How to Host a WhatsApp Bot on Vertra Cloud

my-bot-whatsapp/
├── src/
│   └── index.js
├── sessions/
│   └── .gitkeep
├── package.json
└── vertracloud.config

{
  "name": "my-bot-whatsapp",
  "version": "1.0.0",
  "main": "src/index.js",
  "scripts": {
    "start": "node src/index.js"
  },
  "dependencies": {
    "whatsapp-web.js": "^1.25.0",
    "qrcode-terminal": "^0.12.0"
  }
}

MAIN=src/index.js
START=npm start
VERSION=recommended

const { Client, LocalAuth, MessageMedia } = require('whatsapp-web.js');
const qrcode = require('qrcode-terminal');
const fs = require('fs');
const path = require('path');

// Session configuration with persistence
const client = new Client({
  authStrategy: new LocalAuth({
    clientId: 'bot-whatsapp',
    dataPath: path.join(process.cwd(), 'sessions')
  }),
  puppeteer: {
    // Configuration for low-memory environments
    headless: true,
    args: [
      '--no-sandbox',
      '--disable-setuid-sandbox',
      '--disable-dev-shm-usage',
      '--disable-gpu',
      '--single-process'  // Reduces memory, use with caution
    ]
  }
});

client.on('qr', (qr) => {
  console.log('QR Code received. Scan with your phone:');
  qrcode.generate(qr, { small: true });
});

client.on('ready', () => {
  console.log('WhatsApp bot successfully connected!');
});

client.on('authenticated', () => {
  console.log('Authentication successful!');
});

client.on('disconnected', () => {
  console.log('Bot was disconnected!');
});

client.on('message', async (message) => {
  try {
    if (message.from.includes('@g.us')) {
      return;
    }

    const text = message.body.toLowerCase().trim();
    const contact = await message.getContact();
    const chatName = contact.pushname || contact.name || 'User';

    console.log(`Message received from ${chatName}: ${text}`);

    if (text === '/start' || text === 'hi' || text === 'hello') {
      await message.reply(`
Welcome to the WhatsApp bot! 

Available commands:
- /menu - View menu
/info - Bot information
❓ /help - Help
 /home - Go back to the beginning
      `);
    }

    else if (text === '/menu') {
      await message.reply(`
*MENU* 

1 - Service 1
2 - Service 2
3 - Service 3

Type the number or text to request.
      `);
    }

    else if (text === '/info') {
      await message.reply(`
*BOT INFORMATION* 

Version: 1.0.0
Platform: Vertra Cloud
Developed with: whatsapp-web.js

For support, contact our team!
      `);
    }

    else if (text === '/help') {
      await message.reply(`
*HELP* ❓

Type /start to see the initial menu.
All commands start with /.

Main commands:
/menu - Menu of options
/info - Information
/help - This message
      `);
    }

    else {
      await message.reply(`
Sorry, I didn't understand your message.

Type /menu to see available options.
      `);
    }

  } catch (error) {
    console.error('Error processing message:', error);
    message.reply('Sorry, an error occurred while processing your message.');
  }
});

client.on('error', (error) => {
  console.error('Client error:', error);
});

process.on('unhandledRejection', (reason, promise) => {
  console.error('Unhandled Promise rejection:', reason);
});

client.initialize();