File size: 4,590 Bytes
bc20498 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 |
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = mapValues;
var _mapValuesLimit = require('./mapValuesLimit.js');
var _mapValuesLimit2 = _interopRequireDefault(_mapValuesLimit);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
/**
* 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 ]
* }
* }
*
*/
function mapValues(obj, iteratee, callback) {
return (0, _mapValuesLimit2.default)(obj, Infinity, iteratee, callback);
}
module.exports = exports.default; |