TYPO3 Core

The cache must not be cleared automatically, because the file might be used on many pages, even with "insert record" and "show contents of this page", etc. This would be a huge complexity and can potentially kill the server, both for clearing all those caches and for regenerating the caches later on.

Instead, the caching framework should ask the caching framework to clear all cache with the tag sys_file_<uid>:

/** @var CacheManager $cacheManager */
$cacheManager = $this->getCacheManager();
$cacheManager->flushCachesInGroupByTag('pages', 'sys_file_' . $uid);

See \TYPO3\CMS\Core\DataHandling\DataHandler::processClearCacheQueue() [bottom of the function].

The integrator/developer of the site need to make sure to tag all pages that should be cleared automatically. This way he has full control over the performance impact.

Comment from Helmut Hummel in Gerrit:

The proposed CacheService works very low level, which is likely to cause troubles when changing internals.
It also works kind of "backwards" by looking at the usages of files in the moment they are changed/moved
Instead I would propose to correctly set cache tags "file_usage_<idOfFile>" for the page once the page is rendered and e.g. publicUrl is called for a file.
When doing so, we can just call ->flushByTag("file_usage_<idOfFile>") when a file is changed

Results of the discussion at the FAL sprint:
Before we can handle this in a meaningful way the Content Elements need to properly tag the page cache.

If this functionality is in place, we can then clear by tags.

Hi,

we got the same problem, hoping for a solution. The bug is accepted but there seems to be no progress since almost one year.

Can a fix still be expected?