This article will discuss implementing STI(Single Table Inheritance) using Devise. First, create a project.
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rails new devise-sti
Next, add devise gem in your Gemfile.
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gem 'devise'
Now, run devise commands and run migration.
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rails generate devise:install
rails generate devise User
rails db:create db:migrate
This will create a model called User. Now, in order to implement STI, two models will be inherited from the User model. Generate two models, Provider and Customer.
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touch app/models/provider.rb
touch app/models/customer.rb
Inherit these models from User.
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# app/models/provider.rb
class Provider < User
end
# app/models/customer.rb
class Customer < User
end
Implementing STI requires adding a type column in the parent model.
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rails g migration add_type_to_users type:string
rails db:migrate
In config/routes.rb, remove the following line:
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# config/routes.rb
devise_for :users
And add the following lines:
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# config/routes.rb
devise_for :customers
devise_for :providers
Generate a welcome controller.
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rails g controller Welcome index
In the newly created controller, add the following line:
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# app/controllers/welcome_controller.rb
before_action :authenticate_user!
In app/views/welcome/index.html.erb, put the following:
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# app/views/welcome/index.html.erb
<% if provider_signed_in? %>
<p>Get ready to offer your services</p>
<%= link_to 'Log out', destroy_provider_session_path, method: :delete %>
<% elsif customer_signed_in? %>
<p>What kind of service do you want?</p>
<%= link_to 'Log out', destroy_customer_session_path, method: :delete %>
<% end %>
In order to show flash messages, add these lines into app/views/layouts/application.html.erb:
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# app/views/layouts/application.html.erb
<p class="notice"><%= notice %></p>
<p class="alert"><%= alert %></p>
Finally, add the following line in app/controllers/application_controller.rb:
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# app/controllers/application_controller.rb
devise_group :user, contains: [:customer, :provider]
Now test the implementation.
Customers
Providers
There you have it! Happy implementing!