require 'sinatra' require 'tilt/erb' set :public_folder, 'public' class CorgBotApp < Sinatra::Base get '/' do extensions = ['.png', '.jpg', '.jpeg', '.gif'] images = Dir.entries('public/images').delete_if { |x| extension = x[-4, 4] !extensions.index(extension) } corgi = images[rand(images.length)] erb :index, :locals => { :corgi => corgi } end end