Create a Flame Graph for your node app | Profiling nodeJS app

app.js

//app.js
const express = require('express');
const console = require('console');
const levenshtein = require('fast-levenshtein');
var arr=[];
const HOW_OBVIOUS_THE_FLAME_GRAPH_SHOULD_BE_ON_SCALE_1_TO_100 = 10;

const someFakeModule = (function someFakeModule () {
return {
  calculateStringDistance (a, b) {
    return levenshtein.get(a, b, {
    useCollator: true
    })
  }
 }
})()

const app = express();

app.get('/', (req, res) => {
  res.send(`
  <h2>Take a look at the network tab in devtools</h2>
  <script>
    function loops(func) {
    return func().then(_ => setTimeout(loops, 20, func))
    }
    loops(_ => fetch('api/tick'))
  </script>\
  `)
});

app.get('/api/tick', (req, res) => {
  arr.push({name:'Shubham'});
  Promise.resolve('asynchronous flow will make our stacktrace more realistic'.repeat(HOW_OBVIOUS_THE_FLAME_GRAPH_SHOULD_BE_ON_SCALE_1_TO_100))
  .then(text => {
    const randomText =Math.random().toString(32).repeat(HOW_OBVIOUS_THE_FLAME_GRAPH_SHOULD_BE_ON_SCALE_1_TO_100)
    return someFakeModule.calculateStringDistance(text, randomText)
  })
  .then(result => res.end(`result: ${result}, ${arr.length}`))
});

app.get('/api/end', () => process.exit());

app.listen(8080, () => {
  console.log(`go to http://localhost:8080/ to generate traffic`)
});