class BoltConnector(Connector):
scheme = "bolt"
@property
def server_agent(self):
cx = self.pool.acquire()
try:
return cx.server.agent
finally:
self.pool.release(cx)
def open(self, cx_data):
def connector(address_, **kwargs):
return connect(address_, auth=cx_data["auth"], **kwargs)
address = (cx_data["host"], cx_data["port"])
self.pool = ConnectionPool(connector, address)
def close(self):
self.pool.close()
def _run_1(self, statement, parameters, graph, keys, entities):
cx = self.pool.acquire()
hydrator = PackStreamHydrator(version=cx.protocol_version,
graph=graph,
keys=keys,
entities=entities)
dehydrated_parameters = hydrator.dehydrate(parameters)
result = CypherResult(on_more=cx.fetch,
on_done=lambda: self.pool.release(cx))
result.update_metadata({"connection": self.connection_data})
def update_metadata_with_keys(metadata):
result.update_metadata(metadata)
hydrator.keys = result.keys()
cx.run(statement,
dehydrated_parameters or {},
on_success=update_metadata_with_keys,
on_failure=self._fail)
cx.pull_all(on_records=lambda records: result.append_records(
map(hydrator.hydrate, records)),
on_success=result.update_metadata,
on_failure=self._fail,
on_summary=result.done)
cx.send()
cx.fetch()
return result
def _run_in_tx(self, statement, parameters, tx, graph, keys, entities):
self._assert_valid_tx(tx)
def fetch():
tx.fetch()
def fail(metadata):
self.transactions.remove(tx)
self.pool.release(tx)
self._fail(metadata)
hydrator = PackStreamHydrator(version=tx.protocol_version,
graph=graph,
keys=keys,
entities=entities)
dehydrated_parameters = hydrator.dehydrate(parameters)
result = CypherResult(on_more=fetch)
result.update_metadata({"connection": self.connection_data})
def update_metadata_with_keys(metadata):
result.update_metadata(metadata)
hydrator.keys = result.keys()
tx.run(statement,
dehydrated_parameters or {},
on_success=update_metadata_with_keys,
on_failure=fail)
tx.pull_all(on_records=lambda records: result.append_records(
map(hydrator.hydrate, records)),
on_success=result.update_metadata,
on_failure=fail,
on_summary=result.done)
tx.send()
result.keys() # force receipt of RUN summary, to detect any errors
return result
@classmethod
def _fail(cls, metadata):
from py2neo.database import GraphError
raise GraphError.hydrate(metadata)
def run(self,
statement,
parameters=None,
tx=None,
graph=None,
keys=None,
entities=None):
if tx is None:
return self._run_1(statement, parameters, graph, keys, entities)
else:
return self._run_in_tx(statement, parameters, tx, graph, keys,
entities)
def begin(self):
tx = self.pool.acquire()
tx.begin()
self.transactions.add(tx)
return tx
def commit(self, tx):
self._assert_valid_tx(tx)
self.transactions.remove(tx)
tx.commit()
tx.sync()
self.pool.release(tx)
def rollback(self, tx):
self._assert_valid_tx(tx)
self.transactions.remove(tx)
tx.rollback()
tx.sync()
self.pool.release(tx)
def sync(self, cx):
cx.sync()
class ConnectionPoolTestCase(TestCase):
def setUp(self):
self.pool = ConnectionPool(connector, ("127.0.0.1", 7687))
def tearDown(self):
self.pool.close()
def assert_pool_size(self,
address,
expected_active,
expected_inactive,
pool=None):
if pool is None:
pool = self.pool
try:
connections = pool.connections[address]
except KeyError:
self.assertEqual(0, expected_active)
self.assertEqual(0, expected_inactive)
else:
self.assertEqual(expected_active,
len([cx for cx in connections if cx.in_use]))
self.assertEqual(expected_inactive,
len([cx for cx in connections if not cx.in_use]))
def test_can_acquire(self):
address = ("127.0.0.1", 7687)
connection = self.pool.acquire_direct(address)
assert connection.address == address
self.assert_pool_size(address, 1, 0)
def test_can_acquire_twice(self):
address = ("127.0.0.1", 7687)
connection_1 = self.pool.acquire_direct(address)
connection_2 = self.pool.acquire_direct(address)
assert connection_1.address == address
assert connection_2.address == address
assert connection_1 is not connection_2
self.assert_pool_size(address, 2, 0)
def test_can_acquire_two_addresses(self):
address_1 = ("127.0.0.1", 7687)
address_2 = ("127.0.0.1", 7474)
connection_1 = self.pool.acquire_direct(address_1)
connection_2 = self.pool.acquire_direct(address_2)
assert connection_1.address == address_1
assert connection_2.address == address_2
self.assert_pool_size(address_1, 1, 0)
self.assert_pool_size(address_2, 1, 0)
def test_can_acquire_and_release(self):
address = ("127.0.0.1", 7687)
connection = self.pool.acquire_direct(address)
self.assert_pool_size(address, 1, 0)
self.pool.release(connection)
self.assert_pool_size(address, 0, 1)
def test_releasing_twice(self):
address = ("127.0.0.1", 7687)
connection = self.pool.acquire_direct(address)
self.pool.release(connection)
self.assert_pool_size(address, 0, 1)
self.pool.release(connection)
self.assert_pool_size(address, 0, 1)
def test_cannot_acquire_after_close(self):
with ConnectionPool(lambda a: QuickConnection(FakeSocket(a)),
()) as pool:
pool.close()
with self.assertRaises(ServiceUnavailable):
_ = pool.acquire_direct("X")
def test_in_use_count(self):
address = ("127.0.0.1", 7687)
self.assertEqual(self.pool.in_use_connection_count(address), 0)
connection = self.pool.acquire_direct(address)
self.assertEqual(self.pool.in_use_connection_count(address), 1)
self.pool.release(connection)
self.assertEqual(self.pool.in_use_connection_count(address), 0)
def test_max_conn_pool_size(self):
with ConnectionPool(connector, (),
max_connection_pool_size=1,
connection_acquisition_timeout=0) as pool:
address = ("127.0.0.1", 7687)
pool.acquire_direct(address)
self.assertEqual(pool.in_use_connection_count(address), 1)
with self.assertRaises(ClientError):
pool.acquire_direct(address)
self.assertEqual(pool.in_use_connection_count(address), 1)
def test_multithread(self):
with ConnectionPool(connector, (),
max_connection_pool_size=5,
connection_acquisition_timeout=10) as pool:
address = ("127.0.0.1", 7687)
releasing_event = Event()
# We start 10 threads to compete connections from pool with size of 5
threads = []
for i in range(10):
t = Thread(target=acquire_release_conn,
args=(pool, address, releasing_event))
t.start()
threads.append(t)
# The pool size should be 5, all are in-use
self.assert_pool_size(address, 5, 0, pool)
# Now we allow thread to release connections they obtained from pool
releasing_event.set()
# wait for all threads to release connections back to pool
for t in threads:
t.join()
# The pool size is still 5, but all are free
self.assert_pool_size(address, 0, 5, pool)