Login with Facebook via Rails

As a relative newbie to Rails, I'm not sure how to approach this. I am looking to add a basic "Login with Facebook" fe开发者_如何学JAVAature to a practice site I am developing. I am stuck on two fronts:

1. Most Rails plugins dealing with Facebook seem out of date or poorly documented. I've encountered Facebooker (seems to have died off from what I see) and Mini_FB (more recent, but very little documentation). I tried to install Mini_FB, but I am still very unfamiliar about working with Gems. I ran gem install mini_fb, then bundle install, and finally added gem 'mini_fb' to my Gemfile, but my server complains of a no such file to load error. Are there any other steps necessary to allow your app to use a gem?

2. I am confused by how the "Login with Facebook" feature works from an overall birds-eye view. I understand that my App ID is passed into the login feature, and I ultimately get an access token (after resubmitting with my App Secret Key and an authorization code). But how does this integrate with some kind of user system on a Rails site? Since this access code doesn't last forever, do I need to renew it periodically? Is that done by simply waiting to catch an access token error from a Graph request and redoing the entire authorization procedure?

Have you tried OmniAuth?

It supports a whole host of external providers, including facebook.

There are also a number of railscasts on it's use.

The correct order of installing a gem on your application would be first adding it to your Gemfile.rb, then running bundle install on your console. That being said, OmniAuth is probably the best path for you