MAINHACK

Viewing / Editing File: README.md

Node.js - jsonfile
================

Easily read/write JSON files in Node.js. _Note: this module cannot be used in the browser._

[![npm Package](https://img.shields.io/npm/v/jsonfile.svg?style=flat-square)](https://www.npmjs.org/package/jsonfile)
[![build status](https://secure.travis-ci.org/jprichardson/node-jsonfile.svg)](http://travis-ci.org/jprichardson/node-jsonfile)
[![windows Build status](https://img.shields.io/appveyor/ci/jprichardson/node-jsonfile/master.svg?label=windows%20build)](https://ci.appveyor.com/project/jprichardson/node-jsonfile/branch/master)

Why?
----

Writing `JSON.stringify()` and then `fs.writeFile()` and `JSON.parse()` with `fs.readFile()` enclosed in `try/catch` blocks became annoying.

Installation
------------

npm install --save jsonfile

API
---

* [`readFile(filename, [options], callback)`](#readfilefilename-options-callback)
* [`readFileSync(filename, [options])`](#readfilesyncfilename-options)
* [`writeFile(filename, obj, [options], callback)`](#writefilefilename-obj-options-callback)
* [`writeFileSync(filename, obj, [options])`](#writefilesyncfilename-obj-options)

----

### readFile(filename, [options], callback)

`options` (`object`, default `undefined`): Pass in any [`fs.readFile`](https://nodejs.org/api/fs.html#fs_fs_readfile_path_options_callback) options or set `reviver` for a [JSON reviver](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse).
  - `throws` (`boolean`, default: `true`). If `JSON.parse` throws an error, pass this error to the callback.
  If `false`, returns `null` for the object.

```js
const jsonfile = require('jsonfile')
const file = '/tmp/data.json'
jsonfile.readFile(file, function (err, obj) {
  if (err) console.error(err)
  console.dir(obj)
})
```

You can also use this method with promises. The `readFile` method will return a promise if you do not pass a callback function.

```js
const jsonfile = require('jsonfile')
const file = '/tmp/data.json'
jsonfile.readFile(file)
  .then(obj => console.dir(obj))
  .catch(error => console.error(error))
```

----

### readFileSync(filename, [options])

`options` (`object`, default `undefined`): Pass in any [`fs.readFileSync`](https://nodejs.org/api/fs.html#fs_fs_readfilesync_path_options) options or set `reviver` for a [JSON reviver](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse).
- `throws` (`boolean`, default: `true`). If an error is encountered reading or parsing the file, throw the error. If `false`, returns `null` for the object.

```js
const jsonfile = require('jsonfile')
const file = '/tmp/data.json'

console.dir(jsonfile.readFileSync(file))
```

----

### writeFile(filename, obj, [options], callback)

`options`: Pass in any [`fs.writeFile`](https://nodejs.org/api/fs.html#fs_fs_writefile_file_data_options_callback) options or set `replacer` for a [JSON replacer](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify). Can also pass in `spaces`, or override `EOL` string or set `finalEOL` flag as `false` to not save the file with `EOL` at the end.