168 lines
4.2 KiB
Markdown
168 lines
4.2 KiB
Markdown
Node.js - jsonfile
|
|
================
|
|
|
|
Easily read/write JSON files.
|
|
|
|
[](https://www.npmjs.org/package/jsonfile)
|
|
[](http://travis-ci.org/jprichardson/node-jsonfile)
|
|
[](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` and override `EOL` string.
|
|
|
|
|
|
```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)
|
|
})
|
|
```
|
|
|
|
**overriding EOL:**
|
|
|
|
```js
|
|
var jsonfile = require('jsonfile')
|
|
|
|
var file = '/tmp/data.json'
|
|
var obj = {name: 'JP'}
|
|
|
|
jsonfile.writeFile(file, obj, {spaces: 2, EOL: '\r\n'}, 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` and override `EOL` string.
|
|
|
|
```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})
|
|
```
|
|
|
|
**overriding EOL:**
|
|
|
|
```js
|
|
var jsonfile = require('jsonfile')
|
|
|
|
var file = '/tmp/data.json'
|
|
var obj = {name: 'JP'}
|
|
|
|
jsonfile.writeFileSync(file, obj, {spaces: 2, EOL: '\r\n'})
|
|
```
|
|
|
|
**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'})
|
|
```
|
|
|
|
License
|
|
-------
|
|
|
|
(MIT License)
|
|
|
|
Copyright 2012-2016, JP Richardson <jprichardson@gmail.com>
|