cargoQueue.js 3.3 KB

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  1. 'use strict';
  2. Object.defineProperty(exports, "__esModule", {
  3. value: true
  4. });
  5. exports.default = cargo;
  6. var _queue = require('./internal/queue.js');
  7. var _queue2 = _interopRequireDefault(_queue);
  8. function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
  9. /**
  10. * Creates a `cargoQueue` object with the specified payload. Tasks added to the
  11. * cargoQueue will be processed together (up to the `payload` limit) in `concurrency` parallel workers.
  12. * If the all `workers` are in progress, the task is queued until one becomes available. Once
  13. * a `worker` has completed some tasks, each callback of those tasks is
  14. * called. Check out [these](https://camo.githubusercontent.com/6bbd36f4cf5b35a0f11a96dcd2e97711ffc2fb37/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130382f62626330636662302d356632392d313165322d393734662d3333393763363464633835382e676966) [animations](https://camo.githubusercontent.com/f4810e00e1c5f5f8addbe3e9f49064fd5d102699/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130312f38346339323036362d356632392d313165322d383134662d3964336430323431336266642e676966)
  15. * for how `cargo` and `queue` work.
  16. *
  17. * While [`queue`]{@link module:ControlFlow.queue} passes only one task to one of a group of workers
  18. * at a time, and [`cargo`]{@link module:ControlFlow.cargo} passes an array of tasks to a single worker,
  19. * the cargoQueue passes an array of tasks to multiple parallel workers.
  20. *
  21. * @name cargoQueue
  22. * @static
  23. * @memberOf module:ControlFlow
  24. * @method
  25. * @see [async.queue]{@link module:ControlFlow.queue}
  26. * @see [async.cargo]{@link module:ControlFLow.cargo}
  27. * @category Control Flow
  28. * @param {AsyncFunction} worker - An asynchronous function for processing an array
  29. * of queued tasks. Invoked with `(tasks, callback)`.
  30. * @param {number} [concurrency=1] - An `integer` for determining how many
  31. * `worker` functions should be run in parallel. If omitted, the concurrency
  32. * defaults to `1`. If the concurrency is `0`, an error is thrown.
  33. * @param {number} [payload=Infinity] - An optional `integer` for determining
  34. * how many tasks should be processed per round; if omitted, the default is
  35. * unlimited.
  36. * @returns {module:ControlFlow.QueueObject} A cargoQueue object to manage the tasks. Callbacks can
  37. * attached as certain properties to listen for specific events during the
  38. * lifecycle of the cargoQueue and inner queue.
  39. * @example
  40. *
  41. * // create a cargoQueue object with payload 2 and concurrency 2
  42. * var cargoQueue = async.cargoQueue(function(tasks, callback) {
  43. * for (var i=0; i<tasks.length; i++) {
  44. * console.log('hello ' + tasks[i].name);
  45. * }
  46. * callback();
  47. * }, 2, 2);
  48. *
  49. * // add some items
  50. * cargoQueue.push({name: 'foo'}, function(err) {
  51. * console.log('finished processing foo');
  52. * });
  53. * cargoQueue.push({name: 'bar'}, function(err) {
  54. * console.log('finished processing bar');
  55. * });
  56. * cargoQueue.push({name: 'baz'}, function(err) {
  57. * console.log('finished processing baz');
  58. * });
  59. * cargoQueue.push({name: 'boo'}, function(err) {
  60. * console.log('finished processing boo');
  61. * });
  62. */
  63. function cargo(worker, concurrency, payload) {
  64. return (0, _queue2.default)(worker, concurrency, payload);
  65. }
  66. module.exports = exports['default'];