title: How does Zapier/IFTTT implement the triggers and actions for different API providers?
body: <p>How does Zapier/IFTTT implement the triggers and actions for different API providers? Is there any generic approach to do that, or they are implemented by individual?</p>
  
  <p>I think the implementation is based on REST/Oauth, that is generic from high level to see. But  for Zapier/IFTTT, it defines a lot of trigger conditions, filters. These conditions, filters should be specific to different provider. Is the corresponding implementation in individual or in generic? If in individual, there must be a vast labor force. If in generic, how to do that?</p>