187 lines
4.6 KiB
Markdown
187 lines
4.6 KiB
Markdown
|
Node.js - jsonfile
|
||
|
================
|
||
|
|
||
|
Easily read/write JSON files.
|
||
|
|
||
|
[![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)
|
||
|
|
||
|
<a href="https://github.com/feross/standard"><img src="https://cdn.rawgit.com/feross/standard/master/sticker.svg" alt="Standard JavaScript" width="100"></a>
|
||
|
|
||
|
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)
|
||
|
|
||
|
`options` (`object`, default `undefined`): Pass in any `fs.readFile` 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
|
||
|
var jsonfile = require('jsonfile')
|
||
|
var file = '/tmp/data.json'
|
||
|
jsonfile.readFile(file, function(err, obj) {
|
||
|
console.dir(obj)
|
||
|
})
|
||
|
```
|
||
|
|
||
|
|
||
|
### readFileSync(filename, [options])
|
||
|
|
||
|
`options` (`object`, default `undefined`): Pass in any `fs.readFileSync` 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
|
||
|
var jsonfile = require('jsonfile')
|
||
|
var file = '/tmp/data.json'
|
||
|
|
||
|
console.dir(jsonfile.readFileSync(file))
|
||
|
```
|
||
|
|
||
|
|
||
|
### writeFile(filename, obj, [options], callback)
|
||
|
|
||
|
`options`: Pass in any `fs.writeFile` 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`.
|
||
|
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
|
||
|
var file = '/tmp/data.json'
|
||
|
var obj = {name: 'JP'}
|
||
|
|
||
|
jsonfile.writeFile(file, obj, function (err) {
|
||
|
console.error(err)
|
||
|
})
|
||
|
```
|
||
|
|
||
|
**formatting with spaces:**
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
|
||
|
var file = '/tmp/data.json'
|
||
|
var obj = {name: 'JP'}
|
||
|
|
||
|
jsonfile.writeFile(file, obj, {spaces: 2}, function(err) {
|
||
|
console.error(err)
|
||
|
})
|
||
|
```
|
||
|
|
||
|
**appending to an existing JSON file:**
|
||
|
|
||
|
You can use `fs.writeFile` option `{flag: 'a'}` to achieve this.
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
|
||
|
var file = '/tmp/mayAlreadyExistedData.json'
|
||
|
var obj = {name: 'JP'}
|
||
|
|
||
|
jsonfile.writeFile(file, obj, {flag: 'a'}, function (err) {
|
||
|
console.error(err)
|
||
|
})
|
||
|
```
|
||
|
|
||
|
### writeFileSync(filename, obj, [options])
|
||
|
|
||
|
`options`: Pass in any `fs.writeFileSync` 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`.
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
|
||
|
var file = '/tmp/data.json'
|
||
|
var obj = {name: 'JP'}
|
||
|
|
||
|
jsonfile.writeFileSync(file, obj)
|
||
|
```
|
||
|
|
||
|
**formatting with spaces:**
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
|
||
|
var file = '/tmp/data.json'
|
||
|
var obj = {name: 'JP'}
|
||
|
|
||
|
jsonfile.writeFileSync(file, obj, {spaces: 2})
|
||
|
```
|
||
|
|
||
|
**appending to an existing JSON file:**
|
||
|
|
||
|
You can use `fs.writeFileSync` option `{flag: 'a'}` to achieve this.
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
|
||
|
var file = '/tmp/mayAlreadyExistedData.json'
|
||
|
var obj = {name: 'JP'}
|
||
|
|
||
|
jsonfile.writeFileSync(file, obj, {flag: 'a'})
|
||
|
```
|
||
|
|
||
|
### spaces
|
||
|
|
||
|
Global configuration to set spaces to indent JSON files.
|
||
|
|
||
|
**default:** `null`
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
|
||
|
jsonfile.spaces = 4
|
||
|
|
||
|
var file = '/tmp/data.json'
|
||
|
var obj = {name: 'JP'}
|
||
|
|
||
|
// json file has four space indenting now
|
||
|
jsonfile.writeFile(file, obj, function (err) {
|
||
|
console.error(err)
|
||
|
})
|
||
|
```
|
||
|
|
||
|
Note, it's bound to `this.spaces`. So, if you do this:
|
||
|
|
||
|
```js
|
||
|
var myObj = {}
|
||
|
myObj.writeJsonSync = jsonfile.writeFileSync
|
||
|
// => this.spaces = null
|
||
|
```
|
||
|
|
||
|
Could do the following:
|
||
|
|
||
|
```js
|
||
|
var jsonfile = require('jsonfile')
|
||
|
jsonfile.spaces = 4
|
||
|
jsonfile.writeFileSync(file, obj) // will have 4 spaces indentation
|
||
|
|
||
|
var myCrazyObj = {spaces: 32}
|
||
|
myCrazyObj.writeJsonSync = jsonfile.writeFileSync
|
||
|
myCrazyObj.writeJsonSync(file, obj) // will have 32 space indentation
|
||
|
myCrazyObj.writeJsonSync(file, obj, {spaces: 2}) // will have only 2
|
||
|
```
|
||
|
|
||
|
|
||
|
License
|
||
|
-------
|
||
|
|
||
|
(MIT License)
|
||
|
|
||
|
Copyright 2012-2016, JP Richardson <jprichardson@gmail.com>
|