import mapValuesLimit from './mapValuesLimit.js' /** * A relative of [`map`]{@link module:Collections.map}, designed for use with objects. * * Produces a new Object by mapping each value of `obj` through the `iteratee` * function. The `iteratee` is called each `value` and `key` from `obj` and a * callback for when it has finished processing. Each of these callbacks takes * two arguments: an `error`, and the transformed item from `obj`. If `iteratee` * passes an error to its callback, the main `callback` (for the `mapValues` * function) is immediately called with the error. * * Note, the order of the keys in the result is not guaranteed. The keys will * be roughly in the order they complete, (but this is very engine-specific) * * @name mapValues * @static * @memberOf module:Collections * @method * @category Collection * @param {Object} obj - A collection to iterate over. * @param {AsyncFunction} iteratee - A function to apply to each value and key * in `coll`. * The iteratee should complete with the transformed value as its result. * Invoked with (value, key, callback). * @param {Function} [callback] - A callback which is called when all `iteratee` * functions have finished, or an error occurs. `result` is a new object consisting * of each key from `obj`, with each transformed value on the right-hand side. * Invoked with (err, result). * @returns {Promise} a promise, if no callback is passed * @example * * // file1.txt is a file that is 1000 bytes in size * // file2.txt is a file that is 2000 bytes in size * // file3.txt is a file that is 3000 bytes in size * // file4.txt does not exist * * const fileMap = { * f1: 'file1.txt', * f2: 'file2.txt', * f3: 'file3.txt' * }; * * const withMissingFileMap = { * f1: 'file1.txt', * f2: 'file2.txt', * f3: 'file4.txt' * }; * * // asynchronous function that returns the file size in bytes * function getFileSizeInBytes(file, key, callback) { * fs.stat(file, function(err, stat) { * if (err) { * return callback(err); * } * callback(null, stat.size); * }); * } * * // Using callbacks * async.mapValues(fileMap, getFileSizeInBytes, function(err, result) { * if (err) { * console.log(err); * } else { * console.log(result); * // result is now a map of file size in bytes for each file, e.g. * // { * // f1: 1000, * // f2: 2000, * // f3: 3000 * // } * } * }); * * // Error handling * async.mapValues(withMissingFileMap, getFileSizeInBytes, function(err, result) { * if (err) { * console.log(err); * // [ Error: ENOENT: no such file or directory ] * } else { * console.log(result); * } * }); * * // Using Promises * async.mapValues(fileMap, getFileSizeInBytes) * .then( result => { * console.log(result); * // result is now a map of file size in bytes for each file, e.g. * // { * // f1: 1000, * // f2: 2000, * // f3: 3000 * // } * }).catch (err => { * console.log(err); * }); * * // Error Handling * async.mapValues(withMissingFileMap, getFileSizeInBytes) * .then( result => { * console.log(result); * }).catch (err => { * console.log(err); * // [ Error: ENOENT: no such file or directory ] * }); * * // Using async/await * async () => { * try { * let result = await async.mapValues(fileMap, getFileSizeInBytes); * console.log(result); * // result is now a map of file size in bytes for each file, e.g. * // { * // f1: 1000, * // f2: 2000, * // f3: 3000 * // } * } * catch (err) { * console.log(err); * } * } * * // Error Handling * async () => { * try { * let result = await async.mapValues(withMissingFileMap, getFileSizeInBytes); * console.log(result); * } * catch (err) { * console.log(err); * // [ Error: ENOENT: no such file or directory ] * } * } * */ export default function mapValues(obj, iteratee, callback) { return mapValuesLimit(obj, Infinity, iteratee, callback) }