facebook_connect_rspec.rb

describe "Facebook Connect Authentication" do
  
  it "should create a new user in the system when the Facebook Connect cookies are set" do
    response = request(url(:home), :cookie=>facebook_cookies)
    user = User.first(:facebook_id=>facebook_params[:user])
    user.should_not be_nil
    user.should be_valid
  end
  
end

# Some helper methods to reduce a bunch of redundancy
# probably could use some refactoring but hey... 
def facebook_params
  {
    :user => 123456,
    :session_key => Digest::MD5.hexdigest('this is a fake session key'),
    :ss => Digest::MD5.hexdigest('this is a fake session secert'),
    :expires => (Time.new+3600).to_i
  }
end # facebook_params

def facebook_key
  Merb.config.fetch(:facebook_key, nil)
end # facebook_key

def facebook_secert
  Merb.config.fetch(:facebook_secret, nil)
end # facebook_secert

# Generate the Facebook signature according to the Facebook Connect documentation
def generate_signature
  Digest::MD5.hexdigest(facebook_params.to_mash.sort.map{|k,v| "#{k}=#{v}"}.join)
end # generate_signature

def facebook_cookies
  [
    "#{facebook_key}_user=#{facebook_params[:user]}",
    "#{facebook_key}_session_key=#{facebook_params[:session_key]}",
    "#{facebook_key}_expires=#{facebook_params[:expires]}",
    "#{facebook_key}_ss=#{facebook_params[:ss]}",
    "#{facebook_key}=#{generate_signature}",
  ]
end #facebook_cookies

facebook_strategy.rb

class FacebookConnectStrategy < Merb::Authentication::Strategy
  # Some convenience functions
  include FacebookConnect::Mixins
  
  def run!
    Merb::logger.debug("Authenticating Facebook: #{facebook_id}")
    unless user = User.first(:facebook_id => facebook_id)
      # create a new user record for the facebook user.
      user = User.new
      user.facebook_id = facebook_id
      user.first_name = "Facebook"
      user.last_name = "User"
      user.password = user.password_confirmation = Digest::MD5.hexdigest(facebook_id.to_s + Merb::Config.fetch(:facebook_secret, Time.now.to_i))
      user.login = facebook_id.to_s
      user.save
    end # unless user
    valid_facebook_user? ? user : nil
  end # run!
end # FacebookConnectStrategy