
_this._resolveIdle = function () {
existingResolve();
resolve();
};
})];
});
});
};
Object.defineProperty(PQueue.prototype, "size", {
/**
Size of the queue.
*/
get: function () {
return this._queue.size;
},
enumerable: true,
configurable: true
});
Object.defineProperty(PQueue.prototype, "pending", {
/**
Number of pending promises.
*/
get: function () {
return this._pendingCount;
},
enumerable: true,
configurable: true
});
Object.defineProperty(PQueue.prototype, "isPaused", {
/**
Whether the queue is currently paused.
*/
get: function () {
return this._paused;
},
enumerable: true,
configurable: true
});
Object.defineProperty(PQueue.prototype, "timeout", {
get: function () {
return this._timeout;
},
/**
Set the timeout for future operations.
*/
set: function (milliseconds) {
this._timeout = milliseconds;
},
enumerable: true,
configurable: true
});
return PQueue;
}(EventEmitter));
exports.default = PQueue;
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