enum.EnumField seems not to work in Django 1.10

[georgekpg]

In django 1.10 get_deferred_fields routine from django.db.models.base counts all enum.EnumField fields in a model as deferred fields. As a result it passes update_fields in save_base routine and raises "Cannot force an update in save() with no primary key" exception when I attempt to save new model instance.

In django 1.9.9 the same model works okay. I am using django-enumfield==1.3b2 installed with pip

[mandery]

I have the exactly same issue.

Creating and saving an instance of a model with an EnumField leads to ValueError("Cannot force an update in save() with no primary key.").

[Bartvds]

This is blocking some application upgrades.

Might have something to do with this warning you get using django-enumfield 1.3b2 in django 1.9.x: RemovedInDjango110Warning: SubfieldBase has been deprecated. Use Field.from_db_value instead.

[woodcoder]

I just found PR #37 which discusses this in more detail...

[servomac]

I have a similar problem using Django 1.10.2 and django-enumfield 1.2.1:

  File "/usr/local/lib/python3.5/dist-packages/django_enumfield/enum.py", line 6, in <module>
    from django_enumfield.db.fields import EnumField
  File "/usr/local/lib/python3.5/dist-packages/django_enumfield/db/fields.py", line 8, in <module>
    class EnumField(six.with_metaclass(models.SubfieldBase, models.IntegerField)):
AttributeError: module 'django.db.models' has no attribute 'SubfieldBase'

[temclaugh]

This is similar to this issue jpwatts/django-positions#49
A temporary fix is to overwrite the get_deferred_fields method on any model with an EnumField, like this:

def get_deferred_fields(self):
        enum_fields = filter(lambda x: isinstance(x, enum.EnumField), ThisModel._meta.fields)
        enum_field_names = set(funcy.pluck_attr('name', enum_fields))
        deferred_set = super(ThisModel, self).get_deferred_fields()
        return {f for f in deferred_set if f not in enum_field_names}

[Bartvds]

Pinging @lundberg @andreif to ask if this package is dead? What do you use for Django 1.10 at 5monkeys?

[georgekpg]

Bartvds, I at last ended on using this branch https://github.com/i2biz/django-enumfield/tree/jbzdak/django110. It works ok with django 1.10. Only thing that I lost was validating transitions, but I managed to rewrite it myself as standalone function.

[andreif]

@Bartvds Hi, we just need a project where we could continue to develop the package. Currently I am working with 1.10 one and soon will need to do something about enumfield.

Preliminary plan is to merge enum34 branch and add support for 1.10-1.11.

[sinarezaei]

@georgekpg Hi, can you please explain how did you manage to rewrite validating transitions, I'm currently having the same issue.

[georgekpg]

@sinarz, my implementation is based upon django-simple-history, it helps me to detect changed fields.

from simple_history.models import HistoricalRecords
from django_enumfield import validators as enum_validators

def validate_enum_transitions(obj,fields):
    try:
        prev = obj.history.most_recent()
    except:
        return
    
    for fname in fields:
        try:
            f = obj._meta.get_field(fname)
        except:
            continue
        if hasattr(f,'enum'):
            enum_validators.validate_valid_transition(f.enum,f.value_from_object(prev),f.value_from_object(obj))

And I can call this in clean method implementation of my model

class Ticket(models.Model):
    status = enum.EnumField(TicketStatus, default=TicketStatus.DRAFT,verbose_name=_('Ticket status'))
    history = HistoricalRecords()

    def clean(self):
        validate_enum_transitions(self,('status',))

[sinarezaei]

Thanks @georgekpg , nice implementation. I'll give it a try.

[ashkulz]

#43 works for me as a drop-in replacement in Django 1.11, original patch was from @kjagiello

[Swamii]

Please try version 1.4rc1

[Swamii]

1.4 has been released. Please reopen if it doesn't work for any reason