session_expired_popup_message_v2.diff - Redmine

     RedmineApp::Application.routes.draw do
       root :to => 'welcome#index', :as => 'home'
       get 'session_heartbeat', :to => 'application#session_heartbeat'
       match 'login', :to => 'account#login', :as => 'signin', :via => [:get, :post]
       match 'logout', :to => 'account#logout', :as => 'signout', :via => [:get, :post]

     $(document).ready(setupAjaxIndicator);
     $(document).ready(hideOnLoad);
     $(document).ready(addFormObserversForDoubleSubmit);
     function SessionHeartbeat() {
         $.ajax( {
                 url: '/session_heartbeat',
                 success: function(data) {
                     if(data.expired) {
                         alert(data.message);
+                    }
                     else if(data.remain > 0) {
                         setTimeout(SessionHeartbeat, data.remain);
+                    }
+                }
+            }
         );
+    }

       include Redmine::MenuManager::MenuController
       helper Redmine::MenuManager::MenuHelper
       def session_heartbeat
         remain = 0
         if Setting.session_lifetime? && session[:ctime]
           remain = (Setting.session_lifetime.to_i * 60) - (Time.now.utc.to_i - session[:ctime].to_i)
         end
         if Setting.session_timeout? && session[:atime]
           if remain > 0
             remain = [remain, (Setting.session_timeout.to_i * 60) - (Time.now.utc.to_i - session[:atime].to_i)].min
           else
             remain = (Setting.session_timeout.to_i * 60) - (Time.now.utc.to_i - session[:atime].to_i)
           end
         end
         if session_expired? || remain <= 0
           render json: { expired: true, message: l(:error_session_expired) }
         else
           render json: { expired: false, remain: (remain * 1000) }
         end
       end
       def session_expiration
         # Skip session heartbeat
         return if ((params[:controller] == 'application') && (params[:action] = 'session_heartbeat'))
         if session[:user_id]
           if session_expired? && !try_to_autologin
             reset_session

         unless User.current.pref.warn_on_leaving_unsaved == '0'
           tags << "\n".html_safe + javascript_tag("$(window).load(function(){ warnLeavingUnsaved('#{escape_javascript l(:text_warn_on_leaving_unsaved)}'); });")
         end
         if User.current && (!User.current.anonymous?) && (Setting.session_timeout || Setting.session_lifetime)
           lifetime = Setting.session_lifetime ? Setting.session_lifetime.to_i : 0
           timeout = Setting.session_timeout ? Setting.session_timeout.to_i : 0
           timeout = lifetime if lifetime > 0 && lifetime < timeout
           unless timeout == 0
             tags << "\n".html_safe + javascript_tag("setTimeout(SessionHeartbeat, #{timeout * 60000});")
           end
         end
         tags
       end

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