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from sqlalchemy.test.testing import eq_
import time
import weakref
from sqlalchemy import select, MetaData, Integer, String, pool
from sqlalchemy.test.schema import Table
from sqlalchemy.test.schema import Column
import sqlalchemy as tsa
from sqlalchemy.test import TestBase, testing, engines
from sqlalchemy.test.util import gc_collect
class MockDisconnect(Exception):
pass
class MockDBAPI(object):
def __init__(self):
self.paramstyle = 'named'
self.connections = weakref.WeakKeyDictionary()
def connect(self, *args, **kwargs):
return MockConnection(self)
def shutdown(self):
for c in self.connections:
c.explode[0] = True
Error = MockDisconnect
class MockConnection(object):
def __init__(self, dbapi):
dbapi.connections[self] = True
self.explode = [False]
def rollback(self):
pass
def commit(self):
pass
def cursor(self):
return MockCursor(self)
def close(self):
pass
class MockCursor(object):
def __init__(self, parent):
self.explode = parent.explode
self.description = ()
def execute(self, *args, **kwargs):
if self.explode[0]:
raise MockDisconnect("Lost the DB connection")
else:
return
def close(self):
pass
db, dbapi = None, None
class MockReconnectTest(TestBase):
def setup(self):
global db, dbapi
dbapi = MockDBAPI()
db = tsa.create_engine(
'postgresql://foo:bar@localhost/test',
module=dbapi, _initialize=False)
# monkeypatch disconnect checker
db.dialect.is_disconnect = lambda e: isinstance(e, MockDisconnect)
def test_reconnect(self):
"""test that an 'is_disconnect' condition will invalidate the
connection, and additionally dispose the previous connection
pool and recreate."""
pid = id(db.pool)
# make a connection
conn = db.connect()
# connection works
conn.execute(select([1]))
# create a second connection within the pool, which we'll ensure
# also goes away
conn2 = db.connect()
conn2.close()
# two connections opened total now
assert len(dbapi.connections) == 2
# set it to fail
dbapi.shutdown()
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError:
pass
# assert was invalidated
assert not conn.closed
assert conn.invalidated
# close shouldnt break
conn.close()
assert id(db.pool) != pid
# ensure all connections closed (pool was recycled)
gc_collect()
assert len(dbapi.connections) == 0
conn = db.connect()
conn.execute(select([1]))
conn.close()
assert len(dbapi.connections) == 1
def test_invalidate_trans(self):
conn = db.connect()
trans = conn.begin()
dbapi.shutdown()
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError:
pass
# assert was invalidated
gc_collect()
assert len(dbapi.connections) == 0
assert not conn.closed
assert conn.invalidated
assert trans.is_active
try:
conn.execute(select([1]))
assert False
except tsa.exc.InvalidRequestError, e:
assert str(e) \
== "Can't reconnect until invalid transaction is "\
"rolled back"
assert trans.is_active
try:
trans.commit()
assert False
except tsa.exc.InvalidRequestError, e:
assert str(e) \
== "Can't reconnect until invalid transaction is "\
"rolled back"
assert trans.is_active
trans.rollback()
assert not trans.is_active
conn.execute(select([1]))
assert not conn.invalidated
assert len(dbapi.connections) == 1
def test_conn_reusable(self):
conn = db.connect()
conn.execute(select([1]))
assert len(dbapi.connections) == 1
dbapi.shutdown()
# raises error
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError:
pass
assert not conn.closed
assert conn.invalidated
# ensure all connections closed (pool was recycled)
gc_collect()
assert len(dbapi.connections) == 0
# test reconnects
conn.execute(select([1]))
assert not conn.invalidated
assert len(dbapi.connections) == 1
class CursorErrTest(TestBase):
def setup(self):
global db, dbapi
class MDBAPI(MockDBAPI):
def connect(self, *args, **kwargs):
return MConn(self)
class MConn(MockConnection):
def cursor(self):
return MCursor(self)
class MCursor(MockCursor):
def close(self):
raise Exception("explode")
dbapi = MDBAPI()
db = tsa.create_engine(
'postgresql://foo:bar@localhost/test',
module=dbapi, _initialize=False)
def test_cursor_explode(self):
conn = db.connect()
result = conn.execute("select foo")
result.close()
conn.close()
def teardown(self):
db.dispose()
engine = None
class RealReconnectTest(TestBase):
def setup(self):
global engine
engine = engines.reconnecting_engine()
def teardown(self):
engine.dispose()
def test_reconnect(self):
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.closed
engine.test_shutdown()
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError, e:
if not e.connection_invalidated:
raise
assert not conn.closed
assert conn.invalidated
assert conn.invalidated
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.invalidated
# one more time
engine.test_shutdown()
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError, e:
if not e.connection_invalidated:
raise
assert conn.invalidated
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.invalidated
conn.close()
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()
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError, e:
if not e.connection_invalidated:
raise
assert not conn.closed
assert conn.invalidated
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.invalidated
def test_close(self):
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.closed
engine.test_shutdown()
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError, e:
if not e.connection_invalidated:
raise
conn.close()
conn = engine.connect()
eq_(conn.execute(select([1])).scalar(), 1)
def test_with_transaction(self):
conn = engine.connect()
trans = conn.begin()
eq_(conn.execute(select([1])).scalar(), 1)
assert not conn.closed
engine.test_shutdown()
try:
conn.execute(select([1]))
assert False
except tsa.exc.DBAPIError, e:
if not e.connection_invalidated:
raise
assert not conn.closed
assert conn.invalidated
assert trans.is_active
try:
conn.execute(select([1]))
assert False
except tsa.exc.InvalidRequestError, e:
assert str(e) \
== "Can't reconnect until invalid transaction is "\
"rolled back"
assert trans.is_active
try:
trans.commit()
assert False
except tsa.exc.InvalidRequestError, e:
assert str(e) \
== "Can't reconnect until invalid transaction is "\
"rolled back"
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(TestBase):
def test_basic(self):
for threadlocal in False, True:
engine = engines.reconnecting_engine(options={'pool_recycle'
: 1, 'pool_threadlocal': threadlocal})
conn = engine.contextual_connect()
eq_(conn.execute(select([1])).scalar(), 1)
conn.close()
engine.test_shutdown()
time.sleep(2)
conn = engine.contextual_connect()
eq_(conn.execute(select([1])).scalar(), 1)
conn.close()
meta, table, engine = None, None, None
class InvalidateDuringResultTest(TestBase):
def setup(self):
global meta, table, engine
engine = engines.reconnecting_engine()
meta = MetaData(engine)
table = Table('sometable', meta,
Column('id', Integer, primary_key=True),
Column('name', String(50)))
meta.create_all()
table.insert().execute(
[{'id':i, 'name':'row %d' % i} for i in range(1, 100)]
)
def teardown(self):
meta.drop_all()
engine.dispose()
@testing.fails_on('+mysqldb',
"Buffers the result set and doesn't check for "
"connection close")
@testing.fails_on('+pg8000',
"Buffers the result set and doesn't check for "
"connection close")
def test_invalidate_on_results(self):
conn = engine.connect()
result = conn.execute('select * from sometable')
for x in xrange(20):
result.fetchone()
engine.test_shutdown()
try:
print 'ghost result: %r' % result.fetchone()
assert False
except tsa.exc.DBAPIError, e:
if not e.connection_invalidated:
raise
assert conn.invalidated
|
