Boilerplate to parse JSON in Javascript

parse_json.js

#!/usr/bin/env node

const fs = require('fs');

const filename = process.argv[2];
if (filename == null) {
  console.log("Usage: parse_json.js FILENAME.json")
  process.exit(1);
}

const fileContents = fs.readFileSync(filename, { encoding: 'utf8' });
const data = JSON.parse(fileContents);

console.log(JSON.stringify(data, null, 2));