fix(utils): raise exception on failing creation of object

[b1rger]

No description provided.

[gythaogg]

Tested, works! Definitely prefer this implementation Could not create <field name> from <input value> to the previous error - None type object has no attribute pk.

This error message is of course valid when an actual error occurs while trying to create an object from a URI (assuming we have an importer defined)

But in this case when a user enters a non URI string or if the field is not setup to create objects from external sources - as I guess is the case with Profession in Discworld, could we maybe also inform that it is not possible to create new values from any string and it is currently only possible from URIs, if that is supported? Or in the case that there is no importer defined, could we disable the Create option?

[b1rger]

But in this case when a user enters a non URI string or if the field is not setup to create objects from external sources - as I guess is the case with Profession in Discworld, could we maybe also inform that it is not possible to create new values from any string and it is currently only possible from URIs, if that is supported? Or in the case that there is no importer defined, could we disable the Create option?

Hm, currently the GenericImporter is a fallback for the case when no Importer is defined for a model, which means there is always in Importer defined. I'd say the Exception message is generic enough to be true for any case (be it a URL that could not be parsed or a non-url string) and we should probably look into ways to enable creating model instances from strings.