items_controller.rb

class Api::V1::ItemsController < ApplicationController
  respond_to :json, :xml
  
  before_action :authenticate!
 
  def index
    respond_with Item.all
  end
 
  def show
    respond_with Item.find(params[:id])
  end
 
  def create
    respond_with Item.create(item_params)
  end
 
  def update
    respond_with Item.update(params[:id], item_params)
  end
 
  def delete
    respond_with Item.destroy(params[:id])
  end
 
  private
 
  def item_params
    params.require(:item).permit(:name, :description, :image_url)
  end
  
  def authenticate!
    authenticate_or_request_with_http_basic("Please authenticate to use the API") do |email, password|
      user = User.find_by(email: email)

      return true if user && user.authenticate(password)

      head :unauthorized
    end
  end
end