Implement Oauth2 together with own app
<p>I have an application using Devise. And I want to use OAuth2 in my API for authentication.</p>

<ul>
<li>Is it possible to implement OAuth2 without using Doorkeeper, OmniAuth etc?</li>
<li>How could I implement OAuth2 in my app because it must provide 'client_id', 'client_secret', :site?</li>
</ul>