title: Scala securesocial: providerId for an email registered user?
body: <p>In <em>securesocial</em> ( <a href="https://github.com/jaliss/securesocial" rel="nofollow noreferrer">https://github.com/jaliss/securesocial</a> ), you have to override the</p>
  
  <pre><code>def findByEmailAndProvider(email: String, providerId: String): Future[Option[BasicProfile]]
  </code></pre>
  
  <p>method of the <code>UserService</code> class ( <a href="https://github.com/jaliss/securesocial/blob/master/module-code/app/securesocial/core/services/UserService.scala" rel="nofollow noreferrer">https://github.com/jaliss/securesocial/blob/master/module-code/app/securesocial/core/services/UserService.scala</a> )</p>
  
  <p>But what is the <code>providerId</code> of a user who is registered through simple email registration (not using a social account) ?</p>
  
  <p>I found no description of what <code>providerId</code> is in the doc or in the code itself. My understanding is that the <code>providerId</code> is a string like "twitter", "facebook" or "google" that identifies the social network the user used to connect.</p>
  
  <p>Should I use an arbitrary string that represents my web application ("myapp" or something like that) for email registered users?</p>
  
  <p>Actually, I think I don't even understand why <code>providerId</code> is a parameter to this method. I don't see what it is used for in this context.
  If the user uses an email address to connect, isn't it already known that they're not connecting through facebook/twitter/google or whatever?</p>
  
  <p>Thanks for your help.</p>