work.suroh.tk/node_modules/jsonfile/README.md

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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)
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<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>