gistfile1.rb

class YourModel < ActiveRecord::Base
  include Rakismet::Model

  # Create Validator which will hit the Akismet API
  class SpamValidator < ActiveModel::Validator
    def validate(record)
      return true unless record.spam? # record.spam? will hit the Akismet API
      record.errors[:base] << "Spam message detected."
    end
  end

  attr_accessible :id, :user_ip, :user_agent, :referrer, :full_name, :email, :message, :created_at, :updated_at
  # Re-map attributes for Rakismet
  rakismet_attrs author: :full_name, author_email: :email, content: :message
  # Run the validator for our message content
  validates :message, presence: true, spam: true

  # Set Client attributes from the request which are required for Akismet's API
  def request=(request)
    self.user_ip = request.remote_ip
    self.user_agent = request.env['HTTP_USER_AGENT']
    self.referrer = request.env['HTTP_REFERER']
  end
end