title: Authentication for Sinatra REST API app
body: <p>I'm building an API with Sinatra (using Angular for the client side and want others to have access to API) and have it also be an OAuth provider. I am wondering what the best route to take (work off existing gems or roll own solution off Warden or something).</p>
  
  <p>Have used devise and doorkeeper for authentication and oauth before with Rails, wondering what best solution for Sinatra is. </p>
  
  <p>Ideally I don't want the views or be able to extend/mod the actions of an existing solution, as I'm interacting with it purely as an API. </p>