= Controllers

Decidim controllers are plain Rails controllers, that usually implement the other concepts that we have described in this section.

Controller classes are located in the `app/controllers/decidim/<my_module>` directory, and named: `<my_resource>_controller.rb`.

```ruby
# frozen_string_literal: true

# app/controllers/decidim/my_module/resource_controller.rb
module Decidim
  module MyModule
    class MyResourceController < Decidim::MyModule::ApplicationController

    end
  end
end
```

The admin controllers are following the `Decidim` conventions:
In the below example, you will be able to see how the forms (`ResourceForm`), commands (`CreateMyResource`, `UpdateMyResource`), queries (`Decidim::MyModule::MyResourceQuery`) and permissions (`enforce_permission_to`) can be used.

```ruby
# frozen_string_literal: true

# app/controllers/decidim/my_module/admin/resources_controller.rb
module Decidim
  module MyModule
    module Admin
      class ResourcesController < Decidim::MyModule::Admin::ApplicationController
        def index
          enforce_permission_to :read, :resource
          @resources = paginate(resources)
        end

        def new
          enforce_permission_to :create, :resource
          @form = form(ResourceForm).from_params(params)
        end

        def create
          enforce_permission_to :create, :resource
          @form = form(ResourceForm).from_params(params)

          CreateMyResource.call(@form) do
            on(:ok) do
              flash[:notice] = I18n.t("resource.create.success", scope: "decidim.my_module.admin")
              redirect_to action: :index
            end

            on(:invalid) do
              flash.now[:alert] = I18n.t("resource.create.invalid", scope: "decidim.my_module.admin")
              render action: :new
            end
          end
        end

        def edit
          enforce_permission_to :update, :resource, resource: resource
          @form = form(ResourceForm).from_model(resource)
        end

        def update
          enforce_permission_to :update, :resource, resource: resource
          @form = form(ResourceForm).from_params(params)

          UpdateMyResource.call(@form) do
            on(:ok) do
              flash[:notice] = I18n.t("resource.update.success", scope: "decidim.my_module.admin")
              redirect_to action: :index
            end

            on(:invalid) do
              flash.now[:alert] = I18n.t("resource.update.invalid", scope: "decidim.my_module.admin")
              render action: :edit
            end
          end
        end

        private
        def resources
          @resources ||= Decidim::MyModule::MyQuery.for([current_component])
        end

        def resource
          resources.find(params[:id])
        end
      end
    end
  end
end
```

== More information

- https://edgeguides.rubyonrails.org/action_controller_overview.html[Action Controller documentation]