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How to write a JSON object to file in Node.js

Discover how to save a JSON object to file in Node.js, and retrieve it later

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.

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