Node.js app crashing when trying to download large files using it

I am trying to write a program that can convert HTTP URLs to torrents. This project is working basically working for download links contain small files. Like a file of 1-500Mb. My problem is if the file size is more than that the app is crashing or getting a timeout. So I want to know how to fix this. Below is link to my Github.https://github.com/savadks95/FireBitvar http          = require('http');var webtorrentify = require('webtorrentify-link');var fs            = require('fs');var url           = require("url");var path          = require("path");var validUrl      = require('valid-url');var express       = require('express');var getUrls       = require('get-urls');var remote        = require('remote-file-size');var app           = express();var downloadLink;var fileName;var fileSize;var server;var parsed;var param;var link;var port;port = process.env.PORT || 80;app.get('/favicon.ico', function(req, res){console.log('favicon request recived');});app.get('*', function(req, res){if(req.url==='/'){//app.use('/public/html', express.static(path.join(__dirname)));fs.readFile('public/html/index.html', function (err, data) {res.write(data);    });  }else if (req.url === '/l?thelink='){fs.readFile('public/html/emptyRequest.html', function (err, data) {res.write(data);res.end();  });}else{//---------Reciving Url--------------------console.log(req.query.thelink);downloadLink=req.query.thelink;//-----------------------------------------//------------checking for valid url-------if (validUrl.isUri(downloadLink)) {console.log('Looks like an URI');//-----------------------------------------//----------Extracting filename-------------parsed = url.parse(downloadLink);fileName = path.basename(parsed.pathname);console.log(path.basename(parsed.pathname));//-------------------------------------------//----------Finding File size----------------remote(downloadLink, function(err, o) {fileSize = (o/1024)/1024;console.log('size of ' + fileName + ' = ' + fileSize+" MB");  //-------------------------------------------if (fileSize <� 2500){///////////////Creating Torrent////////////////////webtorrentify(downloadLink).then(function (buffer) {console.log('creating the torrent');//res.send('what is');//-------------------------------------------res.setHeader('Content-Type', 'application/x-bittorrent');res.setHeader('Content-Disposition', `inline; filename="${fileName}.torrent"`);res.setHeader('Cache-Control', 'public, max-age=2592000'); // 30 daysres.send(buffer);console.log(fileName+'.torrent created');res.end();//-------------------------------------------});////////////////////////////////////////////////}else{console.log('More than 500 MB');res.send("

 More than 500 MB or invalid URL 

");}  });  }else {console.log('not url');fs.readFile('public/html/404.html', function (err, data) {res.write(data);res.end();});  }}});app.listen(port);console.log('server up and running', port);

Submitted June 27, 2020 at 09:25PM by savadks1818