DCI with delegation instead of extension

dci_alt.rb

class User < ActiveRecord::Base
  # ... lots of persistence stuff
end

class GitHubUserProvisioner < SimpleDelegator
  def provision_with!(user_info, extra_user_hash)
    self.github_login = extra_user_hash['login']
    self.name = user_info['name']
    self.email = user_info['email']
    self.github_url = user_info['urls']['GitHub']
    self.blog_url = user_info['urls']['Blog']
    self.gravatar_id = extra_user_hash['gravatar_id']
    self.location = extra_user_hash['location']
    save!
  end 
end

# And, say, in your SessionController in your controller action

class SessionController < ApplicationController
  def create
    user = User.new
    provisioner = GitHubUserProvisioner.new(user)
    provisioner.provision_with!(*yank_oauth_stuff_off_request)
  end

  private

  def yank_oauth_stuff_off_request
    # ...
  end
end