Fixed #31246 -- Fixed locking models in QuerySet.select_for_update(of=()) for related fields and parent link fields with multi-table inheritance.

Partly regression in 0107e3d105.
This commit is contained in:
Abhijeet Viswa 2020-02-08 10:22:09 +05:30 committed by Mariusz Felisiak
parent 41a3b3d186
commit 1712a76b9d
6 changed files with 81 additions and 23 deletions

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@ -9,6 +9,7 @@ answer newbie questions, and generally made Django that much better:
Aaron Swartz <http://www.aaronsw.com/>
Aaron T. Myers <atmyers@gmail.com>
Abeer Upadhyay <ab.esquarer@gmail.com>
Abhijeet Viswa <abhijeetviswa@gmail.com>
Abhinav Patil <https://github.com/ubadub/>
Abhishek Gautam <abhishekg1128@yahoo.com>
Adam Allred <adam.w.allred@gmail.com>

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@ -961,19 +961,34 @@ class SQLCompiler:
the query.
"""
def _get_parent_klass_info(klass_info):
return (
{
for parent_model, parent_link in klass_info['model']._meta.parents.items():
parent_list = parent_model._meta.get_parent_list()
yield {
'model': parent_model,
'field': parent_link,
'reverse': False,
'select_fields': [
select_index
for select_index in klass_info['select_fields']
if self.select[select_index][0].target.model == parent_model
# Selected columns from a model or its parents.
if (
self.select[select_index][0].target.model == parent_model or
self.select[select_index][0].target.model in parent_list
)
],
}
for parent_model, parent_link in klass_info['model']._meta.parents.items()
)
def _get_first_selected_col_from_model(klass_info):
"""
Find the first selected column from a model. If it doesn't exist,
don't lock a model.
select_fields is filled recursively, so it also contains fields
from the parent models.
"""
for select_index in klass_info['select_fields']:
if self.select[select_index][0].target.model == klass_info['model']:
return self.select[select_index][0]
def _get_field_choices():
"""Yield all allowed field paths in breadth-first search order."""
@ -1002,14 +1017,7 @@ class SQLCompiler:
for name in self.query.select_for_update_of:
klass_info = self.klass_info
if name == 'self':
# Find the first selected column from a base model. If it
# doesn't exist, don't lock a base model.
for select_index in klass_info['select_fields']:
if self.select[select_index][0].target.model == klass_info['model']:
col = self.select[select_index][0]
break
else:
col = None
col = _get_first_selected_col_from_model(klass_info)
else:
for part in name.split(LOOKUP_SEP):
klass_infos = (
@ -1029,8 +1037,7 @@ class SQLCompiler:
if klass_info is None:
invalid_names.append(name)
continue
select_index = klass_info['select_fields'][0]
col = self.select[select_index][0]
col = _get_first_selected_col_from_model(klass_info)
if col is not None:
if self.connection.features.select_for_update_of_column:
result.append(self.compile(col)[0])

View File

@ -9,4 +9,8 @@ Django 2.2.11 fixes a data loss bug in 2.2.10.
Bugfixes
========
* ...
* Fixed a data loss possibility in the
:meth:`~django.db.models.query.QuerySet.select_for_update`. When using
related fields or parent link fields with :ref:`multi-table-inheritance` in
the ``of`` argument, the corresponding models were not locked
(:ticket:`31246`).

View File

@ -14,3 +14,9 @@ Bugfixes
* Fixed a regression in Django 3.0 that caused a file response using a
temporary file to be closed incorrectly (:ticket:`31240`).
* Fixed a data loss possibility in the
:meth:`~django.db.models.query.QuerySet.select_for_update`. When using
related fields or parent link fields with :ref:`multi-table-inheritance` in
the ``of`` argument, the corresponding models were not locked
(:ticket:`31246`).

View File

@ -1,7 +1,11 @@
from django.db import models
class Country(models.Model):
class Entity(models.Model):
pass
class Country(Entity):
name = models.CharField(max_length=30)

View File

@ -113,7 +113,10 @@ class SelectForUpdateTests(TransactionTestCase):
))
features = connections['default'].features
if features.select_for_update_of_column:
expected = ['select_for_update_person"."id', 'select_for_update_country"."id']
expected = [
'select_for_update_person"."id',
'select_for_update_country"."entity_ptr_id',
]
else:
expected = ['select_for_update_person', 'select_for_update_country']
expected = [connection.ops.quote_name(value) for value in expected]
@ -137,13 +140,29 @@ class SelectForUpdateTests(TransactionTestCase):
if connection.features.select_for_update_of_column:
expected = [
'select_for_update_eucountry"."country_ptr_id',
'select_for_update_country"."id',
'select_for_update_country"."entity_ptr_id',
]
else:
expected = ['select_for_update_eucountry', 'select_for_update_country']
expected = [connection.ops.quote_name(value) for value in expected]
self.assertTrue(self.has_for_update_sql(ctx.captured_queries, of=expected))
@skipUnlessDBFeature('has_select_for_update_of')
def test_for_update_sql_related_model_inheritance_generated_of(self):
with transaction.atomic(), CaptureQueriesContext(connection) as ctx:
list(EUCity.objects.select_related('country').select_for_update(
of=('self', 'country'),
))
if connection.features.select_for_update_of_column:
expected = [
'select_for_update_eucity"."id',
'select_for_update_eucountry"."country_ptr_id',
]
else:
expected = ['select_for_update_eucity', 'select_for_update_eucountry']
expected = [connection.ops.quote_name(value) for value in expected]
self.assertTrue(self.has_for_update_sql(ctx.captured_queries, of=expected))
@skipUnlessDBFeature('has_select_for_update_of')
def test_for_update_sql_model_inheritance_nested_ptr_generated_of(self):
with transaction.atomic(), CaptureQueriesContext(connection) as ctx:
@ -153,13 +172,29 @@ class SelectForUpdateTests(TransactionTestCase):
if connection.features.select_for_update_of_column:
expected = [
'select_for_update_eucity"."id',
'select_for_update_country"."id',
'select_for_update_country"."entity_ptr_id',
]
else:
expected = ['select_for_update_eucity', 'select_for_update_country']
expected = [connection.ops.quote_name(value) for value in expected]
self.assertTrue(self.has_for_update_sql(ctx.captured_queries, of=expected))
@skipUnlessDBFeature('has_select_for_update_of')
def test_for_update_sql_multilevel_model_inheritance_ptr_generated_of(self):
with transaction.atomic(), CaptureQueriesContext(connection) as ctx:
list(EUCountry.objects.select_for_update(
of=('country_ptr', 'country_ptr__entity_ptr'),
))
if connection.features.select_for_update_of_column:
expected = [
'select_for_update_country"."entity_ptr_id',
'select_for_update_entity"."id',
]
else:
expected = ['select_for_update_country', 'select_for_update_entity']
expected = [connection.ops.quote_name(value) for value in expected]
self.assertTrue(self.has_for_update_sql(ctx.captured_queries, of=expected))
@skipUnlessDBFeature('has_select_for_update_of')
def test_for_update_of_followed_by_values(self):
with transaction.atomic():
@ -264,7 +299,8 @@ class SelectForUpdateTests(TransactionTestCase):
msg = (
'Invalid field name(s) given in select_for_update(of=(...)): %s. '
'Only relational fields followed in the query are allowed. '
'Choices are: self, born, born__country.'
'Choices are: self, born, born__country, '
'born__country__entity_ptr.'
)
invalid_of = [
('nonexistent',),
@ -307,13 +343,13 @@ class SelectForUpdateTests(TransactionTestCase):
)
with self.assertRaisesMessage(
FieldError,
msg % 'country, country__country_ptr',
msg % 'country, country__country_ptr, country__country_ptr__entity_ptr',
):
with transaction.atomic():
EUCity.objects.select_related(
'country',
).select_for_update(of=('name',)).get()
with self.assertRaisesMessage(FieldError, msg % 'country_ptr'):
with self.assertRaisesMessage(FieldError, msg % 'country_ptr, country_ptr__entity_ptr'):
with transaction.atomic():
EUCountry.objects.select_for_update(of=('name',)).get()