// Writing to a log file

// Importing required packages
const process = require("process");
const fs = require("fs");
const os = require("os");
const cron = require("node-cron");
const express = require("express");

app = express();

// setting a cron job for every 15 seconds
cron.schedule("*/15 * * * * *", function () {
  let heap = process.memoryUsage().heapUsed / 1024 / 1024;
  let date = new Date().toISOString();
  const freeMemory = Math.round((os.freemem() * 100) / os.totalmem()) + "%";

  //          date | heap used | free memory
  let csv = `${date}, ${heap}, ${freeMemory}\n`;

  // storing log In .csv file
  fs.appendFile("demo.csv", csv, function (err) {
    if (err) throw err;
    console.log("server details logged!");
  });
});

app.listen(3000, () => {
  console.log("application listening.....");
});

/*
* Run the script: `node example3.js`
* To generate logstatus.txt file
* at scheduled time
*/