ReactPHP, reloading templates impossible?

[jdeepwell]

I am trying to use Twig in a ReactPHP project, but it seems they are fundamentally incompatible. If I understand the docu and the code correctly, Twig assumes that for each request the PHP engine gets "reset" so that all loaded classes are gone again – which in ReactPHP of course is not the case.

I think this is the reason why I am unable to get Twig to reload my templates when I change them – I always need to restart my ReactPHP app, which during development of course is a no-go (it's near impossible to write and improve on templates that way).

I am down to creating a new Environment instance for each request and setting cache=false and auto_reload=true - but the generated classes are not re-generated when I change a template. The name of the generated class does include a hash but that does hash not depend on a timestamp or similar and therefore once the class exists inside the ReactPHP app's code it will not go away and of course cannot be "updated".

Am I missing something fundamental here or is Twig really not usable with ReactPHP in a way that lets me re-load changed templates without re-starting my app?

[GromNaN]

The name of the generated class does include a hash but that does hash not depend on a timestamp or similar and therefore once the class exists inside the ReactPHP app's code it will not go away and of course cannot be "updated".

Something I don't understand: how does it work when you modify a PHP class in your project? The server has to be restarted, because you can't redefine a class that's already been defined.

[jdeepwell]

When I change code in the project a do have to restart the app. But code changes (in my experience) are much less "interactive" than design changes. When I am working on the design of a page it is cumbersome to have to restart the app for each small change I make to view the result.

I was hoping that there was some "debug" mode of Twig in which the generated classes get an additional part in the class name that changes whenever the template file changes. That would of course fill up PHP with classes, but that would IMHO be acceptable during the design phase.

[GromNaN]

You can call Environment::removeCache($templateName) that was introduced by #4338 for this purpose.

[jdeepwell]

Thx for that hint! 🙏

That works at least with basic templates. For extends (template inheritance) it unfortunately only works for the detail (the extending) template, not for the base (the extended) template. Even if I call removeCache() for both, the base template does not get reloaded.

So if I have e.g. a base.twig and a detail.twig that extends base.twig, calling removeCache() for both only reloads the detail.twig 😥

(or at least the newly loaded base.twig does not get used)