Today, I received a request to dynamically check the HTTP response code of every sub-category link on the site’s navigation menu using synthetic test agents. Categories included Shoes, Home, Beauty, Kids, Women, Men, etc. and sub-categories included more specific links such as Boots, Sandals, Slippers, Trainers, etc. This client wanted to set these tests up under a third-party service, so the options were limited to either (1) creating a single page measurement for each sub-category link, or (2) creating a multi-page script to test all of the sub-category links. So, any sort of web crawling or web scraping service was not an option. Setting up single page measurements would not work since this client had a dynamic sub-category list that would change over time. So, that left me with the multi-page script option. The third-party does support some Selenium commands in their multi-step synthetic scripts, which is quite fortunate.
However, the provider’s multi-step synthetic scripts stop the test completely when there is one failure. So if the second sub-category link returns a 404 code, then the entire script will stop and not test the remaining sub-categories. Crawling through each sub-category link was not an option with this configuration. So, I had to think outside of the box to fulfill their requirements.
Since the customer is only interested in the HTTP response code, the request was substantially simpler than I originally thought. For a concept test, I started with testing all of the sub-category links for only one category page. The customer wanted a high-level pass/fail response for each category, and then detailed failure messages for each sub-category link in the console log. So, I wrote a small snippet of JavaScript to pull all of the sub-category links into a list, and then asynchronously request each URL through an XHR request for the response code. This snippet also included a separate section to print a custom message to the page that had the number of failures and a particular CSS class if there were any failures. The synthetic script opened the category URL, ran the JavaScript snippet, and then checked for that particular CSS class to pass/fail the script as a whole.
// Pull list of sub-category links
// Get the HTTP code for each link
// Print a custom message to the page
Once that concept test was up and running successfully in their third-party software, I was able to wrap up the project by expanding to other category pages. Essentially, this client occassionally changed their category URLs or added a new category (such as a holiday or Mother’s Day category) so those needed to be tested dynamically as well. I had already built a piece to test all of the sub-category links, but as mentioned before the test would stop completely if a link on one of those category pages failed. So instead I added a separate JavaScript snippet to map each category link to a minute of the hour, and then the test would run once per minute constantly. There would be slightly fewer tests per hour run on a couple of the category links, but the client’s requirements included testing each category page every 10 minutes, so this was sufficient.