@exponent/json-file v5.3.0

json-file

A module for reading, writing, and manipulating JSON files

Importing the package

import JsonFile from '@exponent/json-file';

Promise-based async API

Everything returns Promises. If you are using ES7 (or Babel), you can write code like this:

let config = await JsonFile.readAsync('config.json', {cantReadFileDefault: {}});

If you are using ES6, you can just use the return values the way you normally would use Promises.

JsonFile.readAsync('config.json', {cantReadFileDefault: {}}).then(config => {
   ...
});

Used as an object

var file = new JsonFile('config.json', {cantReadFileDefault: {}});
var somethingSaved = await file.getAsync('somethingSaved', null);

Used as functions

var pkg = await JsonFile.readAsync('package.json');
var main = await JsonFile.getAsync('package.json', 'main', 'index.js');
...

Options you can set, and their default values

• Note that if defaults are undefined, then an Error will be thrown instead of undefined being returned

Methods

.readAsync(options)

Returns the parse of the whole file as an object

.getAsync(key, default-value, options)

Returns a single value from a JSON file, using lodash's _.get to query the whole object.

See https://lodash.com/docs#get

.writeAsync(data, options)

Writes out the given data to the file

.setAsync(key, val, options)

Updates the file, inserting or updating the value for <key> with <val>

.mergeAsync(sources, options)

Merges the values in <sources> into the object currently encoded in the file.

.deleteKeyAsync(key, options)

Deletes a single key from the top level of the file.

Functions

The functions available all mirror the methods above but take file (filename as a string) as their first argument.