Models with custom PKs not called id throw errors on schema generation.

[keyz182]

When grabbing a models "ID", should probably be using model.pk - https://docs.djangoproject.com/en/dev/ref/models/instances/#the-pk-property.
A models id field is accessable through .pk, as the models PK is always accessible there. When dealing with custom PKs, this causes drf-spectacular to fall over a AttributeError: type object 'MethodCall' has no attribute 'id' error.

For example, I have a model as follows:

class MethodCall(models.Model):
    transaction = models.OneToOneField('Transaction', primary_key=True, on_delete=models.CASCADE)
    ...

As the transaction field has primary_key=True, Django doesn't generate a .id field. However transaction is still accessable via .pk.

This is where it's an issue for me:

• drf-spectacular/drf_spectacular/openapi.py

  Line 359 in bca26d3

  return self._map_model_field(get_field_from_model(field.model, field.model.id))

It may also be an issue here:

• drf-spectacular/drf_spectacular/openapi.py

  Line 399 in bca26d3

  get_field_from_model(model, model.id)

[tfranzel]

good catch! i'll have a look at it.

[tfranzel]

@keyz182 i removed all references to id. it took a moment to get it right as pk is behaving slightly different from id, but on most cases there was a more elegant solution which i didn't see before.

can you confirm the issue is resolved?

[keyz182]

@tfranzel Sorry - not been in a position to test the changes as I've had to work on other things. Thank you for the fix though, I'll let you know if/when I get a chance to test.

[tfranzel]

no problem, just trying to clean up the issue page. feel free to reopen if the fix is not sufficient.