In the last month, I’m working on two different PHP projects here at Facile.it: in the first one, which is new and still in development, I decided to adopt GitLab CI for the build, since we use GitLab CE for our Git repositories; I then created a continuous deployment pipeline for the staging environment, directly to a Kubernetes cluster, leveraging Docker Compose to make the configuration easier.
After, I decided to start migrating a previous, internal project of mine to the same approach, since it’s currently in production with a dumb approach that provokes some downtime during deployments; on the contrary, doing a rolling deployment with Kubernetes is surprisingly easy!
Abstract
Upon migrating to a new infrastructure we started experiencing cache issues after each deploy: as we refreshed pages that were updated by the new release, we didn’t see the right content for a very short period of time. Initially, we wrongly assumed that the cause of this issue was the PHP OPcache extension but, after our investigation, we understood that real path cache was the culprit.
Introduction
When I started my software developer career, I was very surprised to read the following sentence, attributed to Phil Karlton: «There are only two hard things in Computer Science: cache invalidation and naming things». In the beginning I was incredulous, because I didn’t really get the sense of these words. Not much later, I started to understand.
In the latest months I wrote multiple times, in different projects, code migrating PHPUnit toward major version 6. This upgrade is harder than the previous one, since in this version it was introduced a big breaking change: all classes got (finally!) namespaced.
This means that any usage of those classes in your project needs to be updated. It may seem a simple find & replace job, but since you need to introduce at least one use PHPUnit\Framework\TestCase line at the top of each one of your test classes, it’s a boring and a little more than trivial task; also, upgrading it in a single big jump may not be feasible or prudent, especially in the case of open source or distributed libraries, where backward compatibility and support for old PHP versions must be ensured.
A few days ago I stumbled on a strange tweet that was highlighting a controversy about scalar type hints.
After asking references about this, someone alluded to this very short video: “PHP Bits: Visual Debt” (it’s only 3 minutes, please watch it before continue reading). After that, the author of the video was dragged into the conversation, and it blew up into a big tweetstorm in the following few hours.
Like clockwork, on May we head up to Verona to attend the phpDay conference; this time it was on May 12th and 13th.
We met a lot of new people and known fellow PHP developers, and like previous years, we wanted to write down a light summary; like the previous ones, this won’t be a full “review” of the conference, but an highlight of the talks that captured most of our attention, or what we found more valuable for our everyday work.
