Revisit validity checks on incoming payloads
Created by: tsodring
We moved validity checks from the deserialiser class to the base class of controller as there was an issue with checking validity for updates rather than creates. Why this was an issue, I'm not sure, but we see now that an incoming payload can contain e.g. opprettetDato / opprettAv and instead of being rejected as a malformed request the incoming values are just being overwritten by the core. In this case a malformed request error should be sent back to the client.
We need to do 2 things. 1 Document where / why there is a difference in accepted values for creates as opposed to update. Fix the validity check to throw an error, like it did before.