import unittest
from contextlib import contextmanager
from unittest import mock
from django.core.exceptions import ImproperlyConfigured
from django.db import NotSupportedError, connection
from django.test import TestCase, override_settings
@contextmanager
def get_connection():
new_connection = connection.copy()
yield new_connection
new_connection.close()
@override_settings(DEBUG=True)
@unittest.skipUnless(connection.vendor == "mysql", "MySQL tests")
class IsolationLevelTests(TestCase):
read_committed = "read committed"
repeatable_read = "repeatable read"
isolation_values = {level: level.upper() for level in (read_committed, repeatable_read)
}@classmethod
def setUpClass(cls):
super().setUpClass()
configured_isolation_level = (connection.isolation_level or cls.isolation_values[cls.repeatable_read]
)cls.configured_isolation_level = configured_isolation_level.upper()
cls.other_isolation_level = (
cls.read_committed
if configured_isolation_level != cls.isolation_values[cls.read_committed]
else cls.repeatable_read
)@staticmethod
def get_isolation_level(connection):
with connection.cursor() as cursor:
cursor.execute(
"SHOW VARIABLES "
"WHERE variable_name IN ('transaction_isolation', 'tx_isolation')"
)return cursor.fetchone()[1].replace("-", " ")
def test_auto_is_null_auto_config(self):
query = "set sql_auto_is_null = 0"
connection.init_connection_state()
last_query = connection.queries[-1]["sql"].lower()
if connection.features.is_sql_auto_is_null_enabled:
self.assertIn(query, last_query)
else:
self.assertNotIn(query, last_query)
def test_connect_isolation_level(self):
self.assertEqual(
self.get_isolation_level(connection), self.configured_isolation_level
)def test_setting_isolation_level(self):
with get_connection() as new_connection:
new_connection.settings_dict["OPTIONS"][
"isolation_level"
] = self.other_isolation_level
self.assertEqual(
self.get_isolation_level(new_connection),
self.isolation_values[self.other_isolation_level],
)def test_uppercase_isolation_level(self):
# Upper case values are also accepted in 'isolation_level'.
with get_connection() as new_connection:
new_connection.settings_dict["OPTIONS"][
"isolation_level"
] = self.other_isolation_level.upper()
self.assertEqual(
self.get_isolation_level(new_connection),
self.isolation_values[self.other_isolation_level],
)def test_default_isolation_level(self):
# If not specified in settings, the default is read committed.
with get_connection() as new_connection:
new_connection.settings_dict["OPTIONS"].pop("isolation_level", None)
self.assertEqual(
self.get_isolation_level(new_connection),
self.isolation_values[self.read_committed],
)def test_isolation_level_validation(self):
new_connection = connection.copy()
new_connection.settings_dict["OPTIONS"]["isolation_level"] = "xxx"
msg = ("Invalid transaction isolation level 'xxx' specified.\n"
"Use one of 'read committed', 'read uncommitted', "
"'repeatable read', 'serializable', or None."
)with self.assertRaisesMessage(ImproperlyConfigured, msg):
new_connection.cursor()
@unittest.skipUnless(connection.vendor == "mysql", "MySQL tests")
class Tests(TestCase):
@mock.patch.object(connection, "get_database_version")
def test_check_database_version_supported(self, mocked_get_database_version):
if connection.mysql_is_mariadb:
mocked_get_database_version.return_value = (10, 2)
msg = "MariaDB 10.3 or later is required (found 10.2)."
else:
mocked_get_database_version.return_value = (5, 6)
msg = "MySQL 5.7 or later is required (found 5.6)."
with self.assertRaisesMessage(NotSupportedError, msg):
connection.check_database_version_supported()
self.assertTrue(mocked_get_database_version.called)