util-helpers/lib/ConcurrencyController.js

一个基于业务场景的工具方法库

'use strict';

var ConcurrencyController = (function () {
    function ConcurrencyController(maxConcurrency) {
        if (maxConcurrency === void 0) { maxConcurrency = 2; }
        this.maxConcurrency = Math.max(maxConcurrency, 1);
        this.runningCount = 0;
        this.queue = [];
        this.isPaused = false;
    }
    ConcurrencyController.prototype.add = function (task) {
        var _this = this;
        return new Promise(function (resolve, reject) {
            _this.queue.push({ task: task, resolve: resolve, reject: reject });
            _this._run();
        });
    };
    ConcurrencyController.prototype._run = function () {
        var _this = this;
        if (this.isPaused)
            return;
        while (this.runningCount < this.maxConcurrency && this.queue.length > 0) {
            var _a = this.queue.shift(), task = _a.task, resolve = _a.resolve, reject = _a.reject;
            this.runningCount++;
            task()
                .then(resolve)
                .catch(reject)
                .finally(function () {
                _this.runningCount--;
                _this._run();
            });
        }
    };
    ConcurrencyController.prototype.getStatus = function () {
        return {
            running: this.runningCount,
            waiting: this.queue.length,
            maxConcurrency: this.maxConcurrency,
            paused: this.isPaused
        };
    };
    ConcurrencyController.prototype.setMaxConcurrency = function (maxConcurrency) {
        this.maxConcurrency = Math.max(maxConcurrency, 1);
        this._run();
    };
    ConcurrencyController.prototype.pause = function () {
        this.isPaused = true;
    };
    ConcurrencyController.prototype.resume = function () {
        this.isPaused = false;
        this._run();
    };
    return ConcurrencyController;
}());

module.exports = ConcurrencyController;