Experimenting with Node.js - Part 01

Basic server

var http = require('http');
var dt = require('./myfirstmodule');


http.createServer(function (req, res) {

  // res.writeHead(200, {'Content-Type': 'text/plain'});
  // res.write("The date and time are currently: " + dt.myDateTime());
  // res.end('\nHello World!');

  res.writeHead(200, {'Content-Type': 'text/html'});
  res.write("The date and time are currently: " + dt.myDateTime());
  res.end('<br>Hello World!');

}).listen(8080);

console.log('This example is different!');
console.log('The result is displayed in the Command Line Interface');

Module

exports.myDateTime = function () {
  return Date();
};

Query Parse URL

var http = require('http');
var url = require('url');

http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/html'});
  var q = url.parse(req.url, true).query;
  var txt = q.year + " " + q.month;
  res.end(txt);
}).listen(8080);

File operations


// Using ES modules with fs/promises for proper await support
import { writeFile, appendFile, rename, unlink } from 'fs/promises';

// Async function to execute file operations sequentially
async function runFileOperations() {
  try {
    // Create first file
    await writeFile('mynewfile3.txt', 'Hello content!');
    console.log('Saved mynewfile3.txt!');
    
    // Create second file
    await writeFile('mynewfile1.txt', 'This is my text');
    console.log('Created mynewfile1.txt!');
    
    // Create third file
    await writeFile('mynewfile2.txt', 'This is my text');
    console.log('Created mynewfile2.txt!');
    
    // Append content to file
    await appendFile('mynewfile1.txt', ' This is my text.');
    console.log('Updated mynewfile1.txt!');
    
    // Rename file
    await rename('mynewfile1.txt', 'myrenamedfile.txt');
    console.log('Renamed mynewfile1.txt to myrenamedfile.txt!');
    
    // Delete file
    await unlink('mynewfile2.txt');
    console.log('Deleted mynewfile2.txt!');
    
    // Replace content in remaining file
    await writeFile('mynewfile3.txt', 'This is my text');
    console.log('Replaced content in mynewfile3.txt!');
  } catch (error) {
    console.error('Error during file operations:', error);
  }
}

// Execute all operations
runFileOperations();

File Server

<!DOCTYPE html>
<html>

<body>
    <h1>Summer</h1>
    <p>I love the sun!</p>
</body>

</html>

<!DOCTYPE html>
<html>

<body>
    <h1>Summer</h1>
    <p>I love the sun!</p>
</body>

</html>

var http = require('http');
var url = require('url');
var fs = require('fs');

http.createServer(function (req, res) {
  var q = url.parse(req.url, true);
  var filename = "." + q.pathname;
  fs.readFile(filename, function(err, data) {
    if (err) {
      res.writeHead(404, {'Content-Type': 'text/html'});
      return res.end("404 Not Found");
    } 
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.write(data);
    return res.end();
  });
}).listen(8080);

localhost:8080/summer.html