Sometimes the best way to store some data in a Node.js application is to save it to the filesystem.

If you have an object that can be serialized to JSON, you can use the JSON.stringify() method and the fs method fs.writeFileSync() which synchronously writes a piece of data to a file:

const fs = require('fs')

const storeData = (data, path) => {
  try {
    fs.writeFileSync(path, JSON.stringify(data))
  } catch (err) {
    console.error(err)
  }
}

To retrieve the data, you can use fs.readFileSync():

const loadData = (path) => {
  try {
    return fs.readFileSync(path, 'utf8')
  } catch (err) {
    console.error(err)
    return false
  }
}

We used a synchronous API, so we can easily return the data once we get it.

We can also decide to use the asynchronous versions, fs.writeFile and fs.readFile, although the code will change a little bit, and I recommend you take a read at how to write files using Node.js and how to read files using Node.js for this.

Lessons in this unit:

0:	Introduction
1:	How to check if a file exists in Node.js
2:	How to create an empty file in Node.js
3:	How to get the names of all the files in a folder in Node
4:	How to get the last updated date of a file using Node.js
5:	How to remove a file with Node.js
6:	▶︎ How to write a JSON object to file in Node.js
7:	How to empty a folder in Node.js
8:	Working with file descriptors in Node
9:	Node File Paths
10:	Node file stats
11:	Working with folders in Node
12:	How to use the Node.js fs module with async/await
13:	How to get the current folder in Node
14:	How to get the file extension in Node.js from the MIME type
15:	How to get the file extension in Node.js
16:	How to list files in a folder in Node
17:	How to mass rename files in Node.js
18:	Node.js get all files in a folder recursively
19:	Incrementing multiple folders numbers at once using Node.js
20:	Save some text to a file in Node.js