Gem devise

Gem devise

1.  gem 'devise'

   gem 'bootstrap', '~> 4.0.0.alpha3'

2. Run $ bundle install

3. Add Bootstrap’s styles:  stylesheets/application.scss 
         @import "bootstrap";


4.   Run the following commands to install Devise, generate a new User model,
      and copy views for further cutomization: 
          $ rails generate devise:install

       $ rails generate devise User
       $ rails generate devise:views
       $ rails db:migrate

 5. Now restrict access to all pages of the site to authenticated users only:
     application_controller.rb  => 

class ApplicationController < ActionController::Base

 before_action :authenticate_user!

 before_action :configure_permitted_parameters, if: :devise_controller?

 protected

  def configure_permitted_parameters
   
   devise_parameter_sanitizer.permit(:sign_up) {|u| u.permit(:email,:password,:password_confirmation,:first_name,:last_name,:company_id,:user_role_id,
          :start_date,:end_date,:monthly_charge,:notes,:image,:active)}

   devise_parameter_sanitizer.permit(:account_update) {|u| u.permit(:email,:password,:password_confirmation,:first_name,:last_name,:company_id,:user_role_id,
          :start_date,:end_date,:monthly_charge,:notes,:image,:active, :current_password)}
  end
end 

6. Add this code to (Layouts/application.html.erb)

          <% if user_signed_in? %>
             Logged in as <strong><%= current_user.email %></strong>
             <%= link_to 'Edit Profile', edit_user_registration_path, :class=>'navbar-link' %> /
             <%= link_to 'Logout',   destroy_user_session_path, :class=>'navbar-link' %> / 

          <%  else  %>
            <%= link_to "Sign up", new_user_registration_path, :class=>'navbar-link' %> |
            <%= link_to "Login", new_user_session_path, :class=>'navbar-link' %>
         <%  end %>