Async.js

eachSeries.js

  1. import eachLimit from './eachLimit.js'
  2. import awaitify from './internal/awaitify.js'
  4. /**
  5.  * The same as [`each`]{@link module:Collections.each} but runs only a single async operation at a time.
  6.  *
  7.  * Note, that unlike [`each`]{@link module:Collections.each}, this function applies iteratee to each item
  8.  * in series and therefore the iteratee functions will complete in order.
  10.  * @name eachSeries
  11.  * @static
  12.  * @memberOf module:Collections
  13.  * @method
  14.  * @see [async.each]{@link module:Collections.each}
  15.  * @alias forEachSeries
  16.  * @category Collection
  17.  * @param {Array|Iterable|AsyncIterable|Object} coll - A collection to iterate over.
  18.  * @param {AsyncFunction} iteratee - An async function to apply to each
  19.  * item in `coll`.
  20.  * The array index is not passed to the iteratee.
  21.  * If you need the index, use `eachOfSeries`.
  22.  * Invoked with (item, callback).
  23.  * @param {Function} [callback] - A callback which is called when all
  24.  * `iteratee` functions have finished, or an error occurs. Invoked with (err).
  25.  * @returns {Promise} a promise, if a callback is omitted
  26.  */
  27. function eachSeries(coll, iteratee, callback) {
  28.     return eachLimit(coll, 1, iteratee, callback)
  29. }
  30. export default awaitify(eachSeries, 3);