def test_socket_closed(self):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((client_context.host, client_context.port))
socket_checker = SocketChecker()
self.assertFalse(socket_checker.socket_closed(s))
s.close()
self.assertTrue(socket_checker.socket_closed(s))
def __init__(self, address, options, handshake=True):
"""
:Parameters:
- `address`: a (hostname, port) tuple
- `options`: a PoolOptions instance
- `handshake`: whether to call ismaster for each new SocketInfo
"""
# Check a socket's health with socket_closed() every once in a while.
# Can override for testing: 0 to always check, None to never check.
self._check_interval_seconds = 1
# LIFO pool. Sockets are ordered on idle time. Sockets claimed
# and returned to pool from the left side. Stale sockets removed
# from the right side.
self.sockets = collections.deque()
self.lock = threading.Lock()
self.active_sockets = 0
# Monotonically increasing connection ID required for CMAP Events.
self.next_connection_id = 1
self.closed = False
# Track whether the sockets in this pool are writeable or not.
self.is_writable = None
# Keep track of resets, so we notice sockets created before the most
# recent reset and close them.
self.generation = 0
self.pid = os.getpid()
self.address = address
self.opts = options
self.handshake = handshake
# Don't publish events in Monitor pools.
self.enabled_for_cmap = (self.handshake
and self.opts.event_listeners is not None and
self.opts.event_listeners.enabled_for_cmap)
if (self.opts.wait_queue_multiple is None
or self.opts.max_pool_size is None):
max_waiters = None
else:
max_waiters = (self.opts.max_pool_size *
self.opts.wait_queue_multiple)
self._socket_semaphore = thread_util.create_semaphore(
self.opts.max_pool_size, max_waiters)
self.socket_checker = SocketChecker()
if self.enabled_for_cmap:
self.opts.event_listeners.publish_pool_created(
self.address, self.opts.non_default_options)
def test_socket_closed_thread_safe(self):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((client_context.host, client_context.port))
self.addCleanup(s.close)
socket_checker = SocketChecker()
def check_socket():
for _ in range(1000):
self.assertFalse(socket_checker.socket_closed(s))
threads = []
for i in range(3):
thread = threading.Thread(target=check_socket)
thread.start()
threads.append(thread)
for thread in threads:
thread.join()
class Pool:
def __init__(self, address, options, handshake=True):
"""
:Parameters:
- `address`: a (hostname, port) tuple
- `options`: a PoolOptions instance
- `handshake`: whether to call ismaster for each new SocketInfo
"""
# Check a socket's health with socket_closed() every once in a while.
# Can override for testing: 0 to always check, None to never check.
self._check_interval_seconds = 1
# LIFO pool. Sockets are ordered on idle time. Sockets claimed
# and returned to pool from the left side. Stale sockets removed
# from the right side.
self.sockets = collections.deque()
self.lock = threading.Lock()
self.active_sockets = 0
# Monotonically increasing connection ID required for CMAP Events.
self.next_connection_id = 1
self.closed = False
# Track whether the sockets in this pool are writeable or not.
self.is_writable = None
# Keep track of resets, so we notice sockets created before the most
# recent reset and close them.
self.generation = 0
self.pid = os.getpid()
self.address = address
self.opts = options
self.handshake = handshake
# Don't publish events in Monitor pools.
self.enabled_for_cmap = (self.handshake
and self.opts.event_listeners is not None and
self.opts.event_listeners.enabled_for_cmap)
if (self.opts.wait_queue_multiple is None
or self.opts.max_pool_size is None):
max_waiters = None
else:
max_waiters = (self.opts.max_pool_size *
self.opts.wait_queue_multiple)
self._socket_semaphore = thread_util.create_semaphore(
self.opts.max_pool_size, max_waiters)
self.socket_checker = SocketChecker()
if self.enabled_for_cmap:
self.opts.event_listeners.publish_pool_created(
self.address, self.opts.non_default_options)
def _reset(self, close):
with self.lock:
if self.closed:
return
self.generation += 1
self.pid = os.getpid()
sockets, self.sockets = self.sockets, collections.deque()
self.active_sockets = 0
if close:
self.closed = True
listeners = self.opts.event_listeners
# CMAP spec says that close() MUST close sockets before publishing the
# PoolClosedEvent but that reset() SHOULD close sockets *after*
# publishing the PoolClearedEvent.
if close:
for sock_info in sockets:
sock_info.close_socket(ConnectionClosedReason.POOL_CLOSED)
if self.enabled_for_cmap:
listeners.publish_pool_closed(self.address)
else:
if self.enabled_for_cmap:
listeners.publish_pool_cleared(self.address)
for sock_info in sockets:
sock_info.close_socket(ConnectionClosedReason.STALE)
def update_is_writable(self, is_writable):
"""Updates the is_writable attribute on all sockets currently in the
Pool.
"""
self.is_writable = is_writable
with self.lock:
for socket in self.sockets:
socket.update_is_writable(self.is_writable)
def reset(self):
self._reset(close=False)
def close(self):
self._reset(close=True)
def remove_stale_sockets(self, reference_generation):
"""Removes stale sockets then adds new ones if pool is too small and
has not been reset. The `reference_generation` argument specifies the
`generation` at the point in time this operation was requested on the
pool.
"""
if self.opts.max_idle_time_seconds is not None:
with self.lock:
while (self.sockets and self.sockets[-1].idle_time_seconds() >
self.opts.max_idle_time_seconds):
sock_info = self.sockets.pop()
sock_info.close_socket(ConnectionClosedReason.IDLE)
while True:
with self.lock:
if (len(self.sockets) + self.active_sockets >=
self.opts.min_pool_size):
# There are enough sockets in the pool.
break
# We must acquire the semaphore to respect max_pool_size.
if not self._socket_semaphore.acquire(False):
break
try:
sock_info = self.connect()
with self.lock:
# Close connection and return if the pool was reset during
# socket creation or while acquiring the pool lock.
if self.generation != reference_generation:
sock_info.close_socket(ConnectionClosedReason.STALE)
break
self.sockets.appendleft(sock_info)
finally:
self._socket_semaphore.release()
def connect(self):
"""Connect to Mongo and return a new SocketInfo.
Can raise ConnectionFailure or CertificateError.
Note that the pool does not keep a reference to the socket -- you
must call return_socket() when you're done with it.
"""
with self.lock:
conn_id = self.next_connection_id
self.next_connection_id += 1
listeners = self.opts.event_listeners
if self.enabled_for_cmap:
listeners.publish_connection_created(self.address, conn_id)
sock = None
try:
sock = _configured_socket(self.address, self.opts)
except socket.error as error:
if sock is not None:
sock.close()
if self.enabled_for_cmap:
listeners.publish_connection_closed(
self.address, conn_id, ConnectionClosedReason.ERROR)
_raise_connection_failure(self.address, error)
sock_info = SocketInfo(sock, self, self.address, conn_id)
if self.handshake:
sock_info.ismaster(self.opts.metadata, None)
self.is_writable = sock_info.is_writable
return sock_info
@contextlib.contextmanager
def get_socket(self, all_credentials, checkout=False):
"""Get a socket from the pool. Use with a "with" statement.
Returns a :class:`SocketInfo` object wrapping a connected
:class:`socket.socket`.
This method should always be used in a with-statement::
with pool.get_socket(credentials, checkout) as socket_info:
socket_info.send_message(msg)
data = socket_info.receive_message(op_code, request_id)
The socket is logged in or out as needed to match ``all_credentials``
using the correct authentication mechanism for the server's wire
protocol version.
Can raise ConnectionFailure or OperationFailure.
:Parameters:
- `all_credentials`: dict, maps auth source to MongoCredential.
- `checkout` (optional): keep socket checked out.
"""
listeners = self.opts.event_listeners
if self.enabled_for_cmap:
listeners.publish_connection_check_out_started(self.address)
# First get a socket, then attempt authentication. Simplifies
# semaphore management in the face of network errors during auth.
sock_info = self._get_socket_no_auth()
checked_auth = False
try:
sock_info.check_auth(all_credentials)
checked_auth = True
if self.enabled_for_cmap:
listeners.publish_connection_checked_out(
self.address, sock_info.id)
yield sock_info
except:
# Exception in caller. Decrement semaphore.
self.return_socket(sock_info, publish_checkin=checked_auth)
if self.enabled_for_cmap and not checked_auth:
self.opts.event_listeners.publish_connection_check_out_failed(
self.address, ConnectionCheckOutFailedReason.CONN_ERROR)
raise
else:
if not checkout:
self.return_socket(sock_info)
def _get_socket_no_auth(self):
"""Get or create a SocketInfo. Can raise ConnectionFailure."""
# We use the pid here to avoid issues with fork / multiprocessing.
# See test.test_client:TestClient.test_fork for an example of
# what could go wrong otherwise
if self.pid != os.getpid():
self.reset()
if self.closed:
if self.enabled_for_cmap:
self.opts.event_listeners.publish_connection_check_out_failed(
self.address, ConnectionCheckOutFailedReason.POOL_CLOSED)
raise _PoolClosedError(
'Attempted to check out a connection from closed connection '
'pool')
# Get a free socket or create one.
if not self._socket_semaphore.acquire(True,
self.opts.wait_queue_timeout):
self._raise_wait_queue_timeout()
with self.lock:
self.active_sockets += 1
# We've now acquired the semaphore and must release it on error.
try:
sock_info = None
while sock_info is None:
try:
with self.lock:
sock_info = self.sockets.popleft()
except IndexError:
# Can raise ConnectionFailure or CertificateError.
sock_info = self.connect()
else:
if self._perished(sock_info):
sock_info = None
except Exception:
self._socket_semaphore.release()
with self.lock:
self.active_sockets -= 1
if self.enabled_for_cmap:
self.opts.event_listeners.publish_connection_check_out_failed(
self.address, ConnectionCheckOutFailedReason.CONN_ERROR)
raise
return sock_info
def return_socket(self, sock_info, publish_checkin=True):
"""Return the socket to the pool, or if it's closed discard it.
:Parameters:
- `sock_info`: The socket to check into the pool.
- `publish_checkin`: If False, a ConnectionCheckedInEvent will not
be published.
"""
listeners = self.opts.event_listeners
if self.enabled_for_cmap and publish_checkin:
listeners.publish_connection_checked_in(self.address, sock_info.id)
if self.pid != os.getpid():
self.reset()
else:
if self.closed:
sock_info.close_socket(ConnectionClosedReason.POOL_CLOSED)
elif not sock_info.closed:
with self.lock:
# Hold the lock to ensure this section does not race with
# Pool.reset().
if sock_info.generation != self.generation:
sock_info.close_socket(ConnectionClosedReason.STALE)
else:
sock_info.update_last_checkin_time()
sock_info.update_is_writable(self.is_writable)
self.sockets.appendleft(sock_info)
self._socket_semaphore.release()
with self.lock:
self.active_sockets -= 1
def _perished(self, sock_info):
"""Return True and close the connection if it is "perished".
This side-effecty function checks if this socket has been idle for
for longer than the max idle time, or if the socket has been closed by
some external network error, or if the socket's generation is outdated.
Checking sockets lets us avoid seeing *some*
:class:`~pymongo.errors.AutoReconnect` exceptions on server
hiccups, etc. We only check if the socket was closed by an external
error if it has been > 1 second since the socket was checked into the
pool, to keep performance reasonable - we can't avoid AutoReconnects
completely anyway.
"""
idle_time_seconds = sock_info.idle_time_seconds()
# If socket is idle, open a new one.
if (self.opts.max_idle_time_seconds is not None
and idle_time_seconds > self.opts.max_idle_time_seconds):
sock_info.close_socket(ConnectionClosedReason.IDLE)
return True
if (self._check_interval_seconds is not None
and (0 == self._check_interval_seconds
or idle_time_seconds > self._check_interval_seconds)):
if self.socket_checker.socket_closed(sock_info.sock):
sock_info.close_socket(ConnectionClosedReason.ERROR)
return True
if sock_info.generation != self.generation:
sock_info.close_socket(ConnectionClosedReason.STALE)
return True
return False
def _raise_wait_queue_timeout(self):
listeners = self.opts.event_listeners
if self.enabled_for_cmap:
listeners.publish_connection_check_out_failed(
self.address, ConnectionCheckOutFailedReason.TIMEOUT)
raise ConnectionFailure(
'Timed out while checking out a connection from connection pool '
'with max_size %r and wait_queue_timeout %r' %
(self.opts.max_pool_size, self.opts.wait_queue_timeout))
def __del__(self):
# Avoid ResourceWarnings in Python 3
# Close all sockets without calling reset() or close() because it is
# not safe to acquire a lock in __del__.
for sock_info in self.sockets:
sock_info.close_socket(None)
def test_socket_checker(self):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((client_context.host, client_context.port))
socket_checker = SocketChecker()
# Socket has nothing to read.
self.assertFalse(socket_checker.select(s, read=True))
self.assertFalse(socket_checker.select(s, read=True, timeout=0))
self.assertFalse(socket_checker.select(s, read=True, timeout=.05))
# Socket is writable.
self.assertTrue(socket_checker.select(s, write=True, timeout=None))
self.assertTrue(socket_checker.select(s, write=True))
self.assertTrue(socket_checker.select(s, write=True, timeout=0))
self.assertTrue(socket_checker.select(s, write=True, timeout=.05))
# Make the socket readable
_, msg, _ = message._query(
0, 'admin.$cmd', 0, -1, SON([('isMaster', 1)]), None,
DEFAULT_CODEC_OPTIONS)
s.sendall(msg)
# Block until the socket is readable.
self.assertTrue(socket_checker.select(s, read=True, timeout=None))
self.assertTrue(socket_checker.select(s, read=True))
self.assertTrue(socket_checker.select(s, read=True, timeout=0))
self.assertTrue(socket_checker.select(s, read=True, timeout=.05))
# Socket is still writable.
self.assertTrue(socket_checker.select(s, write=True, timeout=None))
self.assertTrue(socket_checker.select(s, write=True))
self.assertTrue(socket_checker.select(s, write=True, timeout=0))
self.assertTrue(socket_checker.select(s, write=True, timeout=.05))
s.close()
self.assertTrue(socket_checker.socket_closed(s))
