get thumbnail of a website

app.rb

require 'rubygems'
require 'sinatra'
#require "sinatra/reloader" if development?
require "sinatra/reloader"
require 'RMagick'
require 'watir-webdriver'
require 'base64'

# 웹사이트 썸네일 만들기. 시나트라에서 테스트완료.
#set :server, :thin

def cap(url, width, browser)
  fname="public/images/thumbs/"+url
  browser.window.resize_to(width, 1024)
  browser.driver.save_screenshot(fname+"-#{width}src.png")
  img = Magick::Image.read(fname+"-#{width}src.png").first
  img.crop!(0, 0, width, 1024)
  img.scale!(0.30)
  img.write fname+"-#{width}.png"
end

post '/ext_thumb' do
  puts Time.now
  browser = Watir::Browser.new

  url = Base64.urlsafe_encode64 params[:url]
  browser.goto params[:url]
  #browser.goto url 

  puts 'capturing...'
  cap(url, 320, browser)
  puts 'capturing...'
  cap(url, 768, browser)
  puts 'capturing...'
  cap(url, 1024, browser)
  puts 'capturing...'
  cap(url, 1440, browser)
  puts 'capturing...'


  browser.close()
  puts Time.now
  redirect "/thumb/"+url
   #"안녕!"
end
get '/thumb/:url' do
  erb :thumb
end