[Django] #34849: Appending django.contrib.postgres to the INSTALLED_APPS via @modify

Django

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Sep 19, 2023, 3:00:11 AM9/19/23

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#34849: Appending django.contrib.postgres to the INSTALLED_APPS via
@modify_settings crashes.
-------------------------------------+-------------------------------------
Reporter: Mariusz | Owner: nobody
Felisiak |
Type: Bug | Status: new
Component: Database | Version: 5.0
layer (models, ORM) |
Severity: Release | Keywords:
blocker |
Triage Stage: | Has patch: 0
Unreviewed |
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-------------------------------------+-------------------------------------
Appending `django.contrib.postgres` to the `INSTALLED_APPS` via
`@modify_settings` crashes with:
{{{
RuntimeWarning: Accessing the database during app initialization is
discouraged. To fix this warning, avoid executing queries in
AppConfig.ready() or when your app modules are imported.
}}}
Check out:
{{{
./runtests.py postgres_tests
...
======================================================================
ERROR: test_register_serializer_for_migrations
(postgres_tests.test_apps.PostgresConfigTests)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/local/lib/python3.10/unittest/case.py", line 59, in
testPartExecutor
yield
File "/usr/local/lib/python3.10/unittest/case.py", line 591, in run
self._callTestMethod(testMethod)
File "/usr/local/lib/python3.10/unittest/case.py", line 549, in
_callTestMethod
method()
File "/django/tests/postgres_tests/test_apps.py", line 64, in
test_register_serializer_for_migrations
with self.modify_settings(INSTALLED_APPS={"append":
"django.contrib.postgres"}):
File "/django/django/test/utils.py", line 405, in __enter__
return self.enable()
File "/django/django/test/utils.py", line 587, in enable
super().enable()
File "/django/django/test/utils.py", line 474, in enable
apps.set_installed_apps(self.options["INSTALLED_APPS"])
File "/django/django/apps/registry.py", line 362, in set_installed_apps
self.populate(installed)
File "/django/django/apps/registry.py", line 124, in populate
app_config.ready()
File "/django/django/contrib/postgres/apps.py", line 71, in ready
register_type_handlers(conn)
File "/django/django/contrib/postgres/signals.py", line 40, in
register_type_handlers
oids, array_oids = get_hstore_oids(connection.alias)
File "/django/django/contrib/postgres/signals.py", line 24, in
get_hstore_oids
return get_type_oids(connection_alias, "hstore")
File "/django/django/contrib/postgres/signals.py", line 10, in
get_type_oids
cursor.execute(
File "/django/django/db/backends/utils.py", line 77, in execute
return self._execute_with_wrappers(
File "/django/django/db/backends/utils.py", line 90, in
_execute_with_wrappers
return executor(sql, params, many, context)
File "/django/django/db/backends/utils.py", line 94, in _execute
warnings.warn(self.APPS_NOT_READY_WARNING_MSG,
category=RuntimeWarning)
RuntimeWarning: Accessing the database during app initialization is
discouraged. To fix this warning, avoid executing queries in
AppConfig.ready() or when your app modules are imported.

======================================================================
ERROR: test_register_type_handlers_connection
(postgres_tests.test_apps.PostgresConfigTests)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/local/lib/python3.10/unittest/case.py", line 59, in
testPartExecutor
yield
File "/usr/local/lib/python3.10/unittest/case.py", line 591, in run
self._callTestMethod(testMethod)
File "/usr/local/lib/python3.10/unittest/case.py", line 549, in
_callTestMethod
method()
File "/django/tests/postgres_tests/test_apps.py", line 36, in
test_register_type_handlers_connection
with modify_settings(INSTALLED_APPS={"append":
"django.contrib.postgres"}):
File "/django/django/test/utils.py", line 405, in __enter__
return self.enable()
File "/django/django/test/utils.py", line 587, in enable
super().enable()
File "/django/django/test/utils.py", line 474, in enable
apps.set_installed_apps(self.options["INSTALLED_APPS"])
File "/django/django/apps/registry.py", line 362, in set_installed_apps
self.populate(installed)
File "/django/django/apps/registry.py", line 124, in populate
app_config.ready()
File "/django/django/contrib/postgres/apps.py", line 71, in ready
register_type_handlers(conn)
File "/django/django/contrib/postgres/signals.py", line 40, in
register_type_handlers
oids, array_oids = get_hstore_oids(connection.alias)
File "/django/django/contrib/postgres/signals.py", line 24, in
get_hstore_oids
return get_type_oids(connection_alias, "hstore")
File "/django/django/contrib/postgres/signals.py", line 10, in
get_type_oids
cursor.execute(
File "/django/django/db/backends/utils.py", line 77, in execute
return self._execute_with_wrappers(
File "/django/django/db/backends/utils.py", line 90, in
_execute_with_wrappers
return executor(sql, params, many, context)
File "/django/django/db/backends/utils.py", line 94, in _execute
warnings.warn(self.APPS_NOT_READY_WARNING_MSG,
category=RuntimeWarning)
RuntimeWarning: Accessing the database during app initialization is
discouraged. To fix this warning, avoid executing queries in
AppConfig.ready() or when your app modules are imported.

----------------------------------------------------------------------
Ran 590 tests in 1.840s

FAILED (errors=2, skipped=8, expected failures=3)
}}}

`@modify_settings` repopulates apps that register type handlers and hits
the database to select OIDs (if not cached).

Regression in fbd16438f46bc2128926958ad24331da5d1b406f (#33143).

--
Ticket URL: <https://code.djangoproject.com/ticket/34849>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.

Django

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Sep 19, 2023, 3:10:32 AM9/19/23

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#34849: Appending django.contrib.postgres to the INSTALLED_APPS via
@modify_settings crashes.
-------------------------------------+-------------------------------------

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by David Sanders):

* stage: Unreviewed => Accepted

--
Ticket URL: <https://code.djangoproject.com/ticket/34849#comment:1>

Django

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Sep 19, 2023, 4:12:01 PM9/19/23

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#34849: Appending django.contrib.postgres to the INSTALLED_APPS via
@modify_settings crashes.
-------------------------------------+-------------------------------------
Reporter: Mariusz Felisiak | Owner: nobody
Type: Bug | Status: new
Component: Database layer | Version: 5.0
(models, ORM) |
Severity: Release blocker | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Florian Zimmermann):

I'm super confused. Shouldn't Jenkins have picked this up earlier, i.e.
when fbd16438f46bc2128926958ad24331da5d1b406f (#33143) was merged?

--
Ticket URL: <https://code.djangoproject.com/ticket/34849#comment:2>

Django

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Sep 19, 2023, 4:48:23 PM9/19/23

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#34849: Appending django.contrib.postgres to the INSTALLED_APPS via
@modify_settings crashes.
-------------------------------------+-------------------------------------
Reporter: Mariusz Felisiak | Owner: nobody
Type: Bug | Status: new
Component: Database layer | Version: 5.0
(models, ORM) |
Severity: Release blocker | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Mariusz Felisiak):

> Shouldn't Jenkins have picked this up earlier, ...

No, it shouldn't. First of all we run the entire test suite not random
subsets of test classes. Secondly, this is quite tricky and you have to
debug how types are registered for `django.contrib.postgresql` and how
`@modify_settings` works:

- types are registered when connection is created by `connection_created`
handler, so it's not when app is initialized, so far so good,
- when `@modify_settings` manipulates `INSTALLED_APPS` then we undo
effects of `PostgresConfig.ready()`,
- `@modify_settings` calls `PostgresConfig.ready()` again, tries to
registered handlers for existing connections and hits the database to
select OIDs.

--
Ticket URL: <https://code.djangoproject.com/ticket/34849#comment:3>

Django

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Sep 19, 2023, 4:49:51 PM9/19/23

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#34849: Appending django.contrib.postgres to the INSTALLED_APPS via
@modify_settings crashes.
-------------------------------------+-------------------------------------
Reporter: Mariusz Felisiak | Owner: nobody
Type: Bug | Status: new
Component: Database layer | Version: 5.0
(models, ORM) |
Severity: Release blocker | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Florian Zimmermann):

Maybe worth noting: for me this depends on the `--parallel` option with
`--parallel 1` producing even more errors:

`--parallel 2` no errors:
{{{
> python runtests.py --settings test_postgres --parallel 2 postgres_tests
Found 590 test(s).
..........................................................................................................................x......x............x...............................................................................................................................................................................................................................................................................................................................................................................................................................................................
----------------------------------------------------------------------
Ran 590 tests in 7.974s

OK (expected failures=3)
}}}

`--parallel 4` two errors:
{{{
> python runtests.py --settings test_postgres --parallel 4 postgres_tests
Found 590 test(s).
EE........................................................................................................................x......x............x...............................................................................................................................................................................................................................................................................................................................................................................................................................................................

======================================================================
ERROR: test_register_serializer_for_migrations
(postgres_tests.test_apps.PostgresConfigTests)
----------------------------------------------------------------------
Traceback (most recent call last):

File "C:\Program Files\Python310\lib\unittest\case.py", line 59, in
testPartExecutor
yield
File "C:\Program Files\Python310\lib\unittest\case.py", line 591, in run
self._callTestMethod(testMethod)
File "C:\Program Files\Python310\lib\unittest\case.py", line 549, in
_callTestMethod
method()
File "D:\django\tests\postgres_tests\test_apps.py", line 64, in

test_register_serializer_for_migrations
with self.modify_settings(INSTALLED_APPS={"append":
"django.contrib.postgres"}):

File "D:\django\django\test\utils.py", line 405, in __enter__
return self.enable()
File "D:\django\django\test\utils.py", line 587, in enable
super().enable()
File "D:\django\django\test\utils.py", line 474, in enable
apps.set_installed_apps(self.options["INSTALLED_APPS"])
File "D:\django\django\apps\registry.py", line 362, in
set_installed_apps
self.populate(installed)
File "D:\django\django\apps\registry.py", line 124, in populate
app_config.ready()
File "D:\django\django\contrib\postgres\apps.py", line 71, in ready
register_type_handlers(conn)
File "D:\django\django\contrib\postgres\signals.py", line 40, in

register_type_handlers
oids, array_oids = get_hstore_oids(connection.alias)

File "D:\django\django\contrib\postgres\signals.py", line 24, in

get_hstore_oids
return get_type_oids(connection_alias, "hstore")

File "D:\django\django\contrib\postgres\signals.py", line 10, in
get_type_oids
cursor.execute(
File "D:\django\django\db\backends\utils.py", line 77, in execute
return self._execute_with_wrappers(
File "D:\django\django\db\backends\utils.py", line 90, in

_execute_with_wrappers
return executor(sql, params, many, context)

File "D:\django\django\db\backends\utils.py", line 94, in _execute

warnings.warn(self.APPS_NOT_READY_WARNING_MSG,
category=RuntimeWarning)
RuntimeWarning: Accessing the database during app initialization is
discouraged. To fix this warning, avoid executing queries in
AppConfig.ready() or when your app modules are imported.

======================================================================
ERROR: test_register_type_handlers_connection
(postgres_tests.test_apps.PostgresConfigTests)
----------------------------------------------------------------------
Traceback (most recent call last):

File "C:\Program Files\Python310\lib\unittest\case.py", line 59, in
testPartExecutor
yield
File "C:\Program Files\Python310\lib\unittest\case.py", line 591, in run
self._callTestMethod(testMethod)
File "C:\Program Files\Python310\lib\unittest\case.py", line 549, in
_callTestMethod
method()
File "D:\django\tests\postgres_tests\test_apps.py", line 36, in

test_register_type_handlers_connection
with modify_settings(INSTALLED_APPS={"append":
"django.contrib.postgres"}):