Feat: allow to disable France-Connect

Refs: #5440

app/controllers/france_connect/particulier_controller.rb

@@ -2,7 +2,11 @@ class FranceConnect::ParticulierController < ApplicationController
   before_action :redirect_to_login_if_fc_aborted, only: [:callback]
 
   def login
-    redirect_to FranceConnectService.authorization_uri
+    if FranceConnectService.enabled?
+      redirect_to FranceConnectService.authorization_uri
+    else
+      redirect_to new_user_session_path
+    end
   end
 
   def callback

app/services/france_connect_service.rb

@@ -1,4 +1,8 @@
 class FranceConnectService
+  def self.enabled?
+    ENV.fetch("FRANCE_CONNECT_ENABLED", "enabled") == "enabled"
+  end
+
   def self.authorization_uri
     client = FranceConnectParticulierClient.new
 

app/views/shared/_france_connect_login.html.haml

@@ -1,11 +1,14 @@
-.france-connect-login
-  %h2
-    = t('views.shared.france_connect_login.title')
-  %p
-    = t('views.shared.france_connect_login.description')
-  .france-connect-login-buttons
-    = link_to t('views.shared.france_connect_login.login_button'), url, class: "france-connect-login-button"
-  .france-connect-help-link
-    = link_to t('views.shared.france_connect_login.help_link'), "https://franceconnect.gouv.fr/", target: "_blank", rel: "noopener", class: "link"
-  .france-connect-login-separator
-    = t('views.shared.france_connect_login.separator')
+- if FranceConnectService.enabled?
+  .france-connect-login
+    %h2
+      = t('views.shared.france_connect_login.title')
+    %p
+      = t('views.shared.france_connect_login.description')
+    .france-connect-login-buttons
+      = link_to t('views.shared.france_connect_login.login_button'), url, class: "france-connect-login-button"
+    .france-connect-help-link
+      = link_to t('views.shared.france_connect_login.help_link'), "https://franceconnect.gouv.fr/", target: "_blank", rel: "noopener", class: "link"
+    .france-connect-login-separator
+      = t('views.shared.france_connect_login.separator')
+- else
+  <!-- FranceConnect is not configured -->

config/env.example.optional

@@ -6,6 +6,9 @@ APPLICATION_NAME="demarches-simplifiees.fr"
 APPLICATION_SHORTNAME="d-s.fr"
 APPLICATION_BASE_URL="https://www.demarches-simplifiees.fr"
 
+# Utilisation de France Connect
+# FRANCE_CONNECT_ENABLED="disabled" # "enabled" par défaut
+
 # Personnalisation d'instance - Adresses Email de l'application et téléphone
 # CONTACT_EMAIL=""
 # EQUIPE_EMAIL=""