How to redirect to a 404 in Rails?

readme.md

How to redirect to 404 in Rails 5

• Code bellow shows how to redirect to 404 page, when your application use friendly_id gem.
• Use find method instead of find_by_id will work well and prevent of throwing errors.

Thanks to

• http://stackoverflow.com/a/4983354/66493
• https://gist.github.com/nunommc/ee3c2596b1acbce50818

application_controller.rb

# app/controllers/application_controller.rb

class ApplicationController < ActionController::Base
  
  def not_found
    raise ActionController::RoutingError.new('Not Found')
  rescue
    render_404
  end

  def render_404
    render file: "#{Rails.root}/public/404", status: :not_found
  end
  
end

posts_controller.rb

# app/controllers/posts_controller.rb

class PostsController < ApplicationController
  before_action :set_post, only: [:show, :edit, :update, :destroy]
  
  def index
    @post = Post.all
  end

  def show
  end

  def new
    @post = Post.new
  end

  def edit
  end
  
  private
    # Use callbacks to share common setup or constraints between actions.
    def set_post
      # very important to have `exists?`
      # read more => http://api.rubyonrails.org/classes/ActiveRecord/FinderMethods.html#method-i-exists-3F
      @post = Post.friendly.find(params[:id]) or not_found
    end
end

AhmedNadar

The sentence does not work:
@post = Post.friendly.find(params[:id]) or not_found
change by:
@post = Post.friendly.find(params[:id]) rescue not_found

Regards