Verify a FreshBooks webhook

freshbooks-webhooks.js

const xml = require('xml');

module.exports = app => {
  //processes the webhook for when a new invoice is created
  app.post('/webhooks/new-invoice', async (req, res) => {
    try {
      // debugging
      console.log(req.body);

      const { name, verifier, object_id } = req.body;
      const xmlResponse = xml([
        {
          request: [
            { _attr: { method: name } },
            { callback: [{ callback_id: object_id }, { verifier }] }
          ]
        }
      ]);

      // debugging
      console.log(xmlResponse);

      res.set('Content-Type', 'application/xml');
      res.send(xmlResponse);
    } catch (error) {
      res.status(400).send(error);
    }
  });
};

Attempting to verify a webhook for FreshBooks from these docs.