Guidance: Trying to create profile only accepting defined relations and ignoring all others

[hoswmph]

Hi

there is a lot of profiles out there but non of them can give me a hint how to create a profile only respecting ways with certain relations.

I want to extract all data which has route=bus set on the relation.
All my tries resulted in extractions of other ways too.

I have the following settings in setup():

    access_tags_hierarchy = Sequence {
      'bus'
    },
    access_tag_whitelist = Set {
      'bus'
    },

How ever also roads / nodes not being having the tag are extracted.

The documentation of creating the profile does not give too much guidance on the objects passed to scripts.
And debugging LUA does not help so much, as it only prints userdata.

Thanks for any help