You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
156 lines
5.3 KiB
156 lines
5.3 KiB
'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']; |