http://stackoverflow.com/questions/7628952/omniauth-facebook-expired-token-error
tapメソッドというのを初めて知った。
class SessionsController < ApplicationController def create auth = request.env["omniauth.auth"] user = User.find_by_provider_and_uid(auth["provider"], auth["uid"]).tap do |u| u.update_attributes(:token => auth["credentials"]["token"]) if u end || User.create_with_omniauth(auth) session[:user_id] = user.id redirect_to root_url, :notice => "Signed in!" end