KNP Labs

29/05/2026

Rewind ⏪ Design Patterns #14
Alrighty, it's the FINAL chapter of the Design Patterns tutorial! We override a core Symfony service by writing just *one* class, thanks to the decorator pattern & the #[AsDecorator] attribute. Plus we show where you can find decorators in the wild.

In Symfony, decoration has a secret super-power: it allows us to customize nearly *any* service inside of Symfony. Woh

28/05/2026

Rewind ⏪ Design Patterns #13
How can you use the decorator pattern with Symfony's service container? Let's do it the "manual" way first: via a service alias from the interface and some clever wiring.

We just implemented the decorator pattern, where we basically wrapped the original "XpCalculator" in a warm hug with our "OutputtingXpCalculator". Then... we quietly slipped *that* into the system in place of the *original*... without anyone else - like "XpEarnedObserver&quo...

27/05/2026

Rewind ⏪ Design Patterns #12
Time for the *final* design pattern... and maybe my favorite! It's the decorator pattern! Let's define it and get it set up inside our app.

One more design pattern to go! And honestly, I think we may have saved the best for last. It's the *decorator* pattern

26/05/2026

Symfony upgrades do not have to be scary 😌
Deprecations are your roadmap:
Fix warnings in 7.4 → upgrade safely to Symfony 8 🚀
0 deprecations = no surprises.

Symfony upgrades do not have to be stressful. Thanks to Symfony's deprecation system, you can fix future breaking changes before upgrading

25/05/2026

Symfony form tip 💡
`form_row()` renders everything.
`form_widget()` renders just the field itself.
Need full control?
Render the label, widget, errors, and help text separately 🎨

22/05/2026

Rewind ⏪ Design Patterns #11
Happy Friday! Celebrate by dispatching fresh waffles & an extra cup of coffee to anyone that wants to listen. Yes, this was a Pub-Sub pattern joke...

We *are* able to run code right *before* a battle starts by registering what's called a "listener" to "FightStartingEvent". As you can see, a listener can be any function... though what we see here is a bit less common

21/05/2026

Rewind ⏪ Design Patterns #10
Time for the pub-sub pattern! Which... is maybe more of a variation on the observer pattern. Let's figure out the difference and see how we can dispatch & listen to an event directly in PHP.

The next pattern I want to talk about maybe *isn't* its own pattern? In reality, it's more of a *variation* of the observer pattern. It's called "pub/sub" or "publish-subscribe"

20/05/2026

SymfonyCasts Snippets:
Ahoy matey ⚓
YAML anchors & aliases let you define a piece of config once, then reuse it wherever you need it. Less duplication, more reuse, and your config files stay shipshape ⛵

19/05/2026

Upgrading to Symfony 8 #5
With the "hard" work behind us, the actual jump from Symfony 7.4 to 8.0 should be pretty easy. Plus, we'll check out a nifty Composer command afterward to confirm we have no outdated 😉 packages.

Symfony 7.4? Check

15/05/2026

Rewind ⏪ Design Patterns #9
Such a fun way to wrap up the observer pattern! We see how this is implemented - in real life - in a Symfony app. This includes tags, autoconfiguration, a compiler pass and a method call. Woh!

We've implemented the Observer Pattern! The "GameApplication" is our subject, which notifies all of the observers... and we have *one* at the moment: "XpEarnedObserver". Inside "GameCommand", we connected all of this by *manually* instantiating the observer and "Xp...