0011_update_proxy_permissions crashes in multi database environment.

[haudoing]

The tutorial said that we can omit to set the default database if default doesn't makes sense
​https://docs.djangoproject.com/en/2.2/topics/db/multi-db/#defining-your-databases

But the following migration script doesn't work after configuration with empty default database
​https://github.com/django/django/blob/stable/2.2.x/django/contrib/auth/migrations/0011_update_proxy_permissions.py

on line 42, it use

            with transaction.atomic():
                Permission.objects.filter(
                    permissions_query,
                    content_type=old_content_type,
                ).update(content_type=new_content_type)

This will brake the migration if default database doesn't set

Tracebacks

    raise ImproperlyConfigured("settings.DATABASES is improperly configured. "
django.core.exceptions.ImproperlyConfigured: settings.DATABASES is improperly configured. Please supply the ENGINE value. Check settings documentation for more details.

[Mariusz Felisiak]

This migration doesn't brake anything for me. I checked with ​an example from docs and it doesn't require a default DB.

[haudoing]

Sorry for my poor English. I doesn't express it well. What I mean to say is not migration script brake the multi db setting. I want to say after configure multi database setting without default, the migration script won't work. It throw the following exception while migrate

    raise ImproperlyConfigured("settings.DATABASES is improperly configured. "
django.core.exceptions.ImproperlyConfigured: settings.DATABASES is improperly configured. Please supply the ENGINE value. Check settings documentation for more details.

[Mariusz Felisiak]

I want to say after configure multi database setting without default, the migration script won't work. It throw the following exception while migrate...

Just like I said, it works for me with ​an example from docs, that doesn't require a default DB. Please don't reopen this ticket without providing a small, sample project which we can use to reproduce this issue. You can also try to one of support channels.

[haudoing]

Hello Felixxm,

Thank you for your response. I found the actual reason cause this issue.
I do start a clean Django project with the example you provide, it really works fine.
But when I create a proxy model then migration stop at that script again.
The script of the proxy model I made is as following

```class EditorUser(User):

    class Meta:
        proxy = True

    def get_author_name(self):
        '''
        Returns:
            a name leading by last_name
        '''
        return '{}{}'.format(self.last_name, self.first_name)```

[Mariusz Felisiak]

I cannot reproduce this issue even with a proxy model :| . Can you attach a sample project?

[haudoing]

Thank you Felixxm.

I've attach a zip file with a very simple Django project. That should reproduce this issue.

[haudoing]

Sorry Felixxm,

The example is fine for brand new django 2.2.
It only appear when upgrade from 2.1 to 2.2

[Mariusz Felisiak]

I've tried to reproduce this issue with your project by following these steps:

• pip install Django~=2.1.0
• python manage.py migrate --database=auth_db
• python manage.py migrate --database=others
• pip install Django~=2.2.0
• python manage.py migrate --database=auth_db
• python manage.py migrate --database=others

and ... all works for me.

[haudoing]

Please add a steps while working on Django 2.1 before migrate.

python manage.py makemigrations

That should reproduce this exception.
Though I'm not sure is it qualified to be a bug now.
After all A.B version upgrade doesn't 100% guarantee backward compatible.
But if it doesn't, it should be included in the release note, which it doesn't.
​https://docs.djangoproject.com/en/2.2/releases/2.2/#permissions-for-proxy-models
Gotta thank you again felixxm!

[Mariusz Felisiak]

Many thanks! I was able to reproduce this issue, fix is quite simple:

diff --git a/django/contrib/auth/migrations/0011_update_proxy_permissions.py b/django/contrib/auth/migrations/0011_update_proxy_permissions.py
index c3f617f438..62e0a91737 100644
--- a/django/contrib/auth/migrations/0011_update_proxy_permissions.py
+++ b/django/contrib/auth/migrations/0011_update_proxy_permissions.py
@@ -39,7 +39,7 @@ def update_proxy_model_permissions(apps, schema_editor, reverse=False):
         old_content_type = proxy_content_type if reverse else concrete_content_type
         new_content_type = concrete_content_type if reverse else proxy_content_type
         try:
-            with transaction.atomic():
+            with transaction.atomic(using=schema_editor.connection.alias):
                 Permission.objects.filter(
                     permissions_query,
                     content_type=old_content_type,

[Mariusz Felisiak]

Regression in 98296f86b340c8c9c968375d59f1d3a3479e60c2.

[Mariusz Felisiak]

​PR

[Mariusz Felisiak <felisiak.mariusz@…>]

In e8fcdaad:

Fixed #31021 -- Fixed proxy model permissions data migration crash with a multiple databases setup.

Regression in 98296f86b340c8c9c968375d59f1d3a3479e60c2.

[Mariusz Felisiak <felisiak.mariusz@…>]

In ca9144a4:

[3.0.x] Fixed #31021 -- Fixed proxy model permissions data migration crash with a multiple databases setup.

Regression in 98296f86b340c8c9c968375d59f1d3a3479e60c2.

Backport of e8fcdaad5c428878d0a5d6ba820d957013f75595 from master

[Mariusz Felisiak <felisiak.mariusz@…>]

In 9a17ae50:

[2.2.x] Fixed #31021 -- Fixed proxy model permissions data migration crash with a multiple databases setup.

Regression in 98296f86b340c8c9c968375d59f1d3a3479e60c2.

Backport of e8fcdaad5c428878d0a5d6ba820d957013f75595 from master