Creating a PayPal IPN Endpoint With NodeJS - ipn.ctrl.js - Processing an IPN message

ipn.ctrl.js

class IPNController { 

  static async index(req, res) {
    // Send 200 status back to PayPal
    res.status(200).send('OK');
    res.end();

    const body = req.body || {};

    // Validate IPN message with PayPal
    try {
      const isValidated = await PayPalService.validate(body);
      if (!isValidated) {
        console.error('Error validating IPN message.');
        return;
      }
      
      // IPN Message is validated!
      const transactionType = body.txn_type;
      
      switch (transactionType) {
        case 'web_accept':
        case 'subscr_payment':
          const status = body.payment_status;
          const amount = body.mc_gross;
          // Validate that the status is completed, 
          // and the amount match your expectaions.
          break;
        case 'subscr_signup':
        case 'subscr_cancel':
        case 'subscr_eot':
          // Update user profile
          break;
        case 'recurring_payment_suspended':
        case 'recurring_payment_suspended_due_to_max_failed_payment':  
          // Contact the user for more details
          break;
        default:
          console.log('Unhandled transaction type: ', transactionType);
      }
    } catch(e) {
      console.error(e); 
    }
  }

}

export default IPNController;