is there a require for json in node.js

Question

I would like to include a couple of JSON files in my JavaScript code that are in the same directory as my JavaScript source file.

If I wanted to include another JavaScript file I could simply use require. Now I'm using readFileSync and __dirname to get the JSON, which I think is an ugly way to do it.

Is there something similar for require that enables me to load a JSON file?

Answer 1

As of node v0.5.x yes you can require your JSON just as you would require a js file.

var someObject = require('./somefile.json')

In ES6:

import someObject from ('./somefile.json')

Answer 2

JSON files don’t require an explicit exports statement. You don't need to export to use it as Javascript files.

So, you can use just require for valid JSON document.

data.json

{
  "name": "Freddie Mercury"
}

main.js

var obj = require('data.json');

console.log(obj.name); 
//Freddie Mercury

Answer 3

Two of the most common

First way :

let jsonData = require('./JsonFile.json')

let jsonData = require('./JsonFile') // if we omitting .json also works

OR

import jsonData from ('./JsonFile.json')

Second way :

1) synchronously

const fs = require('fs')
let jsonData = JSON.parse(fs.readFileSync('JsonFile.json', 'utf-8'))

2) asynchronously

const fs = require('fs')
let jsonData = {}
fs.readFile('JsonFile.json', 'utf-8', (err, data) => {
  if (err) throw err

  jsonData = JSON.parse(data)
})

Note: 1) if we JsonFile.json is changed, we not get the new data, even if we re run require('./JsonFile.json')

2) The fs.readFile or fs.readFileSync will always re read the file, and get changes

Answer 4

No. Either use readFile or readFileSync (The latter only at startup time).

Or use an existing library like

• cjson

Alternatively write your config in a js file rather then a json file like

module.exports = {
  // json
}

Answer 5

You can import json files by using the node.js v14 experimental json modules flag. More details here

file.js

import data from './folder/file.json'

export default {
  foo () {
    console.log(data)
  }
}

And you call it with node --experimental-json-modules file.js

Answer 6

A nifty non-caching async one liner for node 15 modules:

import { readFile } from 'fs/promises';

const data = await readFile('{{ path }}').then(json => JSON.parse(json)).catch(() => null);

Answer 7

You even can use require of your JSON without specifying the extension .json. It will let you change the file extension to .js without any changes in your imports.

assuming we have ./myJsonFile.json in the same directory.

const data = require('./myJsonFile')

If in the future you'll change ./myJsonFile.json to ./myJsonFile.js nothing should be changed in the import.

Answer 8

You can use a module to create a require.

import { createRequire } from 'module'
const require = createRequire(import.meta.url)
const foo = require('./foo.js')

Answer 9

if you are using typescript, you can just add in your tsconfig.json a new field called resolveJsonModule: true, and then you can import all the informations of any .json file just like this:

import * as jsonfile from "./path/to/json"