Async cache wrong callback example

[torchello]

Hey! Seems like an example of a callback in async cache section is incorrect:

$cachedValue = $asyncCache->get('my_value', [CacheComputation::class, 'compute'])

It's not a valid callback as the compute method is not static in the example:

class CacheComputation
{
    public function compute(ItemInterface $item): string
    {
        ...
    }
}

Am I missing something or we should adjust the docs?

[torchello]

Actually, some info from this page could be added to the docs. Wdyt?
https://symfony.com/blog/new-in-symfony-5-2-async-cache-recomputing

[torchello]

Also, seems like

early_expiration_message_bus: messenger.default_bus

should be

early_expiration_message_bus: messenger.bus.default

[nicolas-grekas]

About the callback: the callable can be a pseudo-callable, where the "object" on which the method is called is actually its service name. So the doc should work. There's something called EarlyExpirationDispatcher which will turn the string into the corresponding service.

About messenger.default_bus vsmessenger.bus.default, both should work.

Did you give all this a try?

PR welcome of course!