Send webpush

webpush.js

function handleSubscription(subscription) {
  const notificationPayload = {
    notification: {
      title: 'Blogial new post',
      body: req.body.title,
      icon: 'assets/icons/icon-512x512.png'
    }
  };
  
  return webpush.sendNotification(
      subscription,
      JSON.stringify(notificationPayload)
    )
    .catch(err => {
      if (err.statusCode === 410) {
        // Error is handled, it will not throw error 500 to user.
        return Subscription.findOneAndRemove({
          _id: subscription._id
        })();
      } else {
        // Unknown error, it will throw error 500 to user.
        throw err;
      }
    });
}

exports.notification = (req, res, next) => {
  const notificationPromises = Subscription.find()
    .then(subscriptions => Promise.all(subscriptions.map(handleSubscription)));

  notificationPromises
    .then((response) => {
      res.status(200).json(response)
    }).catch(error => {
      res.status(500).json(error);
    });
};