gistfile1.rb

class MountainsController < ApplicationController
  helper_method :sort_column, :sort_direction
  before_filter :authorize, only: :edit

  def new
    @mountain = Mountain.new
  end

  def edit
    @mountain = Mountain.find(params[:id])
  end
 
  ...

  private

  ...


  def authorize
    if current_user && !current_user.admin?
      redirect_to root_url, alert: "Not authorized"
    end
  end

end