promise-util-task/dist/lib/task.js

task manager for promise

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
/**
 * It will always be executed in the order waiting for the result of Promise.
 * @param funcs An array of functions that return value, or promise.
 * @returns Results are stored in the order stored in funcs.
 */
exports.seq = function (funcs) {
    var results = [];
    return funcs.reduce(function (prevPromise, func) {
        return prevPromise.then(function () {
            return Promise.resolve(func()).then(function (value) {
                results.push(value);
            });
        });
    }, Promise.resolve()).then(function () { return results; });
};
/**
 * Execute processing at once.
 * @param funcs An array of functions that return value, or promise.
 * @returns Results are stored in the order stored in funcs.
 */
exports.all = function (funcs) {
    var promises = funcs.map(function (func) {
        try {
            return Promise.resolve(func());
        }
        catch (e) {
            return Promise.reject(e);
        }
    });
    return Promise.all(promises);
};
/**
 * Execute the specified number of processes at once.
 * @param funcs An array of functions that return value, or promise.
 * @param max Maximum number of simultaneous executions.
 * @returns Results are stored in the order stored in funcs.
 */
exports.limit = function (funcs, max) {
    if (max === void 0) { max = 1; }
    return exports.all(limit_preprocess(funcs, max)).
        then(limit_postprocess);
};
var limit_preprocess = function (funcs, max) {
    var pipeline = [];
    for (var i = 0; i < max; ++i) {
        pipeline[i] = [];
    }
    funcs.forEach(function (func, n) {
        var idx = n % max;
        pipeline[idx].push(func);
    });
    return pipeline.map(function (funcs) {
        return function () { return exports.seq(funcs); };
    });
};
var limit_postprocess = function (matrix) {
    var max = matrix.reduce(function (sum, line) { return sum + line.length; }, 0);
    var results = new Array(max);
    var len = matrix.length;
    for (var i = 0; i < len; ++i) {
        var lenj = matrix[i].length;
        for (var j = 0; j < lenj; ++j) {
            results[i + (j * len)] = matrix[i][j];
        }
    }
    return results;
};