Facets from an object graph

Hi guys,
I have an object whose attributes are made of another compound objects rather than primitive strings or integers and I need to do facets from them.
In the official documentation , making facets from date attribute of the NewsDocument , filtering by year is done with :

hippofacnav:facets

  • myproject:brand
  • myproject:date$year

I need something similar , but for a compound object like :
Event -> TimePeriod -> Calendar

Following the previous example , I tried this without results :
hippofacnav:facets

  • myproject:TimePeriod$Calendar$year

Is there a way to do that?

Unfortunately faceted navigation only works on direct properties of documents, not of compounds. If you have a reason why you want/need to use a compound for these properties, you can use a derived data function to set them in “hidden” properties on the document node.

Thanks Jasper, will try to use derived data for it.