[TYPO3-core] RFC #15937: Bug: [Caching framework] Improve error message if no frontend was defined for core caches

[Ernesto Baschny [cron IT]]

Christian Kuhn schrieb am 08.10.2010 19:59:
> Hey,
> 
> On 10/08/2010 04:36 PM, Christian Kuhn wrote:
>> Problem:
>> With issue #15389 we un-hardcoded the cache frontends for core caches.
>> This now leads to an error if own core caches are defined and the
>> frontend setting is missing. t3lib_div::makeInstance will then get null
>> as frontend class and just spits error "Class not found", without more
>> infromation on what exactly went wrong. This makes this issue hard to
>> track down.
>>
>> Solution:
>> Throw a more meaningful error message in t3lib_cache if frontend
>> definition is missing for core caches.
> 
> Seems that even some extensions do not come with proper frontend
> definitions, see for instance http://bugs.typo3.org/view.php?id=15940
> 
> Thus, I've moved the exception from core cache handling to the cache
> factory. This will now catch all frontends which have not been defined
> in $GLOBALS['TYPO3_CONF_VARS']['SYS']['caching']['cacheFrontends'].

If extensions used to work with 4.4, they will then fail with an
exception in 4.5? That is a "no go" I would say, even if the exception
provides a nice message of what is wrong.

Better would be to fallback to "t3lib_cache_frontend_VariableFrontend"
in case no frontend is defined for a specific caching setup.

Or maybe I have misunderstood the issue?

Cheers,
Ernesto