[TYPO3-50-general] Cache problem in Extbase with reflection data

[Robert Lemke]

Hi Jungs,

Am 04.08.2009 um 12:02 schrieb Bastian Waidelich:

>> i discovered a problem with the cache of reflection data.
>
> Just to make this a bit clearer. This is about
>
> F3\FLOW3\Reflection\Service::saveToCache()
> (Tx_Extbase_Reflection_Service::saveToCache() in Extbase)
>
> There we have a call
> $this->cache->set('ReflectionData', $data);
>
> AFAIK in FLOW3 this is called once for all active packages. In Extbase
> this is probably not possible, so we need to store some extension
> identifier with the reflection data.
>
> On the other hand we might be able to add only new reflection data to
> the cache instead of overwriting anything!?

Without looking at the Extbase implementation ... here's how it  
basically
work in FLOW3:

  - on each request the reflection framework checks (very early) if  
cached
    data is available

    - if yes: load reflection data (about all classes) from cache
    - if not: reflect all classes which are _currently declared_

  - each time the reflection service's methods are called they check if
    the class in question has been reflected already

    - if yes: use the cached information already loaded earlier
    - if not: reflect the new class and return the information

  - at the end of each request the reflection framework checks if any  
new
    classes have been reflected since the data has been loaded from  
cache

    - if yes: save the new reflection data (ie. everything again)
    - if not: nothing to do

  - the overall reflection data cache entry is only flushed if  
"something
    radical" happens

  - if a single class file changes, this is detected by the file monitor
    which flushes all cache entries tagged with the class name

  - on the next run the reflection service detects which classes have  
changed
    and therefore need to be re-reflected. By this we avoid reflecting  
all
    classes again only because a few have changed.

If you haven't yet, just look at FLOW3's class \F3\FLOW2\Reflection 
\Service,
that should explain much ...

cheers,
robert