| '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']; |