[6.0] CMSPlugin: use Lazy Object feature

[Fedik]

Summary of Changes

Alternative to #43658

Use of PHP Lazy Object feature for plugins.
This allows to instantiate the plugin only when event is triggered, and saving some resources (time and memory).

This does not applied automatically for every plugins, the plugin service provider need to be updated to support Lazy Object.

Few thing that need to figure out:

1. Following code will trigger lazy object initialization, we need to get rid of it, somehow.
   

   joomla-cms/libraries/src/Plugin/PluginHelper.php

   Lines 234 to 236 in 2c859aa

   	if ($dispatcher && $plugin instanceof DispatcherAwareInterface) {
   	$plugin->setDispatcher($dispatcher);
   	}

2. Current use of registerListeners() need to be deprecated. There is PR for it:

• [5.3] CMSPlugin: deprecation for registerListeners #43395 Would be good if it get in to 5.x.

As next step we have to:
OR change the return type to boolean for registerListeners(),
OR replace it with new method, see the PR:

• [6.0] [RFC] CMSPlugin: Subscriber Registration Checker Interface #43657

Testing Instructions

Apply patch, and test on PHP 8.x and 8.4
The following plugins should work as before:

• schedulerunner
• tasknotification
• webauthn

Link to documentations

Please select:

• Documentation link for docs.joomla.org:
• No documentation changes for docs.joomla.org needed
• Pull Request link for manual.joomla.org: TBD
• No documentation changes for manual.joomla.org needed

I will rebase it to 6.0 later.

[laoneo]

As said already, this should be done in the DI container and not every plugin itself should implement this. Or do you see problems when the DI container does that?

[Fedik]

How to?

[laoneo]

Similar cod you have in the service provider, I would do here https://github.com/joomla-framework/di/blob/3.x-dev/src/ContainerResource.php#L160.

[Fedik]

hm, yeah, that also could work, need to check. We need it to be flexible.

But I thought that you have some ready to use solution :)

[HLeithner]

This pull request has been automatically rebased to 6.0-dev.

[voronkovich]

I would suggest to add a simple shortcut for creating lazy proxies:

// Container
public function lazy(string $class, callable $factory): callable
{
    if (PHP_VERSION_ID < 80400) {
        return $factory;
    }

    return function () use ($class, $factory) {
        return (new \ReflectionClass($class))->newLazyProxy(fn() => $factory($this));
    };
}

Then defining lazy service would look like this:

$container->share(
    'foo',
    $container->lazy(Foo::class, function($container) {
        return new Foo($container->get('bar'));
    }),
);

Full implementation you can see here:

[voronkovich]

I've created a PR with more advanced implementation: joomla-framework/di#58

[Fedik]

@laoneo That is require changes in Container code with b/c breaks (need new flags and changed method signature).
@voronkovich That implementation does not look good.

I will keep it without DI, there more important issue that need to resolve to make it work.

[laoneo]

I'm pretty sure that this can be achieved in a backwards compatible way or with a minimum of bc breaks which shouldn't affect the CMS code.