WhatsApp Chatbot API

import express from 'express';

const app = express();
const API = 'https://api.wsapi.chat';
const HEADERS = {
  'x-api-key': process.env.WSAPI_KEY,
  'x-instance-id': process.env.INSTANCE_ID,
  'Content-Type': 'application/json'
};

app.post('/webhook', express.json(), async (req, res) => {
  const { event, data } = req.body;

  if (event === 'message' && !data.fromMe) {
    await fetch(`${API}/message/text`, {
      method: 'POST',
      headers: HEADERS,
      body: JSON.stringify({
        to: data.from,
        text: `You said: ${data.body}`
      })
    });
  }

  res.sendStatus(200);
});

app.listen(3000);