migrate fails when installing zinnia for the first time on a production database

[skozan]

Actual behavior

Installing zinnia to a production system, fails on zinnia.0003_publication_date migration with some timeout.

It looks that fill_publication_date() function in "/zinnia/migrations/0003_publication_date.py" timeouts when trying to access entries with: for entry in entry_klass.objects.all(), but zinnia database is empty.

Exception follows:

(env) user@host:~/project_root$ ./manage.py migrate zinnia
Operations to perform:
  Apply all migrations: zinnia
Running migrations:
  Applying zinnia.0002_lead_paragraph_and_image_caption... OK
  Applying zinnia.0003_publication_date...Traceback (most recent call last):
  File "./manage.py", line 28, in <module>
    execute_from_command_line(sys.argv)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 364, in execute_from_command_line
    utility.execute()
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 356, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
 line 283, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/core/management/base.py", line 330, in execute
    output = self.handle(*args, **options)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 204, in handle
    fake_initial=fake_initial,
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/migrations/executor.py", line 115, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/migrations/executor.py", line 145, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/migrations/executor.py", line 244, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/migrations/migration.py", line 129, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/migrations/operations/special.py", line 193, in database_forwards
    self.code(from_state.apps, schema_editor)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/zinnia/migrations/0003_publication_date.py", line 7, in fill_publication_date
    for entry in entry_klass.objects.all():
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/models/query.py", line 250, in __iter__
    self._fetch_all()
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/models/query.py", line 1118, in _fetch_all
    self._result_cache = list(self._iterable_class(self))
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/models/query.py", line 53, in __iter__
    results = compiler.execute_sql(chunked_fetch=self.chunked_fetch)
  File "/home/user/project_root/env/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 899, in execute_sql
    raise original_exception
django.db.utils.OperationalError: canceling statement due to statement timeout

Expected behavior

Migrations, especially for a fresh zinnia installation without entries in database, should not raise time out exceptions, breaking also a deployment.

Workaround

Edited "0003_publication_date.py" file and added a return in fill_publication_date() so function body does not execute. Note that this may be ok only for a fresh - empty zinnia database.

Steps to reproduce the issue

1. Add zinnia to settings.INSTALLED_APPS
2. python manage.py migrate (or python manage.py migrate zinnia, same output).

Specifications

• Database: PostgreSQL 9.6.8
• Zinnia version: 0.19
• Django version: 1.11.9
• Python version: 2.7.12
• Operating system: Ubuntu 16.04

Disclaimer

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• Read the guidelines for contributing.
• Checked for duplicate issues.
• Not a support request.

[Fantomas42]

Hello,

I'm sorry but I cannot reproduce the issue.

On travis all I can see is that everything works on PG 9.6.6:
https://travis-ci.org/Fantomas42/django-blog-zinnia/jobs/351805880

The older builds have always worked.

Regards