The content_type attribute on the Document model clashes with custom models with a content_type ForeignKey to ContentType

We have a CustomDocument model with a content_type = models.ForeignKey(ContentType, ...) field

https://github.com/wagtail/wagtail/blob/master/wagtail/documents/models.py#L170-L176 is preventing us from upgrading cleanly to 2.11+

One workaround is to rename the field and adding a db_column="content_type_id" kwarg on the definition to keep the values, and rewrite loads of code.

I would argue that content_type = models.ForeignKey(ContentType, ...) is a typical convention (and we use it with Page https://github.com/wagtail/wagtail/blob/master/wagtail/core/models.py#L748) and that we should change the property on the Document model

[gasman]

Good to hear! Renaming AbstractDocument’s content_type to mimetype (or mime_type? I think there’s precedence in Python for the single-word version, but I could be wrong…) is probably still worth doing, then, but if it isn’t a blocker for upgrading to 2.11 then we can do that in a feature release with the proper deprecation process.

[zerolab]

@gasman took more time to look at this without deadlines looming. It is indeed the inheritance precedence 🤦‍♂️ swapping things around allows adding new docs without an issue. It leaves the inline serving breakage which you had a plan for