Make it easier to override the RelatedFieldWidgetWrapper in admin.

[rm_]

My use case is to pass some initial data to new model instances added via the add-related link. This should be trivial leveraging ModelAdmin.get_changeform_initial_data but I can't find an easy way to pass the query string to the RelatedFieldWidgetWrapper widget in order to be rendered in the template.

Possible plan:

• extract related field widget creation from BaseModelAdmin.formfield_for_dbfield into an get_widget_for_related_field helper
• create a get_url_params helper in RelatedFieldWidgetWrapper

Both looks like cleanups that have their own merit.

[rm_]

WIP patch for discussion here ​https://github.com/django/django/pull/12937

[Mariusz Felisiak]

Thanks for this ticket, however you use case looks quite niche, I don't see a wide use of new hooks. raw_id_fields should not be customized, IMO. If you really need to use the same mechanism you can create a custom widget (without using raw_id_fields).

[rm_]

@felixxm I'm a bit puzzled. This is has nothing to do with raw_id_fields but with the changeform popup and the related widget wrapper :) I won't object the niche use case though but what I'm doing here is making easier to override the default widget which is what you are suggesting :)

[Mariusz Felisiak]

True, sorry, forget what I said about raw_id_fields. Nevertheless I still think you should be able to handle this with a custom widget.

[rm_]

Sorr for the late response but I didn't get any notification. The plan is to use a custom widget, the patches here are 1) a way to use a custom widget without overriding the full BaseModelAdmin.formfield_for_dbfield becasue RelatedFieldWidgetWrapper is hardcoded 2) extract a simpler method in RelatedFieldWidgetWrapper to override (that also matches what the other related widgets are doing). Anyway I don't want to insist, thanks anyway for the review.