'use strict'; Object.defineProperty(exports, "__esModule", { value: true }); exports.default = retry; var _noop = require('lodash/noop'); var _noop2 = _interopRequireDefault(_noop); var _constant = require('lodash/constant'); var _constant2 = _interopRequireDefault(_constant); var _wrapAsync = require('./internal/wrapAsync'); var _wrapAsync2 = _interopRequireDefault(_wrapAsync); function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; } /** * Attempts to get a successful response from `task` no more than `times` times * before returning an error. If the task is successful, the `callback` will be * passed the result of the successful task. If all attempts fail, the callback * will be passed the error and result (if any) of the final attempt. * * @name retry * @static * @memberOf module:ControlFlow * @method * @category Control Flow * @see [async.retryable]{@link module:ControlFlow.retryable} * @param {Object|number} [opts = {times: 5, interval: 0}| 5] - Can be either an * object with `times` and `interval` or a number. * * `times` - The number of attempts to make before giving up. The default * is `5`. * * `interval` - The time to wait between retries, in milliseconds. The * default is `0`. The interval may also be specified as a function of the * retry count (see example). * * `errorFilter` - An optional synchronous function that is invoked on * erroneous result. If it returns `true` the retry attempts will continue; * if the function returns `false` the retry flow is aborted with the current * attempt's error and result being returned to the final callback. * Invoked with (err). * * If `opts` is a number, the number specifies the number of times to retry, * with the default interval of `0`. * @param {AsyncFunction} task - An async function to retry. * Invoked with (callback). * @param {Function} [callback] - An optional callback which is called when the * task has succeeded, or after the final failed attempt. It receives the `err` * and `result` arguments of the last attempt at completing the `task`. Invoked * with (err, results). * * @example * * // The `retry` function can be used as a stand-alone control flow by passing * // a callback, as shown below: * * // try calling apiMethod 3 times * async.retry(3, apiMethod, function(err, result) { * // do something with the result * }); * * // try calling apiMethod 3 times, waiting 200 ms between each retry * async.retry({times: 3, interval: 200}, apiMethod, function(err, result) { * // do something with the result * }); * * // try calling apiMethod 10 times with exponential backoff * // (i.e. intervals of 100, 200, 400, 800, 1600, ... milliseconds) * async.retry({ * times: 10, * interval: function(retryCount) { * return 50 * Math.pow(2, retryCount); * } * }, apiMethod, function(err, result) { * // do something with the result * }); * * // try calling apiMethod the default 5 times no delay between each retry * async.retry(apiMethod, function(err, result) { * // do something with the result * }); * * // try calling apiMethod only when error condition satisfies, all other * // errors will abort the retry control flow and return to final callback * async.retry({ * errorFilter: function(err) { * return err.message === 'Temporary error'; // only retry on a specific error * } * }, apiMethod, function(err, result) { * // do something with the result * }); * * // to retry individual methods that are not as reliable within other * // control flow functions, use the `retryable` wrapper: * async.auto({ * users: api.getUsers.bind(api), * payments: async.retryable(3, api.getPayments.bind(api)) * }, function(err, results) { * // do something with the results * }); * */ function retry(opts, task, callback) { var DEFAULT_TIMES = 5; var DEFAULT_INTERVAL = 0; var options = { times: DEFAULT_TIMES, intervalFunc: (0, _constant2.default)(DEFAULT_INTERVAL) }; function parseTimes(acc, t) { if (typeof t === 'object') { acc.times = +t.times || DEFAULT_TIMES; acc.intervalFunc = typeof t.interval === 'function' ? t.interval : (0, _constant2.default)(+t.interval || DEFAULT_INTERVAL); acc.errorFilter = t.errorFilter; } else if (typeof t === 'number' || typeof t === 'string') { acc.times = +t || DEFAULT_TIMES; } else { throw new Error("Invalid arguments for async.retry"); } } if (arguments.length < 3 && typeof opts === 'function') { callback = task || _noop2.default; task = opts; } else { parseTimes(options, opts); callback = callback || _noop2.default; } if (typeof task !== 'function') { throw new Error("Invalid arguments for async.retry"); } var _task = (0, _wrapAsync2.default)(task); var attempt = 1; function retryAttempt() { _task(function (err) { if (err && attempt++ < options.times && (typeof options.errorFilter != 'function' || options.errorFilter(err))) { setTimeout(retryAttempt, options.intervalFunc(attempt)); } else { callback.apply(null, arguments); } }); } retryAttempt(); } module.exports = exports['default'];