blob: e71e4e016951a1ee42230e6002431e1223356632 [file] [log] [blame]
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = cargo;
var _queue = require('./internal/queue');
var _queue2 = _interopRequireDefault(_queue);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
/**
* Creates a `cargoQueue` object with the specified payload. Tasks added to the
* cargoQueue will be processed together (up to the `payload` limit) in `concurrency` parallel workers.
* If the all `workers` are in progress, the task is queued until one becomes available. Once
* a `worker` has completed some tasks, each callback of those tasks is
* called. Check out [these](https://camo.githubusercontent.com/6bbd36f4cf5b35a0f11a96dcd2e97711ffc2fb37/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130382f62626330636662302d356632392d313165322d393734662d3333393763363464633835382e676966) [animations](https://camo.githubusercontent.com/f4810e00e1c5f5f8addbe3e9f49064fd5d102699/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130312f38346339323036362d356632392d313165322d383134662d3964336430323431336266642e676966)
* for how `cargo` and `queue` work.
*
* While [`queue`]{@link module:ControlFlow.queue} passes only one task to one of a group of workers
* at a time, and [`cargo`]{@link module:ControlFlow.cargo} passes an array of tasks to a single worker,
* the cargoQueue passes an array of tasks to multiple parallel workers.
*
* @name cargoQueue
* @static
* @memberOf module:ControlFlow
* @method
* @see [async.queue]{@link module:ControlFlow.queue}
* @see [async.cargo]{@link module:ControlFLow.cargo}
* @category Control Flow
* @param {AsyncFunction} worker - An asynchronous function for processing an array
* of queued tasks. Invoked with `(tasks, 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.
* @param {number} [payload=Infinity] - An optional `integer` for determining
* how many tasks should be processed per round; if omitted, the default is
* unlimited.
* @returns {module:ControlFlow.CargoObject} A cargoQueue object to manage the tasks. Callbacks can
* attached as certain properties to listen for specific events during the
* lifecycle of the cargoQueue and inner queue.
* @example
*
* // create a cargoQueue object with payload 2 and concurrency 2
* var cargoQueue = async.cargoQueue(function(tasks, callback) {
* for (var i=0; i<tasks.length; i++) {
* console.log('hello ' + tasks[i].name);
* }
* callback();
* }, 2, 2);
*
* // add some items
* cargoQueue.push({name: 'foo'}, function(err) {
* console.log('finished processing foo');
* });
* cargoQueue.push({name: 'bar'}, function(err) {
* console.log('finished processing bar');
* });
* cargoQueue.push({name: 'baz'}, function(err) {
* console.log('finished processing baz');
* });
* cargoQueue.push({name: 'boo'}, function(err) {
* console.log('finished processing boo');
* });
*/
function cargo(worker, concurrency, payload) {
return (0, _queue2.default)(worker, concurrency, payload);
}
module.exports = exports['default'];