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.
130 lines
5.7 KiB
130 lines
5.7 KiB
'use strict'; |
|
|
|
Object.defineProperty(exports, "__esModule", { |
|
value: true |
|
}); |
|
|
|
exports.default = function (worker, concurrency) { |
|
var _worker = (0, _wrapAsync2.default)(worker); |
|
return (0, _queue2.default)(function (items, cb) { |
|
_worker(items[0], cb); |
|
}, concurrency, 1); |
|
}; |
|
|
|
var _queue = require('./internal/queue'); |
|
|
|
var _queue2 = _interopRequireDefault(_queue); |
|
|
|
var _wrapAsync = require('./internal/wrapAsync'); |
|
|
|
var _wrapAsync2 = _interopRequireDefault(_wrapAsync); |
|
|
|
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; } |
|
|
|
module.exports = exports['default']; |
|
|
|
/** |
|
* A queue of tasks for the worker function to complete. |
|
* @typedef {Object} QueueObject |
|
* @memberOf module:ControlFlow |
|
* @property {Function} length - a function returning the number of items |
|
* waiting to be processed. Invoke with `queue.length()`. |
|
* @property {boolean} started - a boolean indicating whether or not any |
|
* items have been pushed and processed by the queue. |
|
* @property {Function} running - a function returning the number of items |
|
* currently being processed. Invoke with `queue.running()`. |
|
* @property {Function} workersList - a function returning the array of items |
|
* currently being processed. Invoke with `queue.workersList()`. |
|
* @property {Function} idle - a function returning false if there are items |
|
* waiting or being processed, or true if not. Invoke with `queue.idle()`. |
|
* @property {number} concurrency - an integer for determining how many `worker` |
|
* functions should be run in parallel. This property can be changed after a |
|
* `queue` is created to alter the concurrency on-the-fly. |
|
* @property {Function} push - add a new task to the `queue`. Calls `callback` |
|
* once the `worker` has finished processing the task. Instead of a single task, |
|
* a `tasks` array can be submitted. The respective callback is used for every |
|
* task in the list. Invoke with `queue.push(task, [callback])`, |
|
* @property {Function} unshift - add a new task to the front of the `queue`. |
|
* Invoke with `queue.unshift(task, [callback])`. |
|
* @property {Function} remove - remove items from the queue that match a test |
|
* function. The test function will be passed an object with a `data` property, |
|
* and a `priority` property, if this is a |
|
* [priorityQueue]{@link module:ControlFlow.priorityQueue} object. |
|
* Invoked with `queue.remove(testFn)`, where `testFn` is of the form |
|
* `function ({data, priority}) {}` and returns a Boolean. |
|
* @property {Function} saturated - a callback that is called when the number of |
|
* running workers hits the `concurrency` limit, and further tasks will be |
|
* queued. |
|
* @property {Function} unsaturated - a callback that is called when the number |
|
* of running workers is less than the `concurrency` & `buffer` limits, and |
|
* further tasks will not be queued. |
|
* @property {number} buffer - A minimum threshold buffer in order to say that |
|
* the `queue` is `unsaturated`. |
|
* @property {Function} empty - a callback that is called when the last item |
|
* from the `queue` is given to a `worker`. |
|
* @property {Function} drain - a callback that is called when the last item |
|
* from the `queue` has returned from the `worker`. |
|
* @property {Function} error - a callback that is called when a task errors. |
|
* Has the signature `function(error, task)`. |
|
* @property {boolean} paused - a boolean for determining whether the queue is |
|
* in a paused state. |
|
* @property {Function} pause - a function that pauses the processing of tasks |
|
* until `resume()` is called. Invoke with `queue.pause()`. |
|
* @property {Function} resume - a function that resumes the processing of |
|
* queued tasks when the queue is paused. Invoke with `queue.resume()`. |
|
* @property {Function} kill - a function that removes the `drain` callback and |
|
* empties remaining tasks from the queue forcing it to go idle. No more tasks |
|
* should be pushed to the queue after calling this function. Invoke with `queue.kill()`. |
|
*/ |
|
|
|
/** |
|
* Creates a `queue` object with the specified `concurrency`. Tasks added to the |
|
* `queue` are processed in parallel (up to the `concurrency` limit). If all |
|
* `worker`s are in progress, the task is queued until one becomes available. |
|
* Once a `worker` completes a `task`, that `task`'s callback is called. |
|
* |
|
* @name queue |
|
* @static |
|
* @memberOf module:ControlFlow |
|
* @method |
|
* @category Control Flow |
|
* @param {AsyncFunction} worker - An async function for processing a queued task. |
|
* If you want to handle errors from an individual task, pass a callback to |
|
* `q.push()`. Invoked with (task, callback). |
|
* @param {number} [concurrency=1] - An `integer` for determining how many |
|
* `worker` functions should be run in parallel. If omitted, the concurrency |
|
* defaults to `1`. If the concurrency is `0`, an error is thrown. |
|
* @returns {module:ControlFlow.QueueObject} A queue object to manage the tasks. Callbacks can |
|
* attached as certain properties to listen for specific events during the |
|
* lifecycle of the queue. |
|
* @example |
|
* |
|
* // create a queue object with concurrency 2 |
|
* var q = async.queue(function(task, callback) { |
|
* console.log('hello ' + task.name); |
|
* callback(); |
|
* }, 2); |
|
* |
|
* // assign a callback |
|
* q.drain = function() { |
|
* console.log('all items have been processed'); |
|
* }; |
|
* |
|
* // add some items to the queue |
|
* q.push({name: 'foo'}, function(err) { |
|
* console.log('finished processing foo'); |
|
* }); |
|
* q.push({name: 'bar'}, function (err) { |
|
* console.log('finished processing bar'); |
|
* }); |
|
* |
|
* // add some items to the queue (batch-wise) |
|
* q.push([{name: 'baz'},{name: 'bay'},{name: 'bax'}], function(err) { |
|
* console.log('finished processing item'); |
|
* }); |
|
* |
|
* // add some items to the front of the queue |
|
* q.unshift({name: 'bar'}, function (err) { |
|
* console.log('finished processing bar'); |
|
* }); |
|
*/ |