Add Authentication logic

The ApplicationController provides a `current_user` method (and
helper) to access the authenticated user (if any).
The WelcomeController provides minimal logic to authenticate
against DiscourseSSO.

Current state is that one can login and logout.

Views need a lot of work.

1 files changed, 12 insertions, 0 deletions

diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 09705d1..c34b9f9 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -1,2 +1,14 @@
 class ApplicationController < ActionController::Base
+  protect_from_forgery with: :null_session
+
+  require 'sso'
+
+  before_action :current_user
+
+  protected
+
+  def current_user
+    @current_user ||= User.find_by(external_id: session[:current_user]) if session[:current_user].present?
+  end
+  helper_method :current_user
 end