From a6fe4dc0c8ebc346a90dd849a86dac9345d74515 Mon Sep 17 00:00:00 2001 From: Mike Bayer Date: Thu, 19 Nov 2015 15:45:17 -0500 Subject: [PATCH] - A rare case which occurs when a :meth:`.Session.rollback` fails in the scope of a :meth:`.Session.flush` operation that's raising an exception, as has been observed in some MySQL SAVEPOINT cases, prevents the original database exception from being observed when it was emitted during flush, but only on Py2K because Py2K does not support exception chaining; on Py3K the originating exception is chained. As a workaround, a warning is emitted in this specific case showing at least the string message of the original database error before we proceed to raise the rollback-originating exception. fixes #2696 --- doc/build/changelog/changelog_10.rst | 15 +++++++++++++++ lib/sqlalchemy/orm/session.py | 16 ++++++++++++++-- lib/sqlalchemy/testing/assertions.py | 2 +- test/orm/test_transaction.py | 25 +++++++++++++++++++++++++ 4 files changed, 55 insertions(+), 3 deletions(-) diff --git a/doc/build/changelog/changelog_10.rst b/doc/build/changelog/changelog_10.rst index c800647a69..40a251a222 100644 --- a/doc/build/changelog/changelog_10.rst +++ b/doc/build/changelog/changelog_10.rst @@ -18,6 +18,21 @@ .. changelog:: :version: 1.0.10 + .. change:: + :tags: bug, orm + :versions: 1.1.0b1 + :tickets: 2696 + + A rare case which occurs when a :meth:`.Session.rollback` fails in the + scope of a :meth:`.Session.flush` operation that's raising an + exception, as has been observed in some MySQL SAVEPOINT cases, prevents + the original database exception from being observed when it was + emitted during flush, but only on Py2K because Py2K does not support + exception chaining; on Py3K the originating exception is chained. As + a workaround, a warning is emitted in this specific case showing at + least the string message of the original database error before we + proceed to raise the rollback-originating exception. + .. change:: :tags: bug, postgresql :versions: 1.1.0b1 diff --git a/lib/sqlalchemy/orm/session.py b/lib/sqlalchemy/orm/session.py index c726443f65..4272d7d785 100644 --- a/lib/sqlalchemy/orm/session.py +++ b/lib/sqlalchemy/orm/session.py @@ -408,11 +408,23 @@ class SessionTransaction(object): 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: - transaction._rollback_impl() + 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._state = DEACTIVE boundary = transaction break @@ -434,7 +446,7 @@ class SessionTransaction(object): self.close() if self._parent and _capture_exception: - self._parent._rollback_exception = sys.exc_info()[1] + self._parent._rollback_exception = captured_exception sess.dispatch.after_soft_rollback(sess, self) diff --git a/lib/sqlalchemy/testing/assertions.py b/lib/sqlalchemy/testing/assertions.py index 21dc3e71ac..63667654d4 100644 --- a/lib/sqlalchemy/testing/assertions.py +++ b/lib/sqlalchemy/testing/assertions.py @@ -121,7 +121,7 @@ def uses_deprecated(*messages): def _expect_warnings(exc_cls, messages, regex=True, assert_=True): if regex: - filters = [re.compile(msg, re.I) for msg in messages] + filters = [re.compile(msg, re.I | re.S) for msg in messages] else: filters = messages diff --git a/test/orm/test_transaction.py b/test/orm/test_transaction.py index 73c6b977ac..3ec6b9c093 100644 --- a/test/orm/test_transaction.py +++ b/test/orm/test_transaction.py @@ -657,6 +657,31 @@ class SessionTransactionTest(FixtureTest): assert session.transaction is not None, \ 'autocommit=False should start a new transaction' + @testing.requires.savepoints + def test_report_primary_error_when_rollback_fails(self): + User, users = self.classes.User, self.tables.users + + mapper(User, users) + + session = Session(testing.db) + + with expect_warnings(".*due to an additional ROLLBACK.*INSERT INTO"): + session.begin_nested() + savepoint = session.\ + connection()._Connection__transaction._savepoint + + # force the savepoint to disappear + session.execute("RELEASE SAVEPOINT %s" % savepoint) + + # now do a broken flush + session.add_all([User(id=1), User(id=1)]) + + assert_raises_message( + sa_exc.DBAPIError, + "ROLLBACK TO SAVEPOINT ", + session.flush + ) + class _LocalFixture(FixtureTest): run_setup_mappers = 'once' -- 2.47.2