Fixed #17653 -- Changed MySQL backend to raise a ValueError if zero is used as an AutoField value. (c4e62eff) · Commits · Dom Sekotill / django

django/db/backends/init.py

+8 −0

Original line number	Diff line number	Diff line
		@@ -770,6 +770,14 @@ class BaseDatabaseOperations(object):
		# need not necessarily be implemented using "LIKE" in the backend.
		prep_for_iexact_query = prep_for_like_query

		def validate_autopk_value(self, value):
		"""
		Certain backends do not accept some values for "serial" fields
		(for example zero in MySQL). This method will raise a ValueError
		if the value is invalid, otherwise returns validated value.
		"""
		return value

		def value_to_db_date(self, value):
		"""
		Transform a date value to an object compatible with what is expected

+7 −0

Original line number	Diff line number	Diff line
		@@ -276,6 +276,13 @@ class DatabaseOperations(BaseDatabaseOperations):
		else:
		return []

		def validate_autopk_value(self, value):
		# MySQLism: zero in AUTO_INCREMENT field does not work. Refs #17653.
		if value == 0:
		raise ValueError('The database backend does not accept 0 as a '
		'value for AutoField.')
		return value

		def value_to_db_datetime(self, value):
		if value is None:
		return None

+6 −0

Original line number	Diff line number	Diff line
		@@ -531,6 +531,12 @@ class AutoField(Field):
		def validate(self, value, model_instance):
		pass

		def get_db_prep_value(self, value, connection, prepared=False):
		if not prepared:
		value = self.get_prep_value(value)
		value = connection.ops.validate_autopk_value(value)
		return value

		def get_prep_value(self, value):
		if value is None:
		return None

+14 −1

Original line number	Diff line number	Diff line
		@@ -13,7 +13,8 @@ from django.db import (backend, connection, connections, DEFAULT_DB_ALIAS,
		from django.db.backends.signals import connection_created
		from django.db.backends.postgresql_psycopg2 import version as pg_version
		from django.db.utils import ConnectionHandler, DatabaseError, load_backend
		from django.test import TestCase, skipUnlessDBFeature, TransactionTestCase
		from django.test import (TestCase, skipUnlessDBFeature, skipIfDBFeature,
		TransactionTestCase)
		from django.test.utils import override_settings
		from django.utils import unittest

		@@ -642,3 +643,15 @@ class BackendLoadingTests(TestCase):
		self.assertRaisesRegexp(ImproperlyConfigured,
		"Try using django.db.backends.sqlite3 instead",
		load_backend, 'sqlite3')


		class MySQLPKZeroTests(TestCase):
		"""
		Zero as id for AutoField should raise exception in MySQL, because MySQL
		does not allow zero for automatic primary key.
		"""

		@skipIfDBFeature('allows_primary_key_0')
		def test_zero_as_autoval(self):
		with self.assertRaises(ValueError):
		models.Square.objects.create(id=0, root=0, square=1)

+14 −2

Original line number	Diff line number	Diff line
		@@ -2,7 +2,7 @@ from __future__ import absolute_import

		from operator import attrgetter

		from django.test import TestCase, skipUnlessDBFeature
		from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature

		from .models import Country, Restaurant, Pizzeria, State

		@@ -57,3 +57,15 @@ class BulkCreateTests(TestCase):
		self.assertQuerysetEqual(State.objects.order_by("two_letter_code"), [
		"CA", "IL", "ME", "NY",
		], attrgetter("two_letter_code"))

		@skipIfDBFeature('allows_primary_key_0')
		def test_zero_as_autoval(self):
		"""
		Zero as id for AutoField should raise exception in MySQL, because MySQL
		does not allow zero for automatic primary key.
		"""

		valid_country = Country(name='Germany', iso_two_letter='DE')
		invalid_country = Country(id=0, name='Poland', iso_two_letter='PL')
		with self.assertRaises(ValueError):
		Country.objects.bulk_create([valid_country, invalid_country])