Arvind Kushwah Web Developer and Software Consultant

Put this in config.ru :-  require 'sidekiq/web' run Rack::URLMap.new(     "/" => Rails.application,     "/sidekiq" => Sidekiq::Web )

I just add a last_sign_out_at column to my Users table and then subclassed the Devise sessions controller so I could override the destroy method to set it when the session is destroyed (user signs out): # app/controllers class SessionsController < Devise :: SessionsController def destroy current_user . update_attribute (: last_sign_out_at , Time . now ) super end end     And then in my User model I have a method to check if the user is online:   class User < ActiveRecord :: Base def online ? if current_sign_in_at . present ? last_sign_out_at . present ? ? current_sign_in_at > last_sign_out_at : true else false end end end   Also you need to tell Devise to use the new Sessions controller in your routes.  

 RewriteEngine On RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R]

I added this path in the beginning of schedule.rb:- env :PATH, '/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games'

In app/helpers/application_helper.rb :- module ApplicationHelper     def flash_class(level)         case level         when 'notice' then "alert alert-info"         when 'success' then "alert alert-success"         when 'error' then "alert alert-error"         when 'alert' then "alert alert-error"         end       end end   Somewhere in app/views/layouts/application.html.erb : <%= render 'layouts/flash_messages' %>   app/views/layouts/_flash_messages.html.erb < div > <% flash . each do | key , value | %> < div class = "<%= flash_class(key) %> fade in" > < a href = "#" data - dismiss = "alert" class = "close" >×</ a > <%= value %> </ div > <% end %> </ div > <style> .alert { padding: 8px 35px 8px 14px; margin-bottom: 18px; color: #c09853