--- /dev/null
+'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);
+
+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
+ * @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 {Function} task - A function which receives two arguments: (1) a
+ * `callback(err, result)` which must be called when finished, passing `err`
+ * (which can be `null`) and the `result` of the function's execution, and (2)
+ * a `results` object, containing the results of the previously executed
+ * functions (if nested inside another control flow). Invoked with
+ * (callback, results).
+ * @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
+ * });
+ *
+ * // It can also be embedded within other control flow functions to retry
+ * // individual methods that are not as reliable, like this:
+ * async.auto({
+ * users: api.getUsers.bind(api),
+ * payments: async.retry(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 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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projects / yaffs-website / blobdiff