1'use strict'; 2 3Object.defineProperty(exports, "__esModule", { 4 value: true 5}); 6 7var _eachSeries = require('./eachSeries.js'); 8 9var _eachSeries2 = _interopRequireDefault(_eachSeries); 10 11var _wrapAsync = require('./internal/wrapAsync.js'); 12 13var _wrapAsync2 = _interopRequireDefault(_wrapAsync); 14 15var _awaitify = require('./internal/awaitify.js'); 16 17var _awaitify2 = _interopRequireDefault(_awaitify); 18 19function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; } 20 21/** 22 * It runs each task in series but stops whenever any of the functions were 23 * successful. If one of the tasks were successful, the `callback` will be 24 * passed the result of the successful task. If all tasks fail, the callback 25 * will be passed the error and result (if any) of the final attempt. 26 * 27 * @name tryEach 28 * @static 29 * @memberOf module:ControlFlow 30 * @method 31 * @category Control Flow 32 * @param {Array|Iterable|AsyncIterable|Object} tasks - A collection containing functions to 33 * run, each function is passed a `callback(err, result)` it must call on 34 * completion with an error `err` (which can be `null`) and an optional `result` 35 * value. 36 * @param {Function} [callback] - An optional callback which is called when one 37 * of the tasks has succeeded, or all have failed. It receives the `err` and 38 * `result` arguments of the last attempt at completing the `task`. Invoked with 39 * (err, results). 40 * @returns {Promise} a promise, if no callback is passed 41 * @example 42 * async.tryEach([ 43 * function getDataFromFirstWebsite(callback) { 44 * // Try getting the data from the first website 45 * callback(err, data); 46 * }, 47 * function getDataFromSecondWebsite(callback) { 48 * // First website failed, 49 * // Try getting the data from the backup website 50 * callback(err, data); 51 * } 52 * ], 53 * // optional callback 54 * function(err, results) { 55 * Now do something with the data. 56 * }); 57 * 58 */ 59function tryEach(tasks, callback) { 60 var error = null; 61 var result; 62 return (0, _eachSeries2.default)(tasks, (task, taskCb) => { 63 (0, _wrapAsync2.default)(task)((err, ...args) => { 64 if (err === false) return taskCb(err); 65 66 if (args.length < 2) { 67 [result] = args; 68 } else { 69 result = args; 70 } 71 error = err; 72 taskCb(err ? null : {}); 73 }); 74 }, () => callback(error, result)); 75} 76 77exports.default = (0, _awaitify2.default)(tryEach); 78module.exports = exports['default'];