Opened 10 years ago
Closed 10 years ago
#22713 closed Bug (duplicate)
Unable to load initial data with ForeignKey field during migration in 1.7b4
Reported by: | Owned by: | nobody | |
---|---|---|---|
Component: | Migrations | Version: | |
Severity: | Normal | Keywords: | |
Cc: | Triage Stage: | Unreviewed | |
Has patch: | no | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description
Here is a models.py from my really simple demoapp
from django.db import models class SimpleModel(models.Model): pass class ModelWithReference(models.Model): simplemodel = models.ForeignKey(SimpleModel, related_name='modelswithreference')
And migrations
in file 0001_initial.py # encoding: utf8 from __future__ import unicode_literals from django.db import models, migrations class Migration(migrations.Migration): dependencies = [ ] def load_initial_data(apps, schema_editor): simplemodel = apps.get_model('demoapp', 'SimpleModel') simplemodel.objects.create(id=1) simplemodel.objects.create(id=2) operations = [ migrations.CreateModel( name='SimpleModel', fields=[ ('id', models.AutoField(serialize=False, auto_created=True, verbose_name='ID', primary_key=True)), ], options={ }, bases=(models.Model,), ), migrations.RunPython(load_initial_data) ] and file 0002_modelwithreference.py # encoding: utf8 from __future__ import unicode_literals from django.db import models, migrations class Migration(migrations.Migration): dependencies = [ ('demoapp', '0001_initial'), ] def load_initial_data(apps, shema_editor): simplemodel = apps.get_model('demoapp', 'SimpleModel').objects.get(pk=1) modelwithreference = apps.get_model('demoapp', 'ModelWithReference') modelwithreference.objects.create(id=1, simplemodel=simplemodel) operations = [ migrations.CreateModel( name='ModelWithReference', fields=[ ('id', models.AutoField(serialize=False, primary_key=True, verbose_name='ID', auto_created=True)), ('simplemodel', models.ForeignKey(to='demoapp.SimpleModel', to_field='id')), ], options={ }, bases=(models.Model,), ), migrations.RunPython(load_initial_data) ]
Exception is
Running migrations: Applying demoapp.0001_initial... OK Applying demoapp.0002_modelwithreference...Traceback (most recent call last): File "./manage.py", line 10, in <module> execute_from_command_line(sys.argv) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/__init__.py", line 427, in execute_from_command_line utility.execute() File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/__init__.py", line 419, in execute self.fetch_command(subcommand).run_from_argv(self.argv) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/base.py", line 288, in run_from_argv self.execute(*args, **options.__dict__) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/base.py", line 337, in execute output = self.handle(*args, **options) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/commands/migrate.py", line 146, in handle executor.migrate(targets, plan, fake=options.get("fake", False)) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/executor.py", line 62, in migrate self.apply_migration(migration, fake=fake) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/executor.py", line 96, in apply_migration migration.apply(project_state, schema_editor) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/migration.py", line 107, in apply operation.database_forwards(self.app_label, schema_editor, project_state, new_state) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/operations/special.py", line 117, in database_forwards self.code(from_state.render(), schema_editor) File "/home/yuriy/dev/python/projects/demo/demoapp/migrations/0002_modelwithreference.py", line 16, in load_initial_data modelwithreference.objects.create(id=1, simplemodel=simplemodel) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/manager.py", line 92, in manager_method return getattr(self.get_queryset(), name)(*args, **kwargs) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/query.py", line 368, in create obj = self.model(**kwargs) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/base.py", line 444, in __init__ setattr(self, field.name, rel_obj) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/fields/related.py", line 597, in __set__ self.field.rel.to._meta.object_name, ValueError: Cannot assign "<SimpleModel: SimpleModel object>": "ModelWithReference.simplemodel" must be a "SimpleModel" instance.
Somehow it works if I get initial data loading from 0002_modelwithreference.py to another file, for example
file 0003_loadinitialdata.py # encoding: utf8 from __future__ import unicode_literals from django.db import models, migrations class Migration(migrations.Migration): dependencies = [ ('demoapp', '0002_modelwithreference'), ] def load_initial_data(apps, shema_editor): simplemodel = apps.get_model('demoapp', 'SimpleModel').objects.get(pk=1) modelwithreference= apps.get_model('demoapp', 'ModelWithReference') modelwithreference.objects.create(id=1, simplemodel=simplemodel) operations = [ migrations.RunPython(load_initial_data), ]
but it raises exception on first run and works on second. Result is:
(rest) yuriy@yuriy-$ rm db.sqlite3 (rest) yuriy@yuriy-$ ./manage.py migrate Operations to perform: Synchronize unmigrated apps: sessions, admin, auth, contenttypes Apply all migrations: demoapp Synchronizing apps without migrations: Creating tables... Creating table django_admin_log Creating table auth_permission Creating table auth_group_permissions Creating table auth_group Creating table auth_user_groups Creating table auth_user_user_permissions Creating table auth_user Creating table django_content_type Creating table django_session Installing custom SQL... Installing indexes... Running migrations: Applying demoapp.0001_initial... OK Applying demoapp.0002_modelwithreference... OK Applying demoapp.0003_loadinitialdata...Traceback (most recent call last): File "./manage.py", line 10, in <module> execute_from_command_line(sys.argv) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/__init__.py", line 427, in execute_from_command_line utility.execute() File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/__init__.py", line 419, in execute self.fetch_command(subcommand).run_from_argv(self.argv) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/base.py", line 288, in run_from_argv self.execute(*args, **options.__dict__) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/base.py", line 337, in execute output = self.handle(*args, **options) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/core/management/commands/migrate.py", line 146, in handle executor.migrate(targets, plan, fake=options.get("fake", False)) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/executor.py", line 62, in migrate self.apply_migration(migration, fake=fake) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/executor.py", line 96, in apply_migration migration.apply(project_state, schema_editor) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/migration.py", line 107, in apply operation.database_forwards(self.app_label, schema_editor, project_state, new_state) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/migrations/operations/special.py", line 117, in database_forwards self.code(from_state.render(), schema_editor) File "/home/yuriy/dev/python/projects/demo/demoapp/migrations/0003_loadinitialdata.py", line 17, in load_initial_data modelwithreference.objects.create(id=1, simplemodel=simplemodel) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/manager.py", line 92, in manager_method return getattr(self.get_queryset(), name)(*args, **kwargs) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/query.py", line 368, in create obj = self.model(**kwargs) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/base.py", line 444, in __init__ setattr(self, field.name, rel_obj) File "/home/yuriy/dev/python/environments/rest/lib/python3.4/site-packages/django/db/models/fields/related.py", line 597, in __set__ self.field.rel.to._meta.object_name, ValueError: Cannot assign "<SimpleModel: SimpleModel object>": "ModelWithReference.simplemodel" must be a "SimpleModel" instance. (rest) yuriy@yuriy-$ ./manage.py migrate Operations to perform: Synchronize unmigrated apps: contenttypes, sessions, admin, auth Apply all migrations: demoapp Synchronizing apps without migrations: Creating tables... Installing custom SQL... Installing indexes... Running migrations: Applying demoapp.0003_loadinitialdata... OK You have installed Django's auth system, and don't have any superusers defined. Would you like to create one now? (yes/no): no (rest) yuriy@yuriy-$
Note, that I removed database: rm db.sqlite3
first run ./manage.py migrate - exception, second run ./manage.py migrate - Applying demoapp.0003_loadinitialdata... OK
Attachments (1)
Change History (4)
by , 10 years ago
Attachment: | demoapp.tar.gz added |
---|
comment:1 by , 10 years ago
Could you try to see if the patch proposed in #22659 solves your issue.
I think both are related since CreateModel
operation are special cased and might reuse model state fields which could be the source of the ValueError
you're encountering.
comment:2 by , 10 years ago
Yes, it solves issues, with this patch migrations work as expected.
Thanks a lot for fast answer and solution.
comment:3 by , 10 years ago
Resolution: | → duplicate |
---|---|
Status: | new → closed |
Alright I'll mark this ticket as duplicate of #22659 in this case.
source code of demoapp application and migrations