Track authentication events from devise (warden)

authentication_events.rb

# this gets called every time a user is authenticated
# either via an actual sign in or through a cookie
Warden::Manager.after_authentication do |user,auth,opts|
  auth.params.has_key?('user') ? 'trigger direct sign in' : 'trigger cookie sign in'
end

# this gets called every time a user is fetched from session.
# happens on every request!
Warden::Manager.after_fetch do |user,auth,opts|
  'trigger user request'
end

# this gets called every time a user performs a sign out.
Warden::Manager.before_logout do |user,auth,opts|
  'trigger sign out'
end

# this gets called every time a request fails due to lacking authentication
Warden::Manager.before_failure do |env, opts|
  # parse params
  # Rack::Request.new(env).params

  # authentication failed:
  # opts == {:scope=>:user, :recall=>"devise/sessions#new", :action=>"unauthenticated", :attempted_path=>"/users/sign_in"}

  # redirect as a user is required
  # opts == {:scope=>:user, :action=>"unauthenticated", :attempted_path=>"/"}

  'trigger sign in failed' if opts.has_key?(:recall)
end