Object Auger

Safely get or set values in nested objects and arrays.

Installation

npm install --save object-auger

Usage

See the tests for more examples. Passing

const auger = require('object-auger');

let haystack = {};

haystack = auger.set(haystack, ['a', 'b', 'c', 0], 'needle');
// => { a: { b: { c: ['needle'] } } }

auger.has(haystack, ['a', 'b', 'c']);
// => true

auger.get(haystack, ['a', 'b', 'c', 0]);
// => 'needle'

auger.get(haystack, ['a', 'b', 'c', 1], 'no needle here');
// => 'no needle here'

auger.has(object, path)

Safely check if a value exists in an object. Returns a boolean.

object

Type: object or array

Object to look for a value in.

path

Type: array

Path to the value.

auger.get(object, path, defaultValue)

Safely retrieve a value from an object. Returns the retrieved value or the defaultValue if the it cannot be found.

object

Type: object or array

Object to retrieve a value from.

path

Type: array

Path to the value.

default

Type: any Default: undefined

Default value. (Optional)

auger.set(object, path, value)

Safely set a value in an object. Returns the new object.

object

Type: object or array

Object to set a value in.

path

Type: array

Path to where the value will be set.

value

Type: any

Value to set at the path.

Why?

There are tons of other libraries that have similar functionality (notably dot-prop and lodash). While these packages are great, they can cause confusion when working with arrays in a nested object.

Trying to set an object with a number as the key in lodash will result in an array:

const _ = require('lodash');

_.set({}, ['a', '0'], 'b');
// => { a: [ 'b' ] }
// Expected => { a: { '0': 'b' } }

_.set({}, ['a', 0], 'b');
// => { a: [ 'b' ] }
// Expected => { a: [ 'b' ] }

Using the same dot path syntax with lodash and dot-prop will result in different outcomes:

const _ = require('lodash');
const dotProp = require('dot-prop');

_.set({}, 'a.0', 'b');
// => { a: [ 'b' ] }

dotProp.set({}, 'a.0', 'b');
// => { a: { '0': 'b' } }

With the dot path syntax, it's hard to tell if you're working with an array index number or an object property key. Dot path also makes it difficult to dynamically build up the path.

With object-auger, you can set the value and know exactly what the outcome will be:

const auger = require('object-auger');

auger.set({}, ['a', '0'], 'b');
// => { a: { '0': 'b' } }

auger.set({}, ['a', 0], 'b');
// => { a: [ 'b' ] }

License

This project is licensed under the MIT License - see the LICENSE file for details