title: Magento external access
body: <p>I have a Shopify App and am willing to port it to Magento.
  Given a running Magento ecommerce URL, is there a way to:</p>
  
  <ul>
  <li>Retrieve a [token / OAuth] to access the data from Magento using a RESTFul / SOAP / Whatever way?</li>
  <li>Using Magento exposed API, register an external URL as a webhook endpoint to receive notifications whenever an Order gets created or when a Product gets created / updated / destroyed?</li>
  <li>If both things are possible, how do you take care of all those different Magento versions?</li>
  </ul>