Calibre can attempt to authenticate against your site before the tests phase of a snapshot has started. There are two methods of autentication available — basic auth, and form based login.
HTTP basic authentication is the easiest way to quickly add a username and password challenge to your site. It’s a great fit for locking your site down during development or staging.
Calibre supports basic authentication, and it's as easy as entering basic auth information into the URL of your site.
Calibre can also log into your site as if it was one of your users. Just like when automating a test suite using a tool like Selenium.
While setting up a new site, or in the settings area for each site, check "This site requires authentication".
From here, you’ll need to give Calibre a URL to find the login form, a username and password, as well as the CSS selectors that are required to find the form.
That's it! Authentication can be tricky to verify, so if you're having troubles, make sure to reach out to support for further assistance.