"""0MQ Socket pure Python methods."""
# Copyright (C) PyZMQ Developers
# Distributed under the terms of the Modified BSD License.
import errno
import pickle
import random
import sys
from typing import (
Any,
Callable,
Dict,
Generic,
List,
Optional,
Sequence,
Type,
TypeVar,
Union,
cast,
overload,
)
from warnings import warn
import zmq
from zmq._typing import Literal
from zmq.backend import Socket as SocketBase
from zmq.error import ZMQBindError, ZMQError
from zmq.utils import jsonapi
from zmq.utils.interop import cast_int_addr
from ..constants import SocketOption, SocketType, _OptType
from .attrsettr import AttributeSetter
from .poll import Poller
try:
DEFAULT_PROTOCOL = pickle.DEFAULT_PROTOCOL
except AttributeError:
DEFAULT_PROTOCOL = pickle.HIGHEST_PROTOCOL
T = TypeVar("T", bound="Socket")
class _SocketContext(Generic[T]):
"""Context Manager for socket bind/unbind"""
socket: T
kind: str
addr: str
def __repr__(self):
return f"<SocketContext({self.kind}={self.addr!r})>"
def __init__(self: "_SocketContext[T]", socket: T, kind: str, addr: str):
assert kind in {"bind", "connect"}
self.socket = socket
self.kind = kind
self.addr = addr
def __enter__(self: "_SocketContext[T]") -> T:
return self.socket
def __exit__(self, *args):
if self.socket.closed:
return
if self.kind == "bind":
self.socket.unbind(self.addr)
elif self.kind == "connect":
self.socket.disconnect(self.addr)
ST = TypeVar("ST")
class Socket(SocketBase, AttributeSetter, Generic[ST]):
"""The ZMQ socket object
To create a Socket, first create a Context::
ctx = zmq.Context.instance()
then call ``ctx.socket(socket_type)``::
s = ctx.socket(zmq.ROUTER)
.. versionadded:: 25
Sockets can now be shadowed by passing another Socket.
This helps in creating an async copy of a sync socket or vice versa::
s = zmq.Socket(async_socket)
Which previously had to be::
s = zmq.Socket.shadow(async_socket.underlying)
"""
_shadow = False
_shadow_obj = None
_monitor_socket = None
_type_name = 'UNKNOWN'
@overload
def __init__(
self: "Socket[bytes]",
ctx_or_socket: "zmq.Context",
socket_type: int,
*,
copy_threshold: Optional[int] = None,
):
...
@overload
def __init__(
self: "Socket[bytes]",
*,
shadow: Union["Socket", int],
copy_threshold: Optional[int] = None,
):
...
@overload
def __init__(
self: "Socket[bytes]",
ctx_or_socket: "Socket",
):
...
def __init__(
self: "Socket[bytes]",
ctx_or_socket: Optional[Union["zmq.Context", "Socket"]] = None,
socket_type: int = 0,
*,
shadow: Union["Socket", int] = 0,
copy_threshold: Optional[int] = None,
):
if isinstance(ctx_or_socket, zmq.Socket):
# positional Socket(other_socket)
shadow = ctx_or_socket
ctx_or_socket = None
shadow_address: int = 0
if shadow:
self._shadow = True
# hold a reference to the shadow object
self._shadow_obj = shadow
if not isinstance(shadow, int):
try:
shadow = cast(int, shadow.underlying)
except AttributeError:
pass
shadow_address = cast_int_addr(shadow)
else:
self._shadow = False
super().__init__(
ctx_or_socket,
socket_type,
shadow=shadow_address,
copy_threshold=copy_threshold,
)
try:
socket_type = cast(int, self.get(zmq.TYPE))
except Exception:
pass
else:
try:
self.__dict__["type"] = stype = SocketType(socket_type)
except ValueError:
self._type_name = str(socket_type)
else:
self._type_name = stype.name
def __del__(self):
if not self._shadow and not self.closed:
if warn is not None:
# warn can be None during process teardown
warn(
f"Unclosed socket {self}",
ResourceWarning,
stacklevel=2,
source=self,
)
self.close()
_repr_cls = "zmq.Socket"
def __repr__(self):
cls = self.__class__
# look up _repr_cls on exact class, not inherited
_repr_cls = cls.__dict__.get("_repr_cls", None)
if _repr_cls is None:
_repr_cls = f"{cls.__module__}.{cls.__name__}"
closed = ' closed' if self._closed else ''
return f"<{_repr_cls}(zmq.{self._type_name}) at {hex(id(self))}{closed}>"
# socket as context manager:
def __enter__(self: T) -> T:
"""Sockets are context managers
.. versionadded:: 14.4
"""
return self
def __exit__(self, *args, **kwargs):
self.close()
# -------------------------------------------------------------------------
# Socket creation
# -------------------------------------------------------------------------
def __copy__(self: T, memo=None) -> T:
"""Copying a Socket creates a shadow copy"""
return self.__class__.shadow(self.underlying)
__deepcopy__ = __copy__
@classmethod
def shadow(cls: Type[T], address: Union[int, "zmq.Socket"]) -> T:
"""Shadow an existing libzmq socket
address is a zmq.Socket or an integer (or FFI pointer)
representing the address of the libzmq socket.
.. versionadded:: 14.1
.. versionadded:: 25
Support for shadowing `zmq.Socket` objects,
instead of just integer addresses.
"""
return cls(shadow=address)
def close(self, linger=None) -> None:
"""
Close the socket.
If linger is specified, LINGER sockopt will be set prior to closing.
Note: closing a zmq Socket may not close the underlying sockets
if there are undelivered messages.
Only after all messages are delivered or discarded by reaching the socket's LINGER timeout
(default: forever)
will the underlying sockets be closed.
This can be called to close the socket by hand. If this is not
called, the socket will automatically be closed when it is
garbage collected,
in which case you may see a ResourceWarning about the unclosed socket.
"""
if self.context:
self.context._rm_socket(self)
super().close(linger=linger)
# -------------------------------------------------------------------------
# Connect/Bind context managers
# -------------------------------------------------------------------------
def _connect_cm(self: T, addr: str) -> _SocketContext[T]:
"""Context manager to disconnect on exit
.. versionadded:: 20.0
"""
return _SocketContext(self, 'connect', addr)
def _bind_cm(self: T, addr: str) -> _SocketContext[T]:
"""Context manager to unbind on exit
.. versionadded:: 20.0
"""
return _SocketContext(self, 'bind', addr)
def bind(self: T, addr: str) -> _SocketContext[T]:
"""s.bind(addr)
Bind the socket to an address.
This causes the socket to listen on a network port. Sockets on the
other side of this connection will use ``Socket.connect(addr)`` to
connect to this socket.
Returns a context manager which will call unbind on exit.
.. versionadded:: 20.0
Can be used as a context manager.
Parameters
----------
addr : str
The address string. This has the form 'protocol://interface:port',
for example 'tcp://127.0.0.1:5555'. Protocols supported include
tcp, udp, pgm, epgm, inproc and ipc. If the address is unicode, it is
encoded to utf-8 first.
"""
try:
super().bind(addr)
except ZMQError as e:
e.strerror += f" (addr={addr!r})"
raise
return self._bind_cm(addr)
def connect(self: T, addr: str) -> _SocketContext[T]:
"""s.connect(addr)
Connect to a remote 0MQ socket.
Returns a context manager which will call disconnect on exit.
.. versionadded:: 20.0
Can be used as a context manager.
Parameters
----------
addr : str
The address string. This has the form 'protocol://interface:port',
for example 'tcp://127.0.0.1:5555'. Protocols supported are
tcp, udp, pgm, inproc and ipc. If the address is unicode, it is
encoded to utf-8 first.
"""
try:
super().connect(addr)
except ZMQError as e:
e.strerror += f" (addr={addr!r})"
raise
return self._connect_cm(addr)
# -------------------------------------------------------------------------
# Deprecated aliases
# -------------------------------------------------------------------------
@property
def socket_type(self) -> int:
warn("Socket.socket_type is deprecated, use Socket.type", DeprecationWarning)
return cast(int, self.type)
# -------------------------------------------------------------------------
# Hooks for sockopt completion
# -------------------------------------------------------------------------
def __dir__(self):
keys = dir(self.__class__)
keys.extend(SocketOption.__members__)
return keys
# -------------------------------------------------------------------------
# Getting/Setting options
# -------------------------------------------------------------------------
setsockopt = SocketBase.set
getsockopt = SocketBase.get
def __setattr__(self, key, value):
"""Override to allow setting zmq.[UN]SUBSCRIBE even though we have a subscribe method"""
if key in self.__dict__:
object.__setattr__(self, key, value)
return
_key = key.lower()
if _key in ('subscribe', 'unsubscribe'):
if isinstance(value, str):
value = value.encode('utf8')
if _key == 'subscribe':
self.set(zmq.SUBSCRIBE, value)
else:
self.set(zmq.UNSUBSCRIBE, value)
return
super().__setattr__(key, value)
def fileno(self) -> int:
"""Return edge-triggered file descriptor for this socket.
This is a read-only edge-triggered file descriptor for both read and write events on this socket.
It is important that all available events be consumed when an event is detected,
otherwise the read event will not trigger again.
.. versionadded:: 17.0
"""
return self.FD
def subscribe(self, topic: Union[str, bytes]) -> None:
"""Subscribe to a topic
Only for SUB sockets.
.. versionadded:: 15.3
"""
if isinstance(topic, str):
topic = topic.encode('utf8')
self.set(zmq.SUBSCRIBE, topic)
def unsubscribe(self, topic: Union[str, bytes]) -> None:
"""Unsubscribe from a topic
Only for SUB sockets.
.. versionadded:: 15.3
"""
if isinstance(topic, str):
topic = topic.encode('utf8')
self.set(zmq.UNSUBSCRIBE, topic)
def set_string(self, option: int, optval: str, encoding='utf-8') -> None:
"""Set socket options with a unicode object.
This is simply a wrapper for setsockopt to protect from encoding ambiguity.
See the 0MQ documentation for details on specific options.
Parameters
----------
option : int
The name of the option to set. Can be any of: SUBSCRIBE,
UNSUBSCRIBE, IDENTITY
optval : str
The value of the option to set.
encoding : str
The encoding to be used, default is utf8
"""
if not isinstance(optval, str):
raise TypeError(f"strings only, not {type(optval)}: {optval!r}")
return self.set(option, optval.encode(encoding))
setsockopt_unicode = setsockopt_string = set_string
def get_string(self, option: int, encoding='utf-8') -> str:
"""Get the value of a socket option.
See the 0MQ documentation for details on specific options.
Parameters
----------
option : int
The option to retrieve.
Returns
-------
optval : str
The value of the option as a unicode string.
"""
if SocketOption(option)._opt_type != _OptType.bytes:
raise TypeError(f"option {option} will not return a string to be decoded")
return cast(bytes, self.get(option)).decode(encoding)
getsockopt_unicode = getsockopt_string = get_string
def bind_to_random_port(
self: T,
addr: str,
min_port: int = 49152,
max_port: int = 65536,
max_tries: int = 100,
) -> int:
"""Bind this socket to a random port in a range.
If the port range is unspecified, the system will choose the port.
Parameters
----------
addr : str
The address string without the port to pass to ``Socket.bind()``.
min_port : int, optional
The minimum port in the range of ports to try (inclusive).
max_port : int, optional
The maximum port in the range of ports to try (exclusive).
max_tries : int, optional
The maximum number of bind attempts to make.
Returns
-------
port : int
The port the socket was bound to.
Raises
------
ZMQBindError
if `max_tries` reached before successful bind
"""
if (
(zmq.zmq_version_info() >= (3, 2))
and min_port == 49152
and max_port == 65536
):
# if LAST_ENDPOINT is supported, and min_port / max_port weren't specified,
# we can bind to port 0 and let the OS do the work
self.bind("%s:*" % addr)
url = cast(bytes, self.last_endpoint).decode('ascii', 'replace')
_, port_s = url.rsplit(':', 1)
return int(port_s)
for i in range(max_tries):
try:
port = random.randrange(min_port, max_port)
self.bind(f'{addr}:{port}')
except ZMQError as exception:
en = exception.errno
if en == zmq.EADDRINUSE:
continue
elif sys.platform == 'win32' and en == errno.EACCES:
continue
else:
raise
else:
return port
raise ZMQBindError("Could not bind socket to random port.")
def get_hwm(self) -> int:
"""Get the High Water Mark.
On libzmq ≥ 3, this gets SNDHWM if available, otherwise RCVHWM
"""
major = zmq.zmq_version_info()[0]
if major >= 3:
# return sndhwm, fallback on rcvhwm
try:
return cast(int, self.get(zmq.SNDHWM))
except zmq.ZMQError:
pass
return cast(int, self.get(zmq.RCVHWM))
else:
return cast(int, self.get(zmq.HWM))
def set_hwm(self, value: int) -> None:
"""Set the High Water Mark.
On libzmq ≥ 3, this sets both SNDHWM and RCVHWM
.. warning::
New values only take effect for subsequent socket
bind/connects.
"""
major = zmq.zmq_version_info()[0]
if major >= 3:
raised = None
try:
self.sndhwm = value
except Exception as e:
raised = e
try:
self.rcvhwm = value
except Exception as e:
raised = e
if raised:
raise raised
else:
self.set(zmq.HWM, value)
hwm = property(
get_hwm,
set_hwm,
None,
"""Property for High Water Mark.
Setting hwm sets both SNDHWM and RCVHWM as appropriate.
It gets SNDHWM if available, otherwise RCVHWM.
""",
)
# -------------------------------------------------------------------------
# Sending and receiving messages
# -------------------------------------------------------------------------
@overload
def send(
self,
data: Any,
flags: int = ...,
copy: bool = ...,
*,
track: Literal[True],
routing_id: Optional[int] = ...,
group: Optional[str] = ...,
) -> "zmq.MessageTracker":
...
@overload
def send(
self,
data: Any,
flags: int = ...,
copy: bool = ...,
*,
track: Literal[False],
routing_id: Optional[int] = ...,
group: Optional[str] = ...,
) -> None:
...
@overload
def send(
self,
data: Any,
flags: int = ...,
*,
copy: bool = ...,
routing_id: Optional[int] = ...,
group: Optional[str] = ...,
) -> None:
...
@overload
def send(
self,
data: Any,
flags: int = ...,
copy: bool = ...,
track: bool = ...,
routing_id: Optional[int] = ...,
group: Optional[str] = ...,
) -> Optional["zmq.MessageTracker"]:
...
def send(
self,
data: Any,
flags: int = 0,
copy: bool = True,
track: bool = False,
routing_id: Optional[int] = None,
group: Optional[str] = None,
) -> Optional["zmq.MessageTracker"]:
"""Send a single zmq message frame on this socket.
This queues the message to be sent by the IO thread at a later time.
With flags=NOBLOCK, this raises :class:`ZMQError` if the queue is full;
otherwise, this waits until space is available.
See :class:`Poller` for more general non-blocking I/O.
Parameters
----------
data : bytes, Frame, memoryview
The content of the message. This can be any object that provides
the Python buffer API (i.e. `memoryview(data)` can be called).
flags : int
0, NOBLOCK, SNDMORE, or NOBLOCK|SNDMORE.
copy : bool
Should the message be sent in a copying or non-copying manner.
track : bool
Should the message be tracked for notification that ZMQ has
finished with it? (ignored if copy=True)
routing_id : int
For use with SERVER sockets
group : str
For use with RADIO sockets
Returns
-------
None : if `copy` or not track
None if message was sent, raises an exception otherwise.
MessageTracker : if track and not copy
a MessageTracker object, whose `pending` property will
be True until the send is completed.
Raises
------
TypeError
If a unicode object is passed
ValueError
If `track=True`, but an untracked Frame is passed.
ZMQError
If the send does not succeed for any reason (including
if NOBLOCK is set and the outgoing queue is full).
.. versionchanged:: 17.0
DRAFT support for routing_id and group arguments.
"""
if routing_id is not None:
if not isinstance(data, zmq.Frame):
data = zmq.Frame(
data,
track=track,
copy=copy or None,
copy_threshold=self.copy_threshold,
)
data.routing_id = routing_id
if group is not None:
if not isinstance(data, zmq.Frame):
data = zmq.Frame(
data,
track=track,
copy=copy or None,
copy_threshold=self.copy_threshold,
)
data.group = group
return super().send(data, flags=flags, copy=copy, track=track)
def send_multipart(
self,
msg_parts: Sequence,
flags: int = 0,
copy: bool = True,
track: bool = False,
**kwargs,
):
"""Send a sequence of buffers as a multipart message.
The zmq.SNDMORE flag is added to all msg parts before the last.
Parameters
----------
msg_parts : iterable
A sequence of objects to send as a multipart message. Each element
can be any sendable object (Frame, bytes, buffer-providers)
flags : int, optional
Any valid flags for :func:`Socket.send`.
SNDMORE is added automatically for frames before the last.
copy : bool, optional
Should the frame(s) be sent in a copying or non-copying manner.
If copy=False, frames smaller than self.copy_threshold bytes
will be copied anyway.
track : bool, optional
Should the frame(s) be tracked for notification that ZMQ has
finished with it (ignored if copy=True).
Returns
-------
None : if copy or not track
MessageTracker : if track and not copy
a MessageTracker object, whose `pending` property will
be True until the last send is completed.
"""
# typecheck parts before sending:
for i, msg in enumerate(msg_parts):
if isinstance(msg, (zmq.Frame, bytes, memoryview)):
continue
try:
memoryview(msg)
except Exception:
rmsg = repr(msg)
if len(rmsg) > 32:
rmsg = rmsg[:32] + '...'
raise TypeError(
"Frame %i (%s) does not support the buffer interface."
% (
i,
rmsg,
)
)
for msg in msg_parts[:-1]:
self.send(msg, zmq.SNDMORE | flags, copy=copy, track=track)
# Send the last part without the extra SNDMORE flag.
return self.send(msg_parts[-1], flags, copy=copy, track=track)
@overload
def recv_multipart(
self, flags: int = ..., *, copy: Literal[True], track: bool = ...
) -> List[bytes]:
...
@overload
def recv_multipart(
self, flags: int = ..., *, copy: Literal[False], track: bool = ...
) -> List[zmq.Frame]:
...
@overload
def recv_multipart(self, flags: int = ..., *, track: bool = ...) -> List[bytes]:
...
@overload
def recv_multipart(
self, flags: int = 0, copy: bool = True, track: bool = False
) -> Union[List[zmq.Frame], List[bytes]]:
...
def recv_multipart(
self, flags: int = 0, copy: bool = True, track: bool = False
) -> Union[List[zmq.Frame], List[bytes]]:
"""Receive a multipart message as a list of bytes or Frame objects
Parameters
----------
flags : int, optional
Any valid flags for :func:`Socket.recv`.
copy : bool, optional
Should the message frame(s) be received in a copying or non-copying manner?
If False a Frame object is returned for each part, if True a copy of
the bytes is made for each frame.
track : bool, optional
Should the message frame(s) be tracked for notification that ZMQ has
finished with it? (ignored if copy=True)
Returns
-------
msg_parts : list
A list of frames in the multipart message; either Frames or bytes,
depending on `copy`.
Raises
------
ZMQError
for any of the reasons :func:`~Socket.recv` might fail
"""
parts = [self.recv(flags, copy=copy, track=track)]
# have first part already, only loop while more to receive
while self.getsockopt(zmq.RCVMORE):
part = self.recv(flags, copy=copy, track=track)
parts.append(part)
# cast List[Union] to Union[List]
# how do we get mypy to recognize that return type is invariant on `copy`?
return cast(Union[List[zmq.Frame], List[bytes]], parts)
def _deserialize(
self,
recvd: bytes,
load: Callable[[bytes], Any],
) -> Any:
"""Deserialize a received message
Override in subclass (e.g. Futures) if recvd is not the raw bytes.
The default implementation expects bytes and returns the deserialized message immediately.
Parameters
----------
load: callable
Callable that deserializes bytes
recvd:
The object returned by self.recv
"""
return load(recvd)
def send_serialized(self, msg, serialize, flags=0, copy=True, **kwargs):
"""Send a message with a custom serialization function.
.. versionadded:: 17
Parameters
----------
msg : The message to be sent. Can be any object serializable by `serialize`.
serialize : callable
The serialization function to use.
serialize(msg) should return an iterable of sendable message frames
(e.g. bytes objects), which will be passed to send_multipart.
flags : int, optional
Any valid flags for :func:`Socket.send`.
copy : bool, optional
Whether to copy the frames.
"""
frames = serialize(msg)
return self.send_multipart(frames, flags=flags, copy=copy, **kwargs)
def recv_serialized(self, deserialize, flags=0, copy=True):
"""Receive a message with a custom deserialization function.
.. versionadded:: 17
Parameters
----------
deserialize : callable
The deserialization function to use.
deserialize will be called with one argument: the list of frames
returned by recv_multipart() and can return any object.
flags : int, optional
Any valid flags for :func:`Socket.recv`.
copy : bool, optional
Whether to recv bytes or Frame objects.
Returns
-------
obj : object
The object returned by the deserialization function.
Raises
------
ZMQError
for any of the reasons :func:`~Socket.recv` might fail
"""
frames = self.recv_multipart(flags=flags, copy=copy)
return self._deserialize(frames, deserialize)
def send_string(
self,
u: str,
flags: int = 0,
copy: bool = True,
encoding: str = 'utf-8',
**kwargs,
) -> Optional["zmq.Frame"]:
"""Send a Python unicode string as a message with an encoding.
0MQ communicates with raw bytes, so you must encode/decode
text (str) around 0MQ.
Parameters
----------
u : str
The unicode string to send.
flags : int, optional
Any valid flags for :func:`Socket.send`.
encoding : str [default: 'utf-8']
The encoding to be used
"""
if not isinstance(u, str):
raise TypeError("str objects only")
return self.send(u.encode(encoding), flags=flags, copy=copy, **kwargs)
send_unicode = send_string
def recv_string(self, flags: int = 0, encoding: str = 'utf-8') -> str:
"""Receive a unicode string, as sent by send_string.
Parameters
----------
flags : int
Any valid flags for :func:`Socket.recv`.
encoding : str [default: 'utf-8']
The encoding to be used
Returns
-------
s : str
The Python unicode string that arrives as encoded bytes.
Raises
------
ZMQError
for any of the reasons :func:`~Socket.recv` might fail
"""
msg = self.recv(flags=flags)
return self._deserialize(msg, lambda buf: buf.decode(encoding))
recv_unicode = recv_string
def send_pyobj(
self, obj: Any, flags: int = 0, protocol: int = DEFAULT_PROTOCOL, **kwargs
) -> Optional[zmq.Frame]:
"""Send a Python object as a message using pickle to serialize.
Parameters
----------
obj : Python object
The Python object to send.
flags : int
Any valid flags for :func:`Socket.send`.
protocol : int
The pickle protocol number to use. The default is pickle.DEFAULT_PROTOCOL
where defined, and pickle.HIGHEST_PROTOCOL elsewhere.
"""
msg = pickle.dumps(obj, protocol)
return self.send(msg, flags=flags, **kwargs)
def recv_pyobj(self, flags: int = 0) -> Any:
"""Receive a Python object as a message using pickle to serialize.
Parameters
----------
flags : int
Any valid flags for :func:`Socket.recv`.
Returns
-------
obj : Python object
The Python object that arrives as a message.
Raises
------
ZMQError
for any of the reasons :func:`~Socket.recv` might fail
"""
msg = self.recv(flags)
return self._deserialize(msg, pickle.loads)
def send_json(self, obj: Any, flags: int = 0, **kwargs) -> None:
"""Send a Python object as a message using json to serialize.
Keyword arguments are passed on to json.dumps
Parameters
----------
obj : Python object
The Python object to send
flags : int
Any valid flags for :func:`Socket.send`
"""
send_kwargs = {}
for key in ('routing_id', 'group'):
if key in kwargs:
send_kwargs[key] = kwargs.pop(key)
msg = jsonapi.dumps(obj, **kwargs)
return self.send(msg, flags=flags, **send_kwargs)
def recv_json(self, flags: int = 0, **kwargs) -> Union[List, str, int, float, Dict]:
"""Receive a Python object as a message using json to serialize.
Keyword arguments are passed on to json.loads
Parameters
----------
flags : int
Any valid flags for :func:`Socket.recv`.
Returns
-------
obj : Python object
The Python object that arrives as a message.
Raises
------
ZMQError
for any of the reasons :func:`~Socket.recv` might fail
"""
msg = self.recv(flags)
return self._deserialize(msg, lambda buf: jsonapi.loads(buf, **kwargs))
_poller_class = Poller
def poll(self, timeout=None, flags=zmq.POLLIN) -> int:
"""Poll the socket for events.
See :class:`Poller` to wait for multiple sockets at once.
Parameters
----------
timeout : int [default: None]
The timeout (in milliseconds) to wait for an event. If unspecified
(or specified None), will wait forever for an event.
flags : int [default: POLLIN]
POLLIN, POLLOUT, or POLLIN|POLLOUT. The event flags to poll for.
Returns
-------
event_mask : int
The poll event mask (POLLIN, POLLOUT),
0 if the timeout was reached without an event.
"""
if self.closed:
raise ZMQError(zmq.ENOTSUP)
p = self._poller_class()
p.register(self, flags)
evts = dict(p.poll(timeout))
# return 0 if no events, otherwise return event bitfield
return evts.get(self, 0)
def get_monitor_socket(
self: T, events: Optional[int] = None, addr: Optional[str] = None
) -> T:
"""Return a connected PAIR socket ready to receive the event notifications.
.. versionadded:: libzmq-4.0
.. versionadded:: 14.0
Parameters
----------
events : int [default: ZMQ_EVENT_ALL]
The bitmask defining which events are wanted.
addr : string [default: None]
The optional endpoint for the monitoring sockets.
Returns
-------
socket : (PAIR)
The socket is already connected and ready to receive messages.
"""
# safe-guard, method only available on libzmq >= 4
if zmq.zmq_version_info() < (4,):
raise NotImplementedError(
"get_monitor_socket requires libzmq >= 4, have %s" % zmq.zmq_version()
)
# if already monitoring, return existing socket
if self._monitor_socket:
if self._monitor_socket.closed:
self._monitor_socket = None
else:
return self._monitor_socket
if addr is None:
# create endpoint name from internal fd
addr = f"inproc://monitor.s-{self.FD}"
if events is None:
# use all events
events = zmq.EVENT_ALL
# attach monitoring socket
self.monitor(addr, events)
# create new PAIR socket and connect it
self._monitor_socket = self.context.socket(zmq.PAIR)
self._monitor_socket.connect(addr)
return self._monitor_socket
def disable_monitor(self) -> None:
"""Shutdown the PAIR socket (created using get_monitor_socket)
that is serving socket events.
.. versionadded:: 14.4
"""
self._monitor_socket = None
self.monitor(None, 0)
__all__ = ['Socket']