Setting up a demo user that expires after X days with devise

I made an app where a user can store data specific to its personal use case/environment. I currently set up my user with the devise gem. A user has a enum role: [:owner, :admin, :employee]

Now I would to create the possibility where a user can have 30 days access to the app (e.g. for a demo), where:

a demo_user can just log into the platform without the application having to invite him/her
the demo_user and all related data will be deleted after the demo expires (30 days after creation).

Question

How to best set this up (in a Rails way)?

I though about just adding a role and creating the logic for deletion etc. in my model, but this does not seem the most neat way to do it.

Solution

If you haven't generated the devise sessions controller, then run:

rails generate devise:controllers users -c=sessions

And in your config/routes.rb file, add:

devise_for :users, controllers: { sessions: 'users/sessions' }

That tells Devise to use the new controller you just generated. Then in your User model, add a method that tells you whether the user is expired or not:

## app/models/user.rb

class User < ApplicationRecord
  ROLES = %i[owner admin employee].freeze
  ...
  ...

  def expired?
    return false if ROLES.include? role
    (Time.now..30.days.ago) === created_at
  end
end

I'm assuming you check for demo users by checking their role, and if they're an admin owner or employee they're not a demo user.

Finally in your new sessions controller, you can remove all the methods (this will tell rails to use the devise standard ones), and insert the new create method:

class Users::SessionsController < Devise::SessionsController
  def create
    if resource.expired?
      flash[:error] = "Your account has expired"
      return redirect_to new_user_session_path
    end
    super
  end
end