Files
sqlalchemy/test/engine/test_reconnect.py
T
Mike Bayer 1b6c149770 Ensure all nested exception throws have a cause
Applied an explicit "cause" to most if not all internally raised exceptions
that are raised from within an internal exception catch, to avoid
misleading stacktraces that suggest an error within the handling of an
exception.  While it would be preferable to suppress the internally caught
exception in the way that the ``__suppress_context__`` attribute would,
there does not as yet seem to be a way to do this without suppressing an
enclosing user constructed context, so for now it exposes the internally
caught exception as the cause so that full information about the context
of the error is maintained.

Fixes: #4849
Change-Id: I55a86b29023675d9e5e49bc7edc5a2dc0bcd4751
(cherry picked from commit 8be0dae77a7e0747f0d0fb4282db4aea7f41e03a)
2020-03-02 18:49:12 -05:00

1116 lines
32 KiB
Python

import time
import sqlalchemy as tsa
from sqlalchemy import create_engine
from sqlalchemy import event
from sqlalchemy import exc
from sqlalchemy import Integer
from sqlalchemy import MetaData
from sqlalchemy import pool
from sqlalchemy import select
from sqlalchemy import String
from sqlalchemy import testing
from sqlalchemy import util
from sqlalchemy.engine import url
from sqlalchemy.testing import assert_raises
from sqlalchemy.testing import assert_raises_message
from sqlalchemy.testing import assert_raises_message_context_ok
from sqlalchemy.testing import engines
from sqlalchemy.testing import eq_
from sqlalchemy.testing import expect_warnings
from sqlalchemy.testing import fixtures
from sqlalchemy.testing import is_false
from sqlalchemy.testing import is_true
from sqlalchemy.testing import mock
from sqlalchemy.testing import ne_
from sqlalchemy.testing.engines import testing_engine
from sqlalchemy.testing.mock import call
from sqlalchemy.testing.mock import Mock
from sqlalchemy.testing.mock import patch
from sqlalchemy.testing.schema import Column
from sqlalchemy.testing.schema import Table
from sqlalchemy.testing.util import gc_collect
class MockError(Exception):
pass
class MockDisconnect(MockError):
pass
class MockExitIsh(BaseException):
pass
def mock_connection():
def mock_cursor():
def execute(*args, **kwargs):
if conn.explode == "execute":
raise MockDisconnect("Lost the DB connection on execute")
elif conn.explode == "interrupt":
conn.explode = "explode_no_disconnect"
raise MockExitIsh("Keyboard / greenlet / etc interruption")
elif conn.explode == "interrupt_dont_break":
conn.explode = None
raise MockExitIsh("Keyboard / greenlet / etc interruption")
elif conn.explode in (
"execute_no_disconnect",
"explode_no_disconnect",
):
raise MockError(
"something broke on execute but we didn't lose the "
"connection"
)
elif conn.explode in (
"rollback",
"rollback_no_disconnect",
"explode_no_disconnect",
):
raise MockError(
"something broke on execute but we didn't lose the "
"connection"
)
elif args and "SELECT" in args[0]:
cursor.description = [("foo", None, None, None, None, None)]
else:
return
def close():
cursor.fetchall = cursor.fetchone = Mock(
side_effect=MockError("cursor closed")
)
cursor = Mock(
execute=Mock(side_effect=execute), close=Mock(side_effect=close)
)
return cursor
def cursor():
while True:
yield mock_cursor()
def rollback():
if conn.explode == "rollback":
raise MockDisconnect("Lost the DB connection on rollback")
if conn.explode == "rollback_no_disconnect":
raise MockError(
"something broke on rollback but we didn't lose the "
"connection"
)
else:
return
conn = Mock(
rollback=Mock(side_effect=rollback), cursor=Mock(side_effect=cursor())
)
return conn
def MockDBAPI():
connections = []
stopped = [False]
def connect():
while True:
if stopped[0]:
raise MockDisconnect("database is stopped")
conn = mock_connection()
connections.append(conn)
yield conn
def shutdown(explode="execute", stop=False):
stopped[0] = stop
for c in connections:
c.explode = explode
def restart():
stopped[0] = False
connections[:] = []
def dispose():
stopped[0] = False
for c in connections:
c.explode = None
connections[:] = []
return Mock(
connect=Mock(side_effect=connect()),
shutdown=Mock(side_effect=shutdown),
dispose=Mock(side_effect=dispose),
restart=Mock(side_effect=restart),
paramstyle="named",
connections=connections,
Error=MockError,
)
class PrePingMockTest(fixtures.TestBase):
def setup(self):
self.dbapi = MockDBAPI()
def _pool_fixture(self, pre_ping):
dialect = url.make_url(
"postgresql://foo:bar@localhost/test"
).get_dialect()()
dialect.dbapi = self.dbapi
_pool = pool.QueuePool(
creator=lambda: self.dbapi.connect("foo.db"),
pre_ping=pre_ping,
dialect=dialect,
)
dialect.is_disconnect = lambda e, conn, cursor: isinstance(
e, MockDisconnect
)
return _pool
def teardown(self):
self.dbapi.dispose()
def test_connect_across_restart(self):
pool = self._pool_fixture(pre_ping=True)
conn = pool.connect()
stale_connection = conn.connection
conn.close()
self.dbapi.shutdown("execute")
self.dbapi.restart()
conn = pool.connect()
cursor = conn.cursor()
cursor.execute("hi")
stale_cursor = stale_connection.cursor()
assert_raises(MockDisconnect, stale_cursor.execute, "hi")
def test_raise_db_is_stopped(self):
pool = self._pool_fixture(pre_ping=True)
conn = pool.connect()
conn.close()
self.dbapi.shutdown("execute", stop=True)
assert_raises_message_context_ok(
MockDisconnect, "database is stopped", pool.connect
)
def test_waits_til_exec_wo_ping_db_is_stopped(self):
pool = self._pool_fixture(pre_ping=False)
conn = pool.connect()
conn.close()
self.dbapi.shutdown("execute", stop=True)
conn = pool.connect()
cursor = conn.cursor()
assert_raises_message(
MockDisconnect,
"Lost the DB connection on execute",
cursor.execute,
"foo",
)
def test_waits_til_exec_wo_ping_db_is_restarted(self):
pool = self._pool_fixture(pre_ping=False)
conn = pool.connect()
conn.close()
self.dbapi.shutdown("execute", stop=True)
self.dbapi.restart()
conn = pool.connect()
cursor = conn.cursor()
assert_raises_message(
MockDisconnect,
"Lost the DB connection on execute",
cursor.execute,
"foo",
)
@testing.requires.predictable_gc
def test_pre_ping_weakref_finalizer(self):
pool = self._pool_fixture(pre_ping=True)
conn = pool.connect()
old_dbapi_conn = conn.connection
conn.close()
eq_(old_dbapi_conn.mock_calls, [call.cursor(), call.rollback()])
self.dbapi.shutdown("execute", stop=True)
self.dbapi.restart()
conn = pool.connect()
dbapi_conn = conn.connection
del conn
gc_collect()
# new connection was reset on return appropriately
eq_(dbapi_conn.mock_calls, [call.cursor(), call.rollback()])
# old connection was just closed - did not get an
# erroneous reset on return
eq_(
old_dbapi_conn.mock_calls,
[call.cursor(), call.rollback(), call.cursor(), call.close()],
)
class MockReconnectTest(fixtures.TestBase):
def setup(self):
self.dbapi = MockDBAPI()
self.db = testing_engine(
"postgresql://foo:bar@localhost/test",
options=dict(module=self.dbapi, _initialize=False),
)
self.mock_connect = call(
host="localhost", password="bar", user="foo", database="test"
)
# monkeypatch disconnect checker
self.db.dialect.is_disconnect = lambda e, conn, cursor: isinstance(
e, MockDisconnect
)
def teardown(self):
self.dbapi.dispose()
def test_reconnect(self):
"""test that an 'is_disconnect' condition will invalidate the
connection, and additionally dispose the previous connection
pool and recreate."""
# make a connection
conn = self.db.connect()
# connection works
conn.execute(select([1]))
# create a second connection within the pool, which we'll ensure
# also goes away
conn2 = self.db.connect()
conn2.close()
# two connections opened total now
assert len(self.dbapi.connections) == 2
# set it to fail
self.dbapi.shutdown()
assert_raises(tsa.exc.DBAPIError, conn.execute, select([1]))
# assert was invalidated
assert not conn.closed
assert conn.invalidated
# close shouldn't break
conn.close()
# ensure one connection closed...
eq_(
[c.close.mock_calls for c in self.dbapi.connections],
[[call()], []],
)
conn = self.db.connect()
eq_(
[c.close.mock_calls for c in self.dbapi.connections],
[[call()], [call()], []],
)
conn.execute(select([1]))
conn.close()
eq_(
[c.close.mock_calls for c in self.dbapi.connections],
[[call()], [call()], []],
)
def test_invalidate_trans(self):
conn = self.db.connect()
trans = conn.begin()
self.dbapi.shutdown()
assert_raises(tsa.exc.DBAPIError, conn.execute, select([1]))
eq_([c.close.mock_calls for c in self.dbapi.connections], [[call()]])
assert not conn.closed
assert conn.invalidated
assert trans.is_active
assert_raises_message(
tsa.exc.StatementError,
"Can't reconnect until invalid transaction is rolled back",
conn.execute,
select([1]),
)
assert trans.is_active
assert_raises_message(
tsa.exc.InvalidRequestError,
"Can't reconnect until invalid transaction is rolled back",
trans.commit,
)
assert trans.is_active
trans.rollback()
assert not trans.is_active
conn.execute(select([1]))
assert not conn.invalidated
eq_(
[c.close.mock_calls for c in self.dbapi.connections],
[[call()], []],
)
def test_invalidate_dont_call_finalizer(self):
conn = self.db.connect()
finalizer = mock.Mock()
conn.connection._connection_record.finalize_callback.append(finalizer)
conn.invalidate()
assert conn.invalidated
eq_(finalizer.call_count, 0)
def test_conn_reusable(self):
conn = self.db.connect()
conn.execute(select([1]))
eq_(self.dbapi.connect.mock_calls, [self.mock_connect])
self.dbapi.shutdown()
assert_raises(tsa.exc.DBAPIError, conn.execute, select([1]))
assert not conn.closed
assert conn.invalidated
eq_([c.close.mock_calls for c in self.dbapi.connections], [[call()]])
# test reconnects
conn.execute(select([1]))
assert not conn.invalidated
eq_(
[c.close.mock_calls for c in self.dbapi.connections],
[[call()], []],
)
def test_invalidated_close(self):
conn = self.db.connect()
self.dbapi.shutdown()
assert_raises(tsa.exc.DBAPIError, conn.execute, select([1]))
conn.close()
assert conn.closed
assert conn.invalidated
assert_raises_message(
tsa.exc.StatementError,
"This Connection is closed",
conn.execute,
select([1]),
)
def test_noreconnect_execute_plus_closewresult(self):
conn = self.db.connect(close_with_result=True)
self.dbapi.shutdown("execute_no_disconnect")
# raises error
assert_raises_message(
tsa.exc.DBAPIError,
"something broke on execute but we didn't lose the connection",
conn.execute,
select([1]),
)
assert conn.closed
assert not conn.invalidated
def test_noreconnect_rollback_plus_closewresult(self):
conn = self.db.connect(close_with_result=True)
self.dbapi.shutdown("rollback_no_disconnect")
# raises error
with expect_warnings(
"An exception has occurred during handling .*"
"something broke on execute but we didn't lose the connection",
py2konly=True,
):
assert_raises_message(
tsa.exc.DBAPIError,
"something broke on rollback but we didn't "
"lose the connection",
conn.execute,
select([1]),
)
assert conn.closed
assert not conn.invalidated
assert_raises_message(
tsa.exc.StatementError,
"This Connection is closed",
conn.execute,
select([1]),
)
def test_reconnect_on_reentrant(self):
conn = self.db.connect()
conn.execute(select([1]))
assert len(self.dbapi.connections) == 1
self.dbapi.shutdown("rollback")
# raises error
with expect_warnings(
"An exception has occurred during handling .*"
"something broke on execute but we didn't lose the connection",
py2konly=True,
):
assert_raises_message(
tsa.exc.DBAPIError,
"Lost the DB connection on rollback",
conn.execute,
select([1]),
)
assert not conn.closed
assert conn.invalidated
def test_reconnect_on_reentrant_plus_closewresult(self):
conn = self.db.connect(close_with_result=True)
self.dbapi.shutdown("rollback")
# raises error
with expect_warnings(
"An exception has occurred during handling .*"
"something broke on execute but we didn't lose the connection",
py2konly=True,
):
assert_raises_message(
tsa.exc.DBAPIError,
"Lost the DB connection on rollback",
conn.execute,
select([1]),
)
assert conn.closed
assert conn.invalidated
assert_raises_message(
tsa.exc.StatementError,
"This Connection is closed",
conn.execute,
select([1]),
)
def test_check_disconnect_no_cursor(self):
conn = self.db.connect()
result = conn.execute(select([1]))
result.cursor.close()
conn.close()
assert_raises_message(
tsa.exc.DBAPIError, "cursor closed", list, result
)
def test_dialect_initialize_once(self):
from sqlalchemy.engine.url import URL
from sqlalchemy.engine.default import DefaultDialect
dbapi = self.dbapi
class MyURL(URL):
def _get_entrypoint(self):
return Dialect
def get_dialect(self):
return Dialect
class Dialect(DefaultDialect):
initialize = Mock()
engine = create_engine(MyURL("foo://"), module=dbapi)
engine.connect()
# note that the dispose() call replaces the old pool with a new one;
# this is to test that even though a single pool is using
# dispatch.exec_once(), by replacing the pool with a new one, the event
# would normally fire again onless once=True is set on the original
# listen as well.
engine.dispose()
engine.connect()
eq_(Dialect.initialize.call_count, 1)
def test_dialect_initialize_retry_if_exception(self):
from sqlalchemy.engine.url import URL
from sqlalchemy.engine.default import DefaultDialect
dbapi = self.dbapi
class MyURL(URL):
def _get_entrypoint(self):
return Dialect
def get_dialect(self):
return Dialect
class Dialect(DefaultDialect):
initialize = Mock()
# note that the first_connect hook is only invoked when the pool
# makes a new DBAPI connection, and not when it checks out an existing
# connection. So there is a dependency here that if the initializer
# raises an exception, the pool-level connection attempt is also
# failed, meaning no DBAPI connection is pooled. If the first_connect
# exception raise did not prevent the connection from being pooled,
# there could be the case where the pool could return that connection
# on a subsequent attempt without initialization having proceeded.
Dialect.initialize.side_effect = TypeError
engine = create_engine(MyURL("foo://"), module=dbapi)
assert_raises(TypeError, engine.connect)
eq_(Dialect.initialize.call_count, 1)
is_true(engine.pool._pool.empty())
assert_raises(TypeError, engine.connect)
eq_(Dialect.initialize.call_count, 2)
is_true(engine.pool._pool.empty())
engine.dispose()
assert_raises(TypeError, engine.connect)
eq_(Dialect.initialize.call_count, 3)
is_true(engine.pool._pool.empty())
Dialect.initialize.side_effect = None
conn = engine.connect()
eq_(Dialect.initialize.call_count, 4)
conn.close()
is_false(engine.pool._pool.empty())
conn = engine.connect()
eq_(Dialect.initialize.call_count, 4)
conn.close()
is_false(engine.pool._pool.empty())
engine.dispose()
conn = engine.connect()
eq_(Dialect.initialize.call_count, 4)
conn.close()
is_false(engine.pool._pool.empty())
def test_invalidate_conn_w_contextmanager_interrupt(self):
# test [ticket:3803]
pool = self.db.pool
conn = self.db.connect()
self.dbapi.shutdown("interrupt")
def go():
with conn.begin():
conn.execute(select([1]))
assert_raises(MockExitIsh, go)
assert conn.invalidated
eq_(pool._invalidate_time, 0) # pool not invalidated
conn.execute(select([1]))
assert not conn.invalidated
def test_invalidate_conn_interrupt_nodisconnect_workaround(self):
# test [ticket:3803] workaround for no disconnect on keyboard interrupt
@event.listens_for(self.db, "handle_error")
def cancel_disconnect(ctx):
ctx.is_disconnect = False
pool = self.db.pool
conn = self.db.connect()
self.dbapi.shutdown("interrupt_dont_break")
def go():
with conn.begin():
conn.execute(select([1]))
assert_raises(MockExitIsh, go)
assert not conn.invalidated
eq_(pool._invalidate_time, 0) # pool not invalidated
conn.execute(select([1]))
assert not conn.invalidated
def test_invalidate_conn_w_contextmanager_disconnect(self):
# test [ticket:3803] change maintains old behavior
pool = self.db.pool
conn = self.db.connect()
self.dbapi.shutdown("execute")
def go():
with conn.begin():
conn.execute(select([1]))
assert_raises(exc.DBAPIError, go) # wraps a MockDisconnect
assert conn.invalidated
ne_(pool._invalidate_time, 0) # pool is invalidated
conn.execute(select([1]))
assert not conn.invalidated
class CursorErrTest(fixtures.TestBase):
# this isn't really a "reconnect" test, it's more of
# a generic "recovery". maybe this test suite should have been
# named "test_error_recovery".
def _fixture(self, explode_on_exec, initialize):
class DBAPIError(Exception):
pass
def MockDBAPI():
def cursor():
while True:
if explode_on_exec:
yield Mock(
description=[],
close=Mock(side_effect=DBAPIError("explode")),
execute=Mock(side_effect=DBAPIError("explode")),
)
else:
yield Mock(
description=[],
close=Mock(side_effect=Exception("explode")),
)
def connect():
while True:
yield Mock(
spec=["cursor", "commit", "rollback", "close"],
cursor=Mock(side_effect=cursor()),
)
return Mock(
Error=DBAPIError,
paramstyle="qmark",
connect=Mock(side_effect=connect()),
)
dbapi = MockDBAPI()
from sqlalchemy.engine import default
url = Mock(
get_dialect=lambda: default.DefaultDialect,
_get_entrypoint=lambda: default.DefaultDialect,
_instantiate_plugins=lambda kwargs: (),
translate_connect_args=lambda: {},
query={},
)
eng = testing_engine(
url, options=dict(module=dbapi, _initialize=initialize)
)
eng.pool.logger = Mock()
return eng
def test_cursor_explode(self):
db = self._fixture(False, False)
conn = db.connect()
result = conn.execute("select foo")
result.close()
conn.close()
eq_(
db.pool.logger.error.mock_calls,
[call("Error closing cursor", exc_info=True)],
)
def test_cursor_shutdown_in_initialize(self):
db = self._fixture(True, True)
assert_raises_message_context_ok(
exc.SAWarning, "Exception attempting to detect", db.connect
)
eq_(
db.pool.logger.error.mock_calls,
[call("Error closing cursor", exc_info=True)],
)
def _assert_invalidated(fn, *args):
try:
fn(*args)
assert False
except tsa.exc.DBAPIError as e:
if not e.connection_invalidated:
raise
class RealReconnectTest(fixtures.TestBase):
__backend__ = True
__requires__ = "graceful_disconnects", "ad_hoc_engines"
def setup(self):
self.engine = engines.reconnecting_engine()
def teardown(self):
self.engine.dispose()
def test_reconnect(self):
conn = self.engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.closed
self.engine.test_shutdown()
_assert_invalidated(conn.execute, select([1]))
assert not conn.closed
assert conn.invalidated
assert conn.invalidated
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.invalidated
# one more time
self.engine.test_shutdown()
_assert_invalidated(conn.execute, select([1]))
assert conn.invalidated
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.invalidated
conn.close()
def test_multiple_invalidate(self):
c1 = self.engine.connect()
c2 = self.engine.connect()
eq_(c1.execute(select([1])).scalar(), 1)
self.engine.test_shutdown()
_assert_invalidated(c1.execute, select([1]))
p2 = self.engine.pool
_assert_invalidated(c2.execute, select([1]))
# pool isn't replaced
assert self.engine.pool is p2
def test_branched_invalidate_branch_to_parent(self):
c1 = self.engine.connect()
with patch.object(self.engine.pool, "logger") as logger:
c1_branch = c1.connect()
eq_(c1_branch.execute(select([1])).scalar(), 1)
self.engine.test_shutdown()
_assert_invalidated(c1_branch.execute, select([1]))
assert c1.invalidated
assert c1_branch.invalidated
c1_branch._revalidate_connection()
assert not c1.invalidated
assert not c1_branch.invalidated
assert "Invalidate connection" in logger.mock_calls[0][1][0]
def test_branched_invalidate_parent_to_branch(self):
c1 = self.engine.connect()
c1_branch = c1.connect()
eq_(c1_branch.execute(select([1])).scalar(), 1)
self.engine.test_shutdown()
_assert_invalidated(c1.execute, select([1]))
assert c1.invalidated
assert c1_branch.invalidated
c1._revalidate_connection()
assert not c1.invalidated
assert not c1_branch.invalidated
def test_branch_invalidate_state(self):
c1 = self.engine.connect()
c1_branch = c1.connect()
eq_(c1_branch.execute(select([1])).scalar(), 1)
self.engine.test_shutdown()
_assert_invalidated(c1_branch.execute, select([1]))
assert not c1_branch.closed
assert not c1_branch._connection_is_valid
def test_ensure_is_disconnect_gets_connection(self):
def is_disconnect(e, conn, cursor):
# connection is still present
assert conn.connection is not None
# the error usually occurs on connection.cursor(),
# though MySQLdb we get a non-working cursor.
# assert cursor is None
self.engine.dialect.is_disconnect = is_disconnect
conn = self.engine.connect()
self.engine.test_shutdown()
with expect_warnings(
"An exception has occurred during handling .*", py2konly=True
):
assert_raises(tsa.exc.DBAPIError, conn.execute, select([1]))
def test_rollback_on_invalid_plain(self):
conn = self.engine.connect()
trans = conn.begin()
conn.invalidate()
trans.rollback()
@testing.requires.two_phase_transactions
def test_rollback_on_invalid_twophase(self):
conn = self.engine.connect()
trans = conn.begin_twophase()
conn.invalidate()
trans.rollback()
@testing.requires.savepoints
def test_rollback_on_invalid_savepoint(self):
conn = self.engine.connect()
conn.begin()
trans2 = conn.begin_nested()
conn.invalidate()
trans2.rollback()
def test_invalidate_twice(self):
conn = self.engine.connect()
conn.invalidate()
conn.invalidate()
@testing.skip_if(
[lambda: util.py3k, "oracle+cx_oracle"], "Crashes on py3k+cx_oracle"
)
def test_explode_in_initializer(self):
engine = engines.testing_engine()
def broken_initialize(connection):
connection.execute("select fake_stuff from _fake_table")
engine.dialect.initialize = broken_initialize
# raises a DBAPIError, not an AttributeError
assert_raises(exc.DBAPIError, engine.connect)
@testing.skip_if(
[lambda: util.py3k, "oracle+cx_oracle"], "Crashes on py3k+cx_oracle"
)
def test_explode_in_initializer_disconnect(self):
engine = engines.testing_engine()
def broken_initialize(connection):
connection.execute("select fake_stuff from _fake_table")
engine.dialect.initialize = broken_initialize
def is_disconnect(e, conn, cursor):
return True
engine.dialect.is_disconnect = is_disconnect
# invalidate() also doesn't screw up
assert_raises(exc.DBAPIError, engine.connect)
def test_null_pool(self):
engine = engines.reconnecting_engine(
options=dict(poolclass=pool.NullPool)
)
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.closed
engine.test_shutdown()
_assert_invalidated(conn.execute, select([1]))
assert not conn.closed
assert conn.invalidated
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.invalidated
def test_close(self):
conn = self.engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.closed
self.engine.test_shutdown()
_assert_invalidated(conn.execute, select([1]))
conn.close()
conn = self.engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
def test_with_transaction(self):
conn = self.engine.connect()
trans = conn.begin()
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.closed
self.engine.test_shutdown()
_assert_invalidated(conn.execute, select([1]))
assert not conn.closed
assert conn.invalidated
assert trans.is_active
assert_raises_message(
tsa.exc.StatementError,
"Can't reconnect until invalid transaction is rolled back",
conn.execute,
select([1]),
)
assert trans.is_active
assert_raises_message(
tsa.exc.InvalidRequestError,
"Can't reconnect until invalid transaction is rolled back",
trans.commit,
)
assert trans.is_active
trans.rollback()
assert not trans.is_active
assert conn.invalidated
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.invalidated
class RecycleTest(fixtures.TestBase):
__backend__ = True
def test_basic(self):
engine = engines.reconnecting_engine()
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
conn.close()
# set the pool recycle down to 1.
# we aren't doing this inline with the
# engine create since cx_oracle takes way
# too long to create the 1st connection and don't
# want to build a huge delay into this test.
engine.pool._recycle = 1
# kill the DB connection
engine.test_shutdown()
# wait until past the recycle period
time.sleep(2)
# can connect, no exception
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
conn.close()
class PrePingRealTest(fixtures.TestBase):
__backend__ = True
def test_pre_ping_db_is_restarted(self):
engine = engines.reconnecting_engine(options={"pool_pre_ping": True})
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
stale_connection = conn.connection.connection
conn.close()
engine.test_shutdown()
engine.test_restart()
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
conn.close()
def exercise_stale_connection():
curs = stale_connection.cursor()
curs.execute("select 1")
assert_raises(engine.dialect.dbapi.Error, exercise_stale_connection)
def test_pre_ping_db_stays_shutdown(self):
engine = engines.reconnecting_engine(options={"pool_pre_ping": True})
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
conn.close()
engine.test_shutdown(stop=True)
assert_raises(exc.DBAPIError, engine.connect)
class InvalidateDuringResultTest(fixtures.TestBase):
__backend__ = True
def setup(self):
self.engine = engines.reconnecting_engine()
self.meta = MetaData(self.engine)
table = Table(
"sometable",
self.meta,
Column("id", Integer, primary_key=True),
Column("name", String(50)),
)
self.meta.create_all()
table.insert().execute(
[{"id": i, "name": "row %d" % i} for i in range(1, 100)]
)
def teardown(self):
self.meta.drop_all()
self.engine.dispose()
@testing.crashes(
"oracle",
"cx_oracle 6 doesn't allow a close like this due to open cursors",
)
@testing.fails_if(
["+mysqlconnector", "+mysqldb", "+cymysql", "+pymysql", "+pg8000"],
"Buffers the result set and doesn't check for connection close",
)
def test_invalidate_on_results(self):
conn = self.engine.connect()
result = conn.execute("select * from sometable")
for x in range(20):
result.fetchone()
self.engine.test_shutdown()
_assert_invalidated(result.fetchone)
assert conn.invalidated