Support custom assets directory for webpack resources

[rskuipers]

Sulu CMS separates its assets into assets/admin and assets/website, this means when installing Encore within a Sulu CMS install you will have to change a bunch of paths: https://docs.sulu.io/en/latest/cookbook/webpack-encore.html

This isn't my main issue, I think this is acceptable for an initial setup. But I do think we can improve what happens when you composer require a symfony bundle that provides stimulus controllers.

In the Sulu + Encore setup, the controllers.json file lives in assets/website/controllers.json. But since this path is hardcoded here:

flex/src/PackageJsonSynchronizer.php

Lines 166 to 170 in 441f671

	private function registerWebpackResources(array $phpPackages)
	{
	if (!file_exists($controllersJsonPath = $this->rootDir.'/assets/controllers.json')) {
	return;
	}

The controllers.json is not updated automatically and there's no output telling you to manually do this either. So you're left a little lost in what is still missing. Also, figuring out what to manually add in controllers.json is quite tricky since most existing UX bundles don't document this manual setup.

Before I start hacking away at a PR, any suggestions how we can solve this properly? Or do we accept that this is not configurable and those who use custom paths just have to deal with it?

Thank you in advance.

[fbourigault]

What about making this path configurable in extra.symfony of the composer.json?

[rskuipers]

That would be my suggestion as well 👍

[nicolas-grekas]

Something similar to how one can configure CONFIG_DIR?
PR welcome I suppose. Help wanted.

[smnandre]

This may require some changes in the StimulusBundle and/or framework recipes (to be checked at least)