The issue is that this method can return an AdaptiveGrainDirectoryCache, that only make sense when the builtin LocalGrainDirectory is used. It will do weird thing if used here.

But I agree that it would be nicer to be able to inject/customize the cache used here.

I see, how about if I add a new function in GrainDirectoryCacheFactory to get IGrainDirectoryCache from DI if there is one or return LRUBasedGrainDirectoryCache as a default?
this way we keep the current behavior as is but allow injecting custom IGrainDirectoryCache.
something like:

   public static IGrainDirectoryCache CreateGrainDirectoryCache(IServiceProvider services, GrainDirectoryOptions options)
   {
       var grainDirectoryCache = services.GetService<IGrainDirectoryCache>();
       if (grainDirectoryCache != null)
       {
           return grainDirectoryCache;
       }
       else
       {
           return new LRUBasedGrainDirectoryCache(options.CacheSize, options.MaximumCacheTTL);
       }
   }

@benjaminpetit any feedback about the above?

Sorry I was OOF, catching up in things... Yes I think that's better!

@benjaminpetit no worries, welcome back 🙂
I have pushed the new GrainDirectoryCacheFactory function, 'Naming things` strikes again but I did my best to come up with a name and added a summary to explain what it should do, please tell me if the name is not clear or if it can be improved 😉