Create and Print Buffer

curl http://localhost:3000

After 100 requests within an hour, you’ll get:

node server.js

http://localhost:3000/

// Import 'jsonwebtoken' module
const jwt = require('jsonwebtoken');

// Secret key for signing and verifying JWT tokens
const secret = 'mysecretkey';

// Create a JWT token with a payload and set expiration to 1 hour
const payload = { user_id: 123, username: 'john_doe' };
const token = jwt.sign(payload, secret, { expiresIn: '1h' });

// Verify a JWT token
try {
    const decoded = jwt.verify(token, secret);
    console.log(decoded);
} catch (error) {
    console.error('Token verification failed.');
}

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// Import 'fs' module
const fs = require('fs');

// Read a file
fs.readFile('file.txt', 'utf8', (err, data) => {
  if (err) throw err;
  console.log(data);
});

// Write to a file
fs.writeFile('newfile.txt', 'Hello, Node.js!', (err) => {
  if (err) throw err;
  console.log('File written successfully.');
});

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// Import required modules
const moment = require('moment');
const _ = require('lodash');

// Get the current date and time using Moment.js
const now = moment();

// Example array of numbers
const numbers = [1, 2, 3, 4, 5];

// Calculate the sum of the array using Lodash
const sum = _.sum(numbers);

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// Import 'crypto' module
const crypto = require('crypto');

// Example password
const password = 'mypassword';

// Create SHA-256 hash of the password
const hash = crypto.createHash('sha256').update(password).digest('hex');

// Log the generated hash
console.log('Hash:', hash);

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// Import 'ws' module
const WebSocket = require('ws');

// Create WebSocket Server on port 8080
const wss = new WebSocket.Server({ port: 8080 });

// Event listener for new connections
wss.on('connection', (ws) => {
  // Event listener for incoming messages
  ws.on('message', (message) => {
    console.log('Received:', message);
    // Send a response back to the client
    ws.send('Server: ' + message);
  });
});