Auto redirect on login page

app/controllers/employees/omniauth_callbacks_controller.rb

@@ -16,4 +16,8 @@ def default
   # TODO: Username wegspeichern
   alias keycloakopenid default
   alias saml default
+
+  def after_omniauth_failure_path_for(scope)
+    new_session_path(scope, prevent_auto_login: true)
+  end
 end

app/controllers/employees/sessions_controller.rb

@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+#  Copyright (c) 2006-2022, Puzzle ITC GmbH. This file is part of
+#  PuzzleTime and licensed under the Affero General Public License version 3
+#  or later. See the COPYING file at the top-level directory or at
+#  https://github.com/puzzle/puzzletime.
+
+class Employees::SessionsController < Devise::SessionsController
+  helper_method :auto_redirect?
+
+  private
+
+  def no_local_auth?
+    !Settings.auth.db.active
+  end
+
+  def omniauth_providers_active
+    Settings.auth&.omniauth&.map(&:second)&.map(&:active)
+  end
+
+  def single_omniauth_provider?
+    omniauth_providers_active&.one?
+  end
+
+  def auto_login_allowed?
+    return true unless prevent = params[:prevent_auto_login]
+
+    !ActiveRecord::Type::Boolean.new.deserialize(prevent)
+  end
+
+  def auto_redirect?
+    auto_login_allowed? && no_local_auth? && single_omniauth_provider?
+  end
+end

app/models/employee.rb

@@ -140,13 +140,6 @@ def providers
   end
 
   class << self
-    # Tries to login a user with the passed data.
-    # Returns the logged-in Employee or nil if the login failed.
-    def login(username, pwd)
-      find_by(shortname: username.upcase, passwd: encode(pwd)) ||
-        LdapAuthenticator.new.login(username, pwd)
-    end
-
     def employed_ones(period, sort = true)
       result = joins('left join employments em on em.employee_id = employees.id').
                where('(em.end_date IS null or em.end_date >= ?) AND em.start_date <= ?',

app/views/devise/shared/_links.html.haml

@@ -25,6 +25,12 @@
       = link_to "Mit #{provider_label} anmelden",
         public_send("#{resource_name}_#{provider}_omniauth_authorize_path"),
         method: :post,
-        class: 'btn btn-primary'
+        class: try(:auto_redirect?) ? 'btn btn-primary auto-login' : 'btn btn-primary'
       %br
       %br
+
+- if try(:auto_redirect?)
+  :coffeescript
+    $(document).on('turbolinks:load', ->
+      $('.auto-login').click();
+    )

config/routes.rb

@@ -4,7 +4,7 @@
 #  https://github.com/puzzle/puzzletime.
 
 Rails.application.routes.draw do
-  devise_for :employees, controllers: { omniauth_callbacks: 'employees/omniauth_callbacks' }, skip: [:registrations]
+  devise_for :employees, controllers: { sessions: 'employees/sessions', omniauth_callbacks: 'employees/omniauth_callbacks' }, skip: [:registrations]
   as :employee do
     get 'employees/edit' => 'devise/registrations#edit', :as => 'edit_employee_registration'
     patch 'employees' => 'devise/registrations#update', :as => 'employee_registration'

test/controllers/employees/sessions_controller_test.rb

@@ -0,0 +1,59 @@
+#  Copyright (c) 2006-2022, Puzzle ITC GmbH. This file is part of
+#  PuzzleTime and licensed under the Affero General Public License version 3
+#  or later. See the COPYING file at the top-level directory or at
+#  https://github.com/puzzle/puzzletime.
+
+require 'test_helper'
+
+class Employees::SessionsControllerTest < ActionController::TestCase
+  setup do
+    @request.env['devise.mapping'] = Devise.mappings[:employee]
+  end
+
+  test "helper auto_redirect? with only omniauth keycloadopenid active" do
+    Settings.auth.db.active = false
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = false
+    assert @controller.view_context.auto_redirect?
+  end
+
+  test "helper auto_redirect? with only omniauth saml active" do
+    Settings.auth.db.active = false
+    Settings.auth.omniauth.keycloakopenid.active = false
+    Settings.auth.omniauth.saml.active = true
+    assert @controller.view_context.auto_redirect?
+  end
+
+  test "helper auto_redirect? with only local auth active" do
+    Settings.auth.db.active = true
+    Settings.auth.omniauth.keycloakopenid.active = false
+    Settings.auth.omniauth.saml.active = false
+    refute @controller.view_context.auto_redirect?
+  end
+
+  test "helper auto_redirect? with multiple omniauth active" do
+    Settings.auth.db.active = false
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = true
+    refute @controller.view_context.auto_redirect?
+  end
+
+  test "helper auto_redirect? with local auth and single omniauth active" do
+    Settings.auth.db.active = true
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = false
+    refute @controller.view_context.auto_redirect?
+  end
+
+  test "helper auto_redirect? depending on param prevent_auto_login" do
+    Settings.auth.db.active = false
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = false
+
+    get :new
+    assert @controller.view_context.auto_redirect?
+
+    get :new, params: {prevent_auto_login: true}
+    refute @controller.view_context.auto_redirect?
+  end
+end

test/integration/employees/new_session_test.rb

@@ -0,0 +1,57 @@
+#  Copyright (c) 2006-2022, Puzzle ITC GmbH. This file is part of
+#  PuzzleTime and licensed under the Affero General Public License version 3
+#  or later. See the COPYING file at the top-level directory or at
+#  https://github.com/puzzle/puzzletime.
+
+require 'test_helper'
+
+class Employees::NewSessionTest < ActionDispatch::IntegrationTest
+  def setup
+    # We use the rack_test driver as this one does not evaluate javascript.
+    # This is required as we want to test if the page contains the necessary class attribute and javascript snippet
+    # to execute the auto login. For this the auto login redirect can't actually happen.
+    Capybara.current_driver = :rack_test
+  end
+
+  def teardown
+    # Let's restore the original driver.
+    Capybara.use_default_driver
+  end
+
+  test 'login button has auto-login class if eligible' do
+    Settings.auth.db.active = false
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = false
+
+    visit new_employee_session_path
+    assert_selector 'a.auto-login', text: 'Mit Puzzle SSO anmelden'
+  end
+
+  test 'login button does not have auto-login class if uneligible' do
+    Settings.auth.db.active = true
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = false
+
+    visit new_employee_session_path
+    assert_selector 'a', text: 'Mit Puzzle SSO anmelden'
+    assert_no_selector 'a.auto-login', text: 'Mit Puzzle SSO anmelden'
+  end
+
+  test 'page includes auto-login javascript if eligible' do
+    Settings.auth.db.active = false
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = false
+
+    visit new_employee_session_path
+    assert page.text(:all).include? "$('.auto-login').click()"
+  end
+
+  test 'page excludes auto-login javascript if uneligible' do
+    Settings.auth.db.active = true
+    Settings.auth.omniauth.keycloakopenid.active = true
+    Settings.auth.omniauth.saml.active = false
+
+    visit new_employee_session_path
+    assert page.text(:all).exclude? "$('.auto-login').click()"
+  end
+end