I have a spider that I am using to crawl a site. I only need javascript for one piece of my item.  So I scrape part of the site with scrapy then open the URL in selenium. While the URL is opening scrapy continues. How do I make scrapy to wait on my selenium logic to finish? 
Thanks in advance.
You can use DOWNLOAD_DELAY = 0.25 in settings.py,that the downloader should wait before downloading consecutive pages from the same website.
Another way you can use time.sleep()  for delaying spider to get response from selenium.
Scrapy and Selenium: Make scrapy wait for selenium?