Lettable-based Controller Example

widgets_controller.rb

class WidgetsController < ApplicationController
  let(:widgets) { Widget.all }
  let(:widget) { widgets.find_or_initialize_by id: params[:id] }
  
  def new
    render :form
  end
  
  def edit
    render :form
  end
  
  def create
    save
  end
  
  def update
    save
  end
  
  def destroy
    widget.destroy
    redirect_to widgets_url, notice: 'Widget was successfully destroyed.'
  end
  
  private
  
  def save
    if widget.update secure_params
      redirect_to widget, notice: 'Widget was successfully saved.'
    else
      render :form
    end
  end
  
  def secure_params
    params.require(:widget).permit :name
  end
end