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- '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'];
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