Template string vs JSON.stringify test

templateStringVsJsonStringify.js

'use strict';

const NS_PER_SEC = 1e9;
const MS_PER_NS = 1e6;
const ITEMS = 100000;

const data = getData();

run();
runWithTemplate();

function run() {
  const timer = getTimer();

  data.map(item => JSON.stringify(item));

  console.log(`Without template took ${timer.elapsed()}ms`);
}

function runWithTemplate() {
  const timer = getTimer();

  data.map(item => `{
    "id": ${item.id},
    "username": "${item.username}",
    "age": ${item.age},
    "stats": {
      "friends": ${item.stats.friends},
      "posts": ${item.stats.posts},
    }
  }`);

  console.log(`With template took ${timer.elapsed()}ms`);
}

function getTimer() {
  const time =  process.hrtime();

  return {
    elapsed() {
      const [seconds, nanoseconds] = process.hrtime(time);
      return ((seconds * NS_PER_SEC) + nanoseconds) / MS_PER_NS;
    }
  }
}

function getData() {
  const data = [];
  
  for (let i = 0; i < ITEMS; i++) {
    data.push({
      id: Math.random(),
      username: 'John Doe',
      age: 29,
      stats: {
        friends: 3,
        posts: 203
      }
    });
  }
  
  return data;
}