def test_force_update(self):
c = Counter.objects.create(name="one", value=1)
# The normal case
c.value = 2
c.save()
# Same thing, via an update
c.value = 3
c.save(force_update=True)
# Won't work because force_update and force_insert are mutually
# exclusive
c.value = 4
self.assertRaises(ValueError, c.save, force_insert=True, force_update=True)
# Try to update something that doesn't have a primary key in the first
# place.
c1 = Counter(name="two", value=2)
self.assertRaises(ValueError, c1.save, force_update=True)
c1.save(force_insert=True)
# Won't work because we can't insert a pk of the same value.
sid = transaction.savepoint()
c.value = 5
self.assertRaises(IntegrityError, c.save, force_insert=True)
transaction.savepoint_rollback(sid)
# Trying to update should still fail, even with manual primary keys, if
# the data isn't in the database already.
obj = WithCustomPK(name=1, value=1)
self.assertRaises(DatabaseError, obj.save, force_update=True)
def test_required_pk(self):
# The primary key must be specified, so an error is raised if you
# try to create an object without it.
sid = transaction.savepoint()
self.assertRaises(IntegrityError,
Employee.objects.create, first_name="Tom", last_name="Smith"
)
transaction.savepoint_rollback(sid)
def work():
mod = Mod.objects.create(fld=1)
pk = mod.pk
sid = transaction.savepoint()
mod1 = Mod.objects.filter(pk=pk).update(fld=20)
transaction.savepoint_rollback(sid)
mod2 = Mod.objects.get(pk=pk)
transaction.commit()
self.assertEqual(mod2.fld, 1)
def test_unique_pk(self):
# The primary key must also obviously be unique, so trying to create a
# new object with the same primary key will fail.
e = Employee.objects.create(
employee_code=123, first_name="Frank", last_name="Jones"
)
sid = transaction.savepoint()
self.assertRaises(IntegrityError,
Employee.objects.create, employee_code=123, first_name="Fred", last_name="Jones"
)
transaction.savepoint_rollback(sid)
def test_multiple_o2o(self):
# One-to-one fields still work if you create your own primary key
o1 = ManualPrimaryKey(primary_key="abc123", name="primary")
o1.save()
o2 = RelatedModel(link=o1, name="secondary")
o2.save()
# You can have multiple one-to-one fields on a model, too.
x1 = MultiModel(link1=self.p1, link2=o1, name="x1")
x1.save()
self.assertEqual(repr(o1.multimodel), '<MultiModel: Multimodel x1>')
# This will fail because each one-to-one field must be unique (and
# link2=o1 was used for x1, above).
sid = transaction.savepoint()
mm = MultiModel(link1=self.p2, link2=o1, name="x1")
self.assertRaises(IntegrityError, mm.save)
transaction.savepoint_rollback(sid)
def save(self, must_create=False):
"""
Saves the current session data to the database. If 'must_create' is
True, a database error will be raised if the saving operation doesn't
create a *new* entry (as opposed to possibly updating an existing
entry).
"""
obj = Session(
session_key=self._get_or_create_session_key(),
session_data=self.encode(self._get_session(no_load=must_create)),
expire_date=self.get_expiry_date(),
)
using = router.db_for_write(Session, instance=obj)
sid = transaction.savepoint(using=using)
try:
obj.save(force_insert=must_create, using=using)
except IntegrityError:
if must_create:
transaction.savepoint_rollback(sid, using=using)
raise CreateError
raise