Kevin's Blog

In case you've been hiding under a rock for the last year (and I wouldn't blame you if you were), the hot new component being bundled with Drupal 8 is a built-in layout system called "Layout Builder".  For those who've always wanted magazine-like layouts without the overhead of a heavy third-party solution like Panels, this could be your dream come true.

If you've followed my blog and/or work in the past, you'll know that I've been a big proponent of Paragraphs, and I built out the Ivan Allen College of Liberal Arts' Drupal 8 infrastructure on Paragraphs.  That was not at all a bad decision at the time - I did start that work nearly five years ago in Drupal 7 (before Drupal 8 was even released) and Layout Builder itself did not become stable until late 2019.

With everyone talking about how cool Layout Builder is, I finally sat down at the start of this year and began trying to learn how it worked, so I could see how readily I could port over some of my existing Paragraphs based layouts.  I'd put a lot of time and effort into those layouts, and I really hoped I would not have to start over from scratch.

I normally blog about technical topics here, but I'd like to step aside from that for a moment to speak my mind on conference planning.  

I recently attended an IT conference - I'll refrain from giving its name, though some of my readers will be likely to guess - and felt decidedly underwhelmed by it.  I've planned large group events in the past and thus have experience with the process from multiple angles.  Because of that, it really frustrates me to see a conference make easily avoidable mistakes.

I'll also confess that I am an introvert and quietly proud of it, so traditional networking techniques have never worked that well for me, though some definitely work better than others.  A lot of the following relates to how a series of mistakes can lead to an event that is very unwelcoming for introverts like myself.

Over the course of today and yesterday, I went through a pretty amazing journey.

A few years ago, I created a custom Drupal 7 module to generate a block of news headlines that renders in the "featured top" section of a Drupal content page.  When I ported this and other modules over to Drupal 8, I figured out the necessities and got the code working, but I'd left a large chunk of the module in Drupal 7 style or worse.  For example, I was collecting the data for these headlines through direct database queries, which even in Drupal 7 was frowned upon, but figuring out how to pull data from Paragraphs entities the right way had always proved too elusive.  On top of that, my output was generated directly within the block class's build() method, as I'd simply not had time to untangle the inner workings of Twig templates and render arrays.  I knew these techniques were not going to be terribly forward compatible, but they were purposeful quick and dirty kludges to get my sites working.

Sooner or later, it's going to happen.  You'll apply a module update or do some other under-the-hood task and the next thing you know, your Drupal 8 site is no longer responding (often called whitescreening).  While whitescreening is a good security practice (as opposed to the site spewing error messages to the browser that might reveal sensitive details), it's a royal pain when you just want your site to work and you have no idea what's wrong or where to start with fixing it.

What follows are some tips and advice that might get you back in action again without (completely) losing your sanity.

Backup, Backup, Backup (and Restore)

I'll go ahead and get this one out of the way, even though it may be too late at this point to be of any help.  In the future, always have an automatic backup generation plan in place.  The typical advice is to always make a backup before doing anything dangerous to your site, like applying patches and updates, but it's often when you don't think your action could be very dangerous that it ends up frying the whole site.

For some reason, the new internal page caching system has been the hardest thing for me to wrap my head around in Drupal 8, and dealing with it properly has eluded me for the better part of two years.  I think part of the problem is a lack of clear, understandable documentation about how it all works, so here's my attempt to sort it all out:

A Whole Host of Caching Tools

One of the more confusing parts to Drupal 8 is that there are now several ways to control caching, but the names of these components are not terribly intuitive and documentation is still kind of sparse.

External Caching Controls

Drupal 8 has an external cache control, on the Development -> Performance page, named confusingly "Page cache maximum age" (in Drupal 7, it was called "Expiration of cached pages", and the visible description included the phrase "external cache").  Contrary to what you might think, all this control does is to set an HTTP header that systems like Varnish can read and use to decide how long to cache that page.  The setting has absolutely no effect on the internal page cache.