Read and overwrite a json file in node.js.

read-overwrite-json.js

const fs = require('fs');

const filePath = 'file/path.json';
const fileObject = JSON.parse(fs.readFileSync(filePath, 'utf8'));

// Do something with file

try {
	fs.writeFileSync(filePath, JSON.stringify(fileObject, null, 2), 'utf8');
	console.log("The file was saved!");
}
catch(err) {
	console.err("An error has ocurred when saving the file.");
}