dmkebusinessgmbh / mkvarnish Goto Github PK

You may enhance spelling of the configuration-description sentence in ext_conf_template.txt
"You can force orde disable the header direktly too."

thnx

Complete the refactoring

1.) Does this Extension support Varnish 6.1?
2.) Does this Extension wipe the cache of pages which got updated ion the Typo3 Backend automaticaly?
3.) Does this Extension support forcing caching?
3.1) Example: I have a page which Typo3 says its not cachable but it indeed is, can I somewhere force it to be cached?

Thanks for answering, would love to implement a good Varnish Cache!

The need for rn_base should be removed. Also the support for TYPO3 6.2 can be dropped.

The current approach is the following: When a clear cache command is issued in the backend the complete varnish cache is flushed. This is the first problem. The cache command can be like "cacheTag:myCacheTag" etc. and not just system, all and pages. In such a case it's bad if the complete cache is flushed.
The next problem is as soon as somebody clears the cache in PHP code with the cache manager or directly in the cache, varnish won't get updated as no clear cache command is issued.

The following approach is more low level and should be much better/more generic: A custom cache backend for Varnish should be implemented, providing methods to flush the complete cache and flush the cache by tag. This cache backend should be registered for all possible cache groups automatically if varnish is in use. This way it doesn't matter how the cache is cleared as long as the TYPO3 API is used (cache manager).

What needs to be checked: Is the cache_pages cache (or some other relevant cache) cleared at some point without using the cache manager for clearing the cache for groups? If yes, varnish should get the clear cache command, too. I'm not sure how this could be done as there seems to be no appropriate hook.

As a bonus the cache backend for varnish could also provide the methods for retrieving data from varnish. This way the cache backend could be used for other scenarios as well.