Cache issue-.net core 3.0-Could not load type 'System.Web.Caching.CacheItemPriority' about nhibernate-caches

[fredericDelaporte]

I have frequently seen people using SysCache2 instead of SysCache, believing SysCache2 was a later version of it. It is not the case. Granted, the naming is misleading. SysCache2 is SysCache with Sql Server dependencies, allowing it to be invalidated by events occurring on db-side. If you are not using this feature, you can use any equivalent of SysCache, which is a memory based cache.

See the documentation.

It lags a bit, RtMemoryCache is now available for .Net Core too despite what is written in the documentation. And for a pure memory cache, RtMemoryCache would be my personal choice.

[Stumblor]

@fredericDelaporte we are using syscache2 for the sql cache dependency functionality, as we have multiple apps interacting with the same database that need to inform each other of changes.

Do any of the new .netcore caching options support this feature?

[maca88]

NHibernate.Caches.SysCache2 does not support .NET Core, because System.Web.Caching was not ported. You will have to switch to one of the following caches:

• NHibernate.Caches.CoreMemoryCache
• NHibernate.Caches.CoreDistributedCache.Memcached
• NHibernate.Caches.CoreDistributedCache.Redis
• NHibernate.Caches.CoreDistributedCache.SqlServer
• NHibernate.Caches.StackExchangeRedis
• NHibernate.Caches.RtMemoryCache

The closest to SysCache2 cache is NHibernate.Caches.CoreDistributedCache.SqlServer, you can try to use it instead.

[nambir]

Hi Could you have any link which has the sample code for implementing 1.'NHibernate.Caches.CoreDistributedCache.SqlServer"
2.NHibernate.Caches.CoreMemoryCache

[maca88]

You can check how the tests are configured:

1. SqlServer
2. CoreMemoryCache

[fredericDelaporte]

Currently, no. I do not believe the underlying .Net Framework functionalities required for syscache2 have been ported to .Net Core. It was not the case in 2019, as stated here.

If they are available in .Net Core, you may PR an update to SysCache2 for supporting .Net Core, if doable through an update. Otherwise if it is available in .Net Core but through something too different for an update, you may contribute a new cache provider (preferably better named).

[fredericDelaporte]

Searching a bit the subject again, it seems syscache2 required dependency will not be ported to .Net Core, so syscache2 will remain a .Net Framework only library.

But some other functionalities like SqlDependency (available as a Platform extension) may allow to create a new provider similar to syscache2, perhaps named SqlDependencyCache by example. It would have to replace the System.Web.Caching by a pure memory cache like System.Runtime.Caching then use SqlDependency to handle the SQL Server dependencies.