Doctrine2 Caching of updated Elements - caching

Question

I have a problem with doctrine. I like the caching, but if i update an Entity and flush, shouldn't doctrine2 be able to clear it's cache?
Otherwise the cache is of very little use to me since this project has a lot of interaction and i would literally always have to disable the cache for every query.
The users wouldn't see their interaction if the cache would always show them the old, cached version.
Is there a way arround it?

Answer 1

Are you talking about saving and fetching a new Entity within the same runtime (request)? If so then you need to refresh the entity.
$entity = new Entity();
$em->persist($entity);
$em->flush();
$em->refresh($entity);
If the entity is managed and you make changes, these will be applied to Entity object but only persisted to your database when calling $em->flush().
If your cache is returning an old dataset for a fresh request (despite it being updated successfully in the DB) then it sounds like you've discovered a bug. Which you can file here >> http://www.doctrine-project.org/jira/secure/Dashboard.jspa

Answer 2

Doctrine2 never has those delete methods such as deleteByPrefix, which was in Doctrine1 at some point (3 years ago) and was removed because it caused more trouble.
The page http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/caching.html#deleting is outdated (The next version of the doctrine2 document will see those methods removed). The only thing you can do now is manually managing the cache: find the id and delete it manually after each update.
More advanced doctrine caching is WIP: https://github.com/doctrine/doctrine2/pull/580.

Answer 3

This is according to the documentation on Doctrine2 on how to clear the cache. I'm not even sure this is what you want, but I guess it is something to try.
Doctrine2's cache driver has different levels of deleting cached entries.
You can delete by the direct id, using a regex, by suffix, by prefix and plain deleting all values in the cache
So to delete all you'd do:
$deleted = $cacheDriver->deleteAll();
And to delete by prefix, you'd do:
$deleted = $cacheDriver->deleteByPrefix('users_');
I'm not sure how Doctrine2 names their cache ids though, so you'd have to dig for that.
Information on deleting cache is found here: http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/caching.html#deleting
To get the cache driver, you can do the following. It wasn't described in the docs, so I just traced through the code a little.
I'm assuming you have an entity manager instance in this example:
$config = $em->getConfiguration(); //Get an instance of the configuration
$queryCacheDriver = $config->getQueryCacheImpl(); //Gets Query Cache Driver
$metadataCacheDriver = $config->getMetadataCacheImpl(); //You probably don't need this one unless the schema changed
Alternatively, I guess you could save the cacheDriver instance in some kind of Registry class and retrieve it that way. But depends on your preference. Personally I try not to depend on Registries too much.
Another thing you can do is tell the query you're executing to not use the result cache. Again I don't think this is what you want, but just throwing it out there. Mainly it seems you might as well turn off the query cache altogether. That is unless it's only a few specific queries where you don't want to use the cache.
This example is from the docs: http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/caching.html#result-cache
$query = $em->createQuery('select u from \Entities\User u');
$query->useResultCache(false); //Don't use query cache on this query
$results = $query->getResult();