Symfony2.1 - HWIOAuthBundle and google oauth authentication
As beliveyourdream says... HWIOAuth does NOT provide you automatic user registration. You need to create your own user provider and use that. I suggest you go with FOSUserBundle as it does most of the job and it is pretty well integrated in HWIOAuth. For how to set up (as it is a bit of work to do on connecting them), please use this Gist. It does setup your application with both user registration using data from PROVIDERS (gacebook, google, github, etc.) and account connection (an already registered user may connect his/her account with accouns from PROVIDERS). Also, upon creation/connection, the users will be able to connect to your site with the PROVIDERS' credentials (duh... it's OAuth, after all).
Sadly, HWIOAuthBundle doesn't handle automatic registration by default. If you want to login now you'll have to create the user manually.