RenameField with django 2.0: AttributeError: 'ManyToManyRel' object has no attribute 'field_name'
527 views
Skip to first unread message
edigi...@arpae.it
Dec 4, 2017, 8:19:50 AM12/4/17
to Django users
With Django==2.0, a RenameField on a model which has a reverse many to many relationship raises an exception:
AttributeError: 'ManyToManyRel' object has no attribute 'field_name'
The same migration with Django==1.11 terminates successfully.
Migrations are automatically generated by `manage.py makemigrations`.
Am I missing something?
Below the code and the commands to reproduce the problem:
# myapp/models.py
from django.db import models
class ModelA(models.Model):
new_name = models.IntegerField()
class ModelB(models.Model):
model_as = models.ManyToManyField('ModelA')
# myapp/migrations/0001_initial.py
from django.db import migrations, models
class Migration(migrations.Migration):
initial = True
dependencies = [
]
operations = [
migrations.CreateModel(
name='ModelA',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('old_name', models.IntegerField()),
],
),
migrations.CreateModel(
name='ModelB',
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
('model_as', models.ManyToManyField(to='myapp.ModelA')),
],
),
]
# myapp/migrations/0002_auto_20171204_1012.py
from django.db import migrations
class Migration(migrations.Migration):
dependencies = [
('myapp', '0001_initial'),
]
operations = [
migrations.RenameField(
model_name='modela',
old_name='old_name',
new_name='new_name',
),
]
$ ./manage.py migrate
Operations to perform:
Apply all migrations: admin, auth, contenttypes, myapp, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
Applying auth.0001_initial... OK
Applying admin.0001_initial... OK
Applying admin.0002_logentry_remove_auto_add... OK
Applying contenttypes.0002_remove_content_type_name... OK
Applying auth.0002_alter_permission_name_max_length... OK
Applying auth.0003_alter_user_email_max_length... OK
Applying auth.0004_alter_user_username_opts... OK
Applying auth.0005_alter_user_last_login_null... OK
Applying auth.0006_require_contenttypes_0002... OK
Applying auth.0007_alter_validators_add_error_messages... OK
Applying auth.0008_alter_user_username_max_length... OK
Applying auth.0009_alter_user_last_name_max_length... OK
Applying myapp.0001_initial... OK
Applying myapp.0002_auto_20171204_1012...Traceback (most recent call last):
File "./manage.py", line 15, in <module>
execute_from_command_line(sys.argv)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/core/management/__init__.py", line 371, in execute_from_command_line
utility.execute()
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/core/management/__init__.py", line 365, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/core/management/base.py", line 288, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/core/management/base.py", line 335, in execute
output = self.handle(*args, **options)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/core/management/commands/migrate.py", line 200, in handle
fake_initial=fake_initial,
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/db/migrations/executor.py", line 117, in migrate
state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/db/migrations/executor.py", line 244, in apply_migration
state = migration.apply(state, schema_editor)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/db/migrations/migration.py", line 122, in apply
operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/db/migrations/operations/fields.py", line 304, in database_forwards
to_model._meta.get_field(self.new_name),
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/db/backends/sqlite3/schema.py", line 81, in alter_field
any(r.field_name == old_field.name for r in model._meta.related_objects)):
File "/home/edg/src/example/env/lib/python3.6/site-packages/django/db/backends/sqlite3/schema.py", line 81, in <genexpr>
any(r.field_name == old_field.name for r in model._meta.related_objects)):
AttributeError: 'ManyToManyRel' object has no attribute 'field_name'
$ pip freeze
Django==2.0
pytz==2017.3
Simon Charette
Dec 4, 2017, 12:00:30 PM12/4/17
to Django users
Hello there,
This looks like a regression in Django 2.0 caused by 095c1aaa[0].
Please file a new ticket mentioning it's a regression in Django 2.0
and mark it as a release blocker. [1]
Thanks,
Simon
[0] https://github.com/django/django/commit/095c1aaa898bed40568009db836aa8434f1b983d
[1] https://code.djangoproject.com/newticket
This looks like a regression in Django 2.0 caused by 095c1aaa[0].
Please file a new ticket mentioning it's a regression in Django 2.0
and mark it as a release blocker. [1]
Thanks,
Simon
[0] https://github.com/django/django/commit/095c1aaa898bed40568009db836aa8434f1b983d
[1] https://code.djangoproject.com/newticket
edigi...@arpae.it
Dec 4, 2017, 1:11:49 PM12/4/17
to Django users
Reply all
Reply to author
Forward
0 new messages