On Friday, Google posted their annual we're getting better at JavaScript, crawling it, indexing what is behind it, and understanding JavaScript. That itself, did not get me excited, they've been messing with it since 2004, 2006 and warning us not to block it for a while.
What got me excited is a hint that Google is developing tools within Google Webmaster Tools to show common crawl issues with JavaScript on your site. The blogpost read:
To make things easier to debug, we're currently working on a tool for helping webmasters better understand how Google renders their site. We look forward to making it to available for you in the coming days in Webmaster Tools.
What common debug issues? Google detailed those also:
- If resources like JavaScript or CSS in separate files are blocked (say, with robots.txt) so that Googlebot can’t retrieve them, Google's indexing systems won’t be able to see your site like an average user. Google recommends allowing Googlebot to retrieve JavaScript and CSS so that your content can be indexed better. This is especially important for mobile websites, where external resources like CSS and JavaScript help Google's algorithms understand that the pages are optimized for mobile.
- If your web server is unable to handle the volume of crawl requests for resources, it may have a negative impact on Google's capability to render your pages. If you’d like to ensure that your pages can be rendered by Google, make sure your servers are able to handle crawl requests for resources.
- It's always a good idea to have your site degrade gracefully. This will help users enjoy your content even if their browser doesn't have compatible JavaScript implementations. It will also help visitors with JavaScript disabled or off, as well as search engines that can't execute JavaScript yet.
- Sometimes the JavaScript may be too complex or arcane for us to execute, in which case Google can’t render the page fully and accurately.
- Some JavaScript removes content from the page rather than adding, which prevents Google from indexing the content.
Soon to come!
Forum discussion at Google+ and WebmasterWorld.