the warning here to all safe_reraise() cases in Python 2.
- Revisiting :ticket:`2696`, first released in 1.0.10, which attempts to
work around Python 2's lack of exception context reporting by emitting
a warning for an exception that was interrupted by a second exception
when attempting to roll back the already-failed transaction; this
issue continues to occur for MySQL backends in conjunction with a
savepoint that gets unexpectedly lost, which then causes a
"no such savepoint" error when the rollback is attempted, obscuring
what the original condition was.
The approach has been generalized to the Core "safe
reraise" function which takes place across the ORM and Core in any
place that a transaction is being rolled back in response to an error
which occurred trying to commit, including the context managers
provided by :class:`.Session` and :class:`.Connection`, and taking
place for operations such as a failure on "RELEASE SAVEPOINT".
Previously, the fix was only in place for a specific path within
the ORM flush/commit process; it now takes place for all transational
context managers as well.
fixes #2696
:version: 1.0.12
:released:
+ .. change::
+ :tags: bug, engine, mysql
+ :tickets: 2696
+
+ Revisiting :ticket:`2696`, first released in 1.0.10, which attempts to
+ work around Python 2's lack of exception context reporting by emitting
+ a warning for an exception that was interrupted by a second exception
+ when attempting to roll back the already-failed transaction; this
+ issue continues to occur for MySQL backends in conjunction with a
+ savepoint that gets unexpectedly lost, which then causes a
+ "no such savepoint" error when the rollback is attempted, obscuring
+ what the original condition was.
+
+ The approach has been generalized to the Core "safe
+ reraise" function which takes place across the ORM and Core in any
+ place that a transaction is being rolled back in response to an error
+ which occurred trying to commit, including the context managers
+ provided by :class:`.Session` and :class:`.Connection`, and taking
+ place for operations such as a failure on "RELEASE SAVEPOINT".
+ Previously, the fix was only in place for a specific path within
+ the ORM flush/commit process; it now takes place for all transational
+ context managers as well.
+
.. change::
:tags: bug, sql
:tickets: 3632
for subtransaction in stx._iterate_parents(upto=self):
subtransaction.close()
- if _capture_exception:
- captured_exception = sys.exc_info()[1]
-
boundary = self
if self._state in (ACTIVE, PREPARED):
for transaction in self._iterate_parents():
if transaction._parent is None or transaction.nested:
- try:
- transaction._rollback_impl()
- except Exception:
- if _capture_exception:
- util.warn(
- "An exception raised during a Session "
- "persistence operation cannot be raised "
- "due to an additional ROLLBACK exception; "
- "the exception is: %s" % captured_exception)
- raise
+ transaction._rollback_impl()
transaction._state = DEACTIVE
boundary = transaction
break
self.close()
if self._parent and _capture_exception:
- self._parent._rollback_exception = captured_exception
+ self._parent._rollback_exception = sys.exc_info()[1]
sess.dispatch.after_soft_rollback(sess, self)
self._exc_info = None # remove potential circular references
compat.reraise(exc_type, exc_value, exc_tb)
else:
+ if not compat.py3k and self._exc_info and self._exc_info[1]:
+ # emulate Py3K's behavior of telling us when an exception
+ # occurs in an exception handler.
+ warn(
+ "An exception has occurred during handling of a "
+ "previous exception. The previous exception "
+ "is:\n %s %s\n" % (self._exc_info[0], self._exc_info[1]))
self._exc_info = None # remove potential circular references
compat.reraise(type_, value, traceback)
from sqlalchemy import util, sql, exc, testing
from sqlalchemy.testing import assert_raises, assert_raises_message, fixtures
-from sqlalchemy.testing import eq_, is_, ne_, fails_if, mock
+from sqlalchemy.testing import eq_, is_, ne_, fails_if, mock, expect_warnings
from sqlalchemy.testing.util import picklers, gc_collect
from sqlalchemy.util import classproperty, WeakSequence, get_callable_argspec
from sqlalchemy.sql import column
if testing.requires.python3.enabled:
is_(moe.__cause__, me)
+ @testing.requires.python2
+ def test_safe_reraise_py2k_warning(self):
+ class MyException(Exception):
+ pass
+
+ class MyOtherException(Exception):
+ pass
+
+ m1 = MyException("exc one")
+ m2 = MyOtherException("exc two")
+
+ def go2():
+ raise m2
+
+ def go():
+ try:
+ raise m1
+ except:
+ with util.safe_reraise():
+ go2()
+
+ with expect_warnings(
+ "An exception has occurred during handling of a previous "
+ "exception. The previous exception "
+ "is:.*MyException.*exc one"
+ ):
+ try:
+ go()
+ assert False
+ except MyOtherException:
+ pass
+
class TestClassProperty(fixtures.TestBase):
finally:
connection.close()
+ @testing.requires.python2
+ @testing.requires.savepoints_w_release
+ def test_savepoint_release_fails_warning(self):
+ with testing.db.connect() as connection:
+ connection.begin()
+
+ with expect_warnings(
+ "An exception has occurred during handling of a previous "
+ "exception. The previous exception "
+ "is:.*..SQL\:.*RELEASE SAVEPOINT"
+ ):
+ def go():
+ with connection.begin_nested() as savepoint:
+ connection.dialect.do_release_savepoint(
+ connection, savepoint._savepoint)
+ assert_raises_message(
+ exc.DBAPIError,
+ ".*SQL\:.*ROLLBACK TO SAVEPOINT",
+ go
+ )
+
def test_retains_through_options(self):
connection = testing.db.connect()
try:
assert session.transaction is not None, \
'autocommit=False should start a new transaction'
- @testing.skip_if("oracle", "oracle doesn't support release of savepoint")
- @testing.requires.savepoints
+ @testing.requires.python2
+ @testing.requires.savepoints_w_release
def test_report_primary_error_when_rollback_fails(self):
User, users = self.classes.User, self.tables.users
session = Session(testing.db)
- with expect_warnings(".*due to an additional ROLLBACK.*INSERT INTO"):
+ with expect_warnings(".*during handling of a previous exception.*"):
session.begin_nested()
savepoint = session.\
connection()._Connection__transaction._savepoint
("mysql", "<", (5, 0, 3)),
], "savepoints not supported")
+ @property
+ def savepoints_w_release(self):
+ return self.savepoints + skip_if(
+ "oracle", "oracle doesn't support release of savepoint")
@property
def schemas(self):