License Needed in Investigation for Valid RO-Crate

[floWetzels]

Since the RO-Crate specificiation requires a license field to be specified in the root data entity (Investigation object in our case), it makes sense to validate for an existing license (via gitlab or a license file) before running the RO-Crate export. Therefore, @HLWeil and I think that such a test should be added to the validation.

Related to nfdi4plants/ARCtrl#472

[kMutagene]

I think this is a potential sensitive issue as we have heard time and time again that people are unsure whether and under what conditions they want to share data.

This is for sure easy to validate for "publishable" ARCs though, as they are intended to be accessible anyways.

However, I think making a license mandatory in "baseline" ARC validation sends the wrong signal. The ARC evolves over time, and at one point users might choose a license, but i do not think we should tell them that the ARC is invalid before that. Can this maybe be circumvented by adding a "all rights reserved" kind of license per default on export? In any case, this must be first well defined in the ARC specification and also be communicated well ahead of implementation.

cc @HLWeil @muehlhaus @Brilator

[Brilator]

Does it make a license mandatory though or is it possible to validate License == None?

I agree with @kMutagene, that it might send false signals as changing a license might not be easy / legally correct. E.g. adding CC-BY by default and at some point deciding to patent the content.