zmq#

Python bindings for 0MQ.

Basic Classes#

Context#

class zmq.Context(io_threads: int = 1)#
class zmq.Context(io_threads: Context)
class zmq.Context(*, shadow: Union[Context, int])

Create a zmq Context

A zmq Context creates sockets via its ctx.socket method.

Changed in version 24: When using a Context as a context manager (with zmq.Context()), or deleting a context without closing it first, ctx.destroy() is called, closing any leftover sockets, instead of ctx.term() which requires sockets to be closed first.

This prevents hangs caused by ctx.term() if sockets are left open, but means that unclean destruction of contexts (with sockets left open) is not safe if sockets are managed in other threads.

New in version 25: Contexts can now be shadowed by passing another Context. This helps in creating an async copy of a sync context or vice versa:

ctx = zmq.Context(async_ctx)

Which previously had to be:

ctx = zmq.Context.shadow(async_ctx.underlying)
closed#

boolean - whether the context has been terminated. If True, you can no longer use this Context.

destroy(linger: Optional[int] = None) None#

Close all sockets associated with this context and then terminate the context.

Warning

destroy involves calling zmq_close(), which is NOT threadsafe. If there are active sockets in other threads, this must not be called.

Parameters

linger (int, optional) – If specified, set LINGER on sockets prior to closing them.

get(option)#

Get the value of a context option.

See the 0MQ API documentation for zmq_ctx_get for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Parameters

option (int) –

The option to get. Available values will depend on your version of libzmq. Examples include:

zmq.IO_THREADS, zmq.MAX_SOCKETS

Returns

optval – The value of the option as an integer.

Return type

int

getsockopt(opt: int) Union[str, bytes, int]#

get default socket options for new sockets created by this Context

New in version 13.0.

classmethod instance(io_threads: int = 1) zmq.sugar.context.T#

Returns a global Context instance.

Most single-threaded applications have a single, global Context. Use this method instead of passing around Context instances throughout your code.

A common pattern for classes that depend on Contexts is to use a default argument to enable programs with multiple Contexts but not require the argument for simpler applications:

class MyClass(object):
    def __init__(self, context=None):
        self.context = context or Context.instance()

Changed in version 18.1: When called in a subprocess after forking, a new global instance is created instead of inheriting a Context that won’t work from the parent process.

set(option, optval)#

Set a context option.

See the 0MQ API documentation for zmq_ctx_set for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Parameters
  • option (int) –

    The option to set. Available values will depend on your version of libzmq. Examples include:

    zmq.IO_THREADS, zmq.MAX_SOCKETS
    

  • optval (int) – The value of the option to set.

setsockopt(opt: int, value: Any) None#

set default socket options for new sockets created by this Context

New in version 13.0.

classmethod shadow(address: Union[int, zmq.sugar.context.Context]) zmq.sugar.context.T#

Shadow an existing libzmq context

address is a zmq.Context or an integer (or FFI pointer) representing the address of the libzmq context.

New in version 14.1.

New in version 25: Support for shadowing zmq.Context objects, instead of just integer addresses.

classmethod shadow_pyczmq(ctx: Any) zmq.sugar.context.T#

Shadow an existing pyczmq context

ctx is the FFI zctx_t * pointer

New in version 14.1.

socket(socket_type: int, socket_class: Optional[Callable[[zmq.sugar.context.T, int], zmq.sugar.context.ST]] = None, **kwargs: Any) zmq.sugar.context.ST#

Create a Socket associated with this Context.

Parameters
  • socket_type (int) – The socket type, which can be any of the 0MQ socket types: REQ, REP, PUB, SUB, PAIR, DEALER, ROUTER, PULL, PUSH, etc.

  • socket_class (zmq.Socket or a subclass) –

    The socket class to instantiate, if different from the default for this Context. e.g. for creating an asyncio socket attached to a default Context or vice versa.

    New in version 25.

  • kwargs – will be passed to the __init__ method of the socket class.

term() None#

Close or terminate the context.

Context termination is performed in the following steps:

  • Any blocking operations currently in progress on sockets open within context shall raise zmq.ContextTerminated. With the exception of socket.close(), any further operations on sockets open within this context shall raise zmq.ContextTerminated.

  • After interrupting all blocking calls, term shall block until the following conditions are satisfied:
    • All sockets open within context have been closed.

    • For each socket within context, all messages sent on the socket have either been physically transferred to a network peer, or the socket’s linger period set with the zmq.LINGER socket option has expired.

For further details regarding socket linger behaviour refer to libzmq documentation for ZMQ_LINGER.

This can be called to close the context by hand. If this is not called, the context will automatically be closed when it is garbage collected.

underlying#

The address of the underlying libzmq context

Socket#

class zmq.Socket(ctx_or_socket: zmq.Context, socket_type: int, *, copy_threshold: Optional[int] = 'None')#
class zmq.Socket(*, shadow: Union[Socket, int], copy_threshold: Optional[int] = 'None')
class zmq.Socket(ctx_or_socket: Socket)

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)

New in version 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)
closed#

boolean - whether the socket has been closed. If True, you can no longer use this Socket.

copy_threshold#

integer - size (in bytes) below which messages should always be copied. Zero-copy support has nontrivial overhead due to the need to coordinate garbage collection with the libzmq IO thread, so sending small messages (typically < 10s of kB) with copy=False is often more expensive than with copy=True. The initial default value is 65536 (64kB), a reasonable default based on testing.

Defaults to zmq.COPY_THRESHOLD on socket construction. Setting zmq.COPY_THRESHOLD will define the default value for any subsequently created sockets.

New in version 17.

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.

New in version 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.

bind_to_random_port(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 – The port the socket was bound to.

Return type

int

Raises

ZMQBindError – if max_tries reached before successful bind

close(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.

connect(addr)#

Connect to a remote 0MQ socket.

Returns a context manager which will call disconnect on exit.

New in version 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.

disable_monitor() None#

Shutdown the PAIR socket (created using get_monitor_socket) that is serving socket events.

New in version 14.4.

disconnect(addr)#

Disconnect from a remote 0MQ socket (undoes a call to connect).

New in version libzmq-3.2.

New in version 13.0.

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.

fileno() 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.

New in version 17.0.

get(option)#

Get the value of a socket option.

See the 0MQ API documentation for details on specific options.

Parameters

option (int) –

The option to get. Available values will depend on your version of libzmq. Examples include:

zmq.IDENTITY, HWM, LINGER, FD, EVENTS

Returns

optval – The value of the option as a bytestring or int.

Return type

int or bytes

get_hwm() int#

Get the High Water Mark.

On libzmq ≥ 3, this gets SNDHWM if available, otherwise RCVHWM

get_monitor_socket(events: Optional[int] = None, addr: Optional[str] = None) zmq.sugar.socket.T#

Return a connected PAIR socket ready to receive the event notifications.

New in version libzmq-4.0.

New in version 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 – The socket is already connected and ready to receive messages.

Return type

(PAIR)

get_string(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 – The value of the option as a unicode string.

Return type

str

getsockopt(option)#

s.get(option)

Get the value of a socket option.

See the 0MQ API documentation for details on specific options.

Parameters

option (int) –

The option to get. Available values will depend on your version of libzmq. Examples include:

zmq.IDENTITY, HWM, LINGER, FD, EVENTS

Returns

optval – The value of the option as a bytestring or int.

Return type

int or bytes

getsockopt_string(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 – The value of the option as a unicode string.

Return type

str

property hwm: int#

Property for High Water Mark.

Setting hwm sets both SNDHWM and RCVHWM as appropriate. It gets SNDHWM if available, otherwise RCVHWM.

join(group)#

Join a RADIO-DISH group

Only for DISH sockets.

libzmq and pyzmq must have been built with ZMQ_BUILD_DRAFT_API

New in version 17.

leave(group)#

Leave a RADIO-DISH group

Only for DISH sockets.

libzmq and pyzmq must have been built with ZMQ_BUILD_DRAFT_API

New in version 17.

monitor(addr, flags)#

Start publishing socket events on inproc. See libzmq docs for zmq_monitor for details.

While this function is available from libzmq 3.2, pyzmq cannot parse monitor messages from libzmq prior to 4.0.

Parameters
  • addr (str) – The inproc url used for monitoring. Passing None as the addr will cause an existing socket monitor to be deregistered.

  • events (int [default: zmq.EVENT_ALL]) – The zmq event bitmask for which events will be sent to the monitor.

poll(timeout=None, flags=PollEvent.POLLIN) int#

Poll the socket for events. See 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 – The poll event mask (POLLIN, POLLOUT), 0 if the timeout was reached without an event.

Return type

int

recv(flags=0, copy=True, track=False)#

Receive a message.

With flags=NOBLOCK, this raises ZMQError if no messages have arrived; otherwise, this waits until a message arrives. See Poller for more general non-blocking I/O.

Parameters
  • flags (int) – 0 or NOBLOCK.

  • copy (bool) – Should the message be received in a copying or non-copying manner? If False a Frame object is returned, if True a string copy of message is returned.

  • track (bool) – Should the message be tracked for notification that ZMQ has finished with it? (ignored if copy=True)

Returns

msg – The received message frame. If copy is False, then it will be a Frame, otherwise it will be bytes.

Return type

bytes or Frame

Raises

ZMQError – for any of the reasons zmq_msg_recv might fail (including if NOBLOCK is set and no new messages have arrived).

recv_json(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 Socket.recv().

Returns

obj – The Python object that arrives as a message.

Return type

Python object

Raises

ZMQError – for any of the reasons recv() might fail

recv_multipart(flags: int = 0, *, copy: typing_extensions.Literal[True], track: bool = False) List[bytes]#
recv_multipart(flags: int = 0, *, copy: typing_extensions.Literal[False], track: bool = False) List[zmq.sugar.frame.Frame]
recv_multipart(flags: int = 0, *, track: bool = False) List[bytes]
recv_multipart(flags: int = 0, copy: bool = True, track: bool = False) Union[List[zmq.sugar.frame.Frame], List[bytes]]

Receive a multipart message as a list of bytes or Frame objects

Parameters
  • flags (int, optional) – Any valid flags for 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 – A list of frames in the multipart message; either Frames or bytes, depending on copy.

Return type

list

Raises

ZMQError – for any of the reasons recv() might fail

recv_pyobj(flags: int = 0) Any#

Receive a Python object as a message using pickle to serialize.

Parameters

flags (int) – Any valid flags for Socket.recv().

Returns

obj – The Python object that arrives as a message.

Return type

Python object

Raises

ZMQError – for any of the reasons recv() might fail

recv_serialized(deserialize, flags=0, copy=True)#

Receive a message with a custom deserialization function.

New in version 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 Socket.recv().

  • copy (bool, optional) – Whether to recv bytes or Frame objects.

Returns

obj – The object returned by the deserialization function.

Return type

object

Raises

ZMQError – for any of the reasons recv() might fail

recv_string(flags: int = 0, encoding: str = 'utf-8') str#

Receive a unicode string, as sent by send_string.

Parameters
  • flags (int) – Any valid flags for Socket.recv().

  • encoding (str [default: 'utf-8']) – The encoding to be used

Returns

s – The Python unicode string that arrives as encoded bytes.

Return type

str

Raises

ZMQError – for any of the reasons recv() might fail

send(data: Any, flags: int = 0, copy: bool = True, *, track: typing_extensions.Literal[True], routing_id: Optional[int] = None, group: Optional[str] = None) zmq.MessageTracker#
send(data: Any, flags: int = 0, copy: bool = True, *, track: typing_extensions.Literal[False], routing_id: Optional[int] = None, group: Optional[str] = None) None
send(data: Any, flags: int = 0, *, copy: bool = True, routing_id: Optional[int] = None, group: Optional[str] = None) None
send(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 ZMQError if the queue is full; otherwise, this waits until space is available. See 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).

Changed in version 17.0: DRAFT support for routing_id and group arguments.

send_json(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 Socket.send()

send_multipart(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 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.

send_pyobj(obj: Any, flags: int = 0, protocol: int = 3, **kwargs) Optional[zmq.backend.cython.message.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 Socket.send().

  • protocol (int) – The pickle protocol number to use. The default is pickle.DEFAULT_PROTOCOL where defined, and pickle.HIGHEST_PROTOCOL elsewhere.

send_serialized(msg, serialize, flags=0, copy=True, **kwargs)#

Send a message with a custom serialization function.

New in version 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 Socket.send().

  • copy (bool, optional) – Whether to copy the frames.

send_string(u: str, flags: int = 0, copy: bool = True, encoding: str = 'utf-8', **kwargs) Optional[zmq.sugar.frame.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 Socket.send().

  • encoding (str [default: 'utf-8']) – The encoding to be used

set(option, optval)#

Set socket options.

See the 0MQ API documentation for details on specific options.

Parameters
  • option (int) –

    The option to set. Available values will depend on your version of libzmq. Examples include:

    zmq.SUBSCRIBE, UNSUBSCRIBE, IDENTITY, HWM, LINGER, FD
    

  • optval (int or bytes) – The value of the option to set.

Notes

Warning

All options other than zmq.SUBSCRIBE, zmq.UNSUBSCRIBE and zmq.LINGER only take effect for subsequent socket bind/connects.

set_hwm(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.

set_string(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

setsockopt(option, optval)#

s.set(option, optval)

Set socket options.

See the 0MQ API documentation for details on specific options.

Parameters
  • option (int) –

    The option to set. Available values will depend on your version of libzmq. Examples include:

    zmq.SUBSCRIBE, UNSUBSCRIBE, IDENTITY, HWM, LINGER, FD
    

  • optval (int or bytes) – The value of the option to set.

Notes

Warning

All options other than zmq.SUBSCRIBE, zmq.UNSUBSCRIBE and zmq.LINGER only take effect for subsequent socket bind/connects.

setsockopt_string(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

classmethod shadow(address: Union[int, zmq.sugar.socket.Socket]) zmq.sugar.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.

New in version 14.1.

New in version 25: Support for shadowing zmq.Socket objects, instead of just integer addresses.

subscribe(topic: Union[str, bytes]) None#

Subscribe to a topic

Only for SUB sockets.

New in version 15.3.

unbind(addr)#

Unbind from an address (undoes a call to bind).

New in version libzmq-3.2.

New in version 13.0.

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.

underlying#

The address of the underlying libzmq socket

unsubscribe(topic: Union[str, bytes]) None#

Unsubscribe from a topic

Only for SUB sockets.

New in version 15.3.

Frame#

class zmq.Frame(data=None, track=False, copy=None, copy_threshold=zmq.COPY_THRESHOLD)#

A zmq message Frame class for non-copying send/recvs and access to message properties.

A zmq.Frame wraps an underlying zmq_msg_t.

Message properties can be accessed by treating a Frame like a dictionary (frame["User-Id"]).

New in version 14.4,: libzmq 4

Frames created by recv(copy=False) can be used to access message properties and attributes, such as the CURVE User-Id.

For example:

frames = socket.recv_multipart(copy=False)
user_id = frames[0]["User-Id"]

This class is used if you want to do non-copying send and recvs. When you pass a chunk of bytes to this class, e.g. Frame(buf), the ref-count of buf is increased by two: once because the Frame saves buf as an instance attribute and another because a ZMQ message is created that points to the buffer of buf. This second ref-count increase makes sure that buf lives until all messages that use it have been sent. Once 0MQ sends all the messages and it doesn’t need the buffer of buf, 0MQ will call Py_DECREF(s).

Parameters
  • data (object, optional) – any object that provides the buffer interface will be used to construct the 0MQ message data.

  • track (bool [default: False]) – whether a MessageTracker should be created to track this object. Tracking a message has a cost at creation, because it creates a threadsafe Event object.

  • copy (bool [default: use copy_threshold]) – Whether to create a copy of the data to pass to libzmq or share the memory with libzmq. If unspecified, copy_threshold is used.

  • copy_threshold (int [default: zmq.COPY_THRESHOLD]) – If copy is unspecified, messages smaller than this many bytes will be copied and messages larger than this will be shared with libzmq.

buffer#

A memoryview of the message contents.

bytes#

The message content as a Python bytes object.

The first time this property is accessed, a copy of the message contents is made. From then on that same copy of the message is returned.

get(option)#

Get a Frame option or property.

See the 0MQ API documentation for zmq_msg_get and zmq_msg_gets for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Changed in version 14.3: add support for zmq_msg_gets (requires libzmq-4.1) All message properties are strings.

Changed in version 17.0: Added support for routing_id and group. Only available if draft API is enabled with libzmq >= 4.2.

property group#

The RADIO-DISH group of the message.

Requires libzmq >= 4.2 and pyzmq built with draft APIs enabled.

New in version 17.

property routing_id#

The CLIENT-SERVER routing id of the message.

Requires libzmq >= 4.2 and pyzmq built with draft APIs enabled.

New in version 17.

set(option, value)#

Set a Frame option.

See the 0MQ API documentation for zmq_msg_set for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Changed in version 17.0: Added support for routing_id and group. Only available if draft API is enabled with libzmq >= 4.2.

MessageTracker#

class zmq.MessageTracker(*towatch)#

A class for tracking if 0MQ is done using one or more messages.

When you send a 0MQ message, it is not sent immediately. The 0MQ IO thread sends the message at some later time. Often you want to know when 0MQ has actually sent the message though. This is complicated by the fact that a single 0MQ message can be sent multiple times using different sockets. This class allows you to track all of the 0MQ usages of a message.

Parameters

towatch (Event, MessageTracker, Message instances.) – This objects to track. This class can track the low-level Events used by the Message class, other MessageTrackers or actual Messages.

property done#

Is 0MQ completely done with the message(s) being tracked?

wait(timeout=- 1)#

Wait for 0MQ to be done with the message or until timeout.

Parameters

timeout (float [default: -1, wait forever]) – Maximum time in (s) to wait before raising NotDone.

Returns

if done before timeout

Return type

None

Raises

NotDone – if timeout reached before I am done.

Polling#

Poller#

class zmq.Poller#

A stateful poll interface that mirrors Python’s built-in poll.

modify(socket, flags=PollEvent.None)#

Modify the flags for an already registered 0MQ socket or native fd.

poll(timeout: Optional[int] = None) List[Tuple[Any, int]]#

Poll the registered 0MQ or native fds for I/O.

If there are currently events ready to be processed, this function will return immediately. Otherwise, this function will return as soon the first event is available or after timeout milliseconds have elapsed.

Parameters

timeout (int) – The timeout in milliseconds. If None, no timeout (infinite). This is in milliseconds to be compatible with select.poll().

Returns

events – The list of events that are ready to be processed. This is a list of tuples of the form (socket, event_mask), where the 0MQ Socket or integer fd is the first element, and the poll event mask (POLLIN, POLLOUT) is the second. It is common to call events = dict(poller.poll()), which turns the list of tuples into a mapping of socket : event_mask.

Return type

list of tuples

register(socket, flags=POLLIN | POLLOUT)#

Register a 0MQ socket or native fd for I/O monitoring.

register(s,0) is equivalent to unregister(s).

Parameters
  • socket (zmq.Socket or native socket) – A zmq.Socket or any Python object having a fileno() method that returns a valid file descriptor.

  • flags (int) – The events to watch for. Can be POLLIN, POLLOUT or POLLIN|POLLOUT. If flags=0, socket will be unregistered.

unregister(socket: Any)#

Remove a 0MQ socket or native fd for I/O monitoring.

Parameters

socket (Socket) – The socket instance to stop polling.

zmq.select(rlist, wlist, xlist, timeout=None)#

Return the result of poll as a lists of sockets ready for r/w/exception.

This has the same interface as Python’s built-in select.select() function.

Parameters
  • timeout (float, int, optional) – The timeout in seconds. If None, no timeout (infinite). This is in seconds to be compatible with select.select().

  • rlist (list of sockets/FDs) – sockets/FDs to be polled for read events

  • wlist (list of sockets/FDs) – sockets/FDs to be polled for write events

  • xlist (list of sockets/FDs) – sockets/FDs to be polled for error events

Returns

(rlist, wlist, xlist) – Lists correspond to sockets available for read/write/error events respectively.

Return type

tuple of lists of sockets (length 3)

Constants#

All libzmq constants are available as top-level attributes (zmq.PUSH, etc.), as well as via enums (zmq.SocketType.PUSH, etc.).

Changed in version 23: constants for unavailable socket types or draft features will always be defined in pyzmq, whether the features themselves are available or not.

New in version 23: Each category of zmq constant is now available as an IntEnum.

enum zmq.SocketType(value)#

zmq socket types

New in version 23.

Member Type

int

Valid values are as follows:

PAIR = <SocketType.PAIR: 0>#
PUB = <SocketType.PUB: 1>#
SUB = <SocketType.SUB: 2>#
REQ = <SocketType.REQ: 3>#
REP = <SocketType.REP: 4>#
DEALER = <SocketType.DEALER: 5>#
ROUTER = <SocketType.ROUTER: 6>#
PULL = <SocketType.PULL: 7>#
PUSH = <SocketType.PUSH: 8>#
XPUB = <SocketType.XPUB: 9>#
XSUB = <SocketType.XSUB: 10>#
STREAM = <SocketType.STREAM: 11>#
SERVER = <SocketType.SERVER: 12>#
CLIENT = <SocketType.CLIENT: 13>#
RADIO = <SocketType.RADIO: 14>#
DISH = <SocketType.DISH: 15>#
GATHER = <SocketType.GATHER: 16>#
SCATTER = <SocketType.SCATTER: 17>#
DGRAM = <SocketType.DGRAM: 18>#
PEER = <SocketType.PEER: 19>#
CHANNEL = <SocketType.CHANNEL: 20>#
enum zmq.SocketOption(value)#

Options for Socket.get/set

New in version 23.

Member Type

int

Valid values are as follows:

HWM = <SocketOption.HWM: 1>#
AFFINITY = <SocketOption.AFFINITY: 4>#
ROUTING_ID = <SocketOption.ROUTING_ID: 5>#
SUBSCRIBE = <SocketOption.SUBSCRIBE: 6>#
UNSUBSCRIBE = <SocketOption.UNSUBSCRIBE: 7>#
RATE = <SocketOption.RATE: 8>#
RECOVERY_IVL = <SocketOption.RECOVERY_IVL: 9>#
SNDBUF = <SocketOption.SNDBUF: 11>#
RCVBUF = <SocketOption.RCVBUF: 12>#
RCVMORE = <SocketOption.RCVMORE: 13>#
FD = <SocketOption.FD: 14>#
EVENTS = <SocketOption.EVENTS: 15>#
TYPE = <SocketOption.TYPE: 16>#
LINGER = <SocketOption.LINGER: 17>#
RECONNECT_IVL = <SocketOption.RECONNECT_IVL: 18>#
BACKLOG = <SocketOption.BACKLOG: 19>#
RECONNECT_IVL_MAX = <SocketOption.RECONNECT_IVL_MAX: 21>#
MAXMSGSIZE = <SocketOption.MAXMSGSIZE: 22>#
SNDHWM = <SocketOption.SNDHWM: 23>#
RCVHWM = <SocketOption.RCVHWM: 24>#
MULTICAST_HOPS = <SocketOption.MULTICAST_HOPS: 25>#
RCVTIMEO = <SocketOption.RCVTIMEO: 27>#
SNDTIMEO = <SocketOption.SNDTIMEO: 28>#
LAST_ENDPOINT = <SocketOption.LAST_ENDPOINT: 32>#
ROUTER_MANDATORY = <SocketOption.ROUTER_MANDATORY: 33>#
TCP_KEEPALIVE = <SocketOption.TCP_KEEPALIVE: 34>#
TCP_KEEPALIVE_CNT = <SocketOption.TCP_KEEPALIVE_CNT: 35>#
TCP_KEEPALIVE_IDLE = <SocketOption.TCP_KEEPALIVE_IDLE: 36>#
TCP_KEEPALIVE_INTVL = <SocketOption.TCP_KEEPALIVE_INTVL: 37>#
IMMEDIATE = <SocketOption.IMMEDIATE: 39>#
XPUB_VERBOSE = <SocketOption.XPUB_VERBOSE: 40>#
ROUTER_RAW = <SocketOption.ROUTER_RAW: 41>#
IPV6 = <SocketOption.IPV6: 42>#
MECHANISM = <SocketOption.MECHANISM: 43>#
PLAIN_SERVER = <SocketOption.PLAIN_SERVER: 44>#
PLAIN_USERNAME = <SocketOption.PLAIN_USERNAME: 45>#
PLAIN_PASSWORD = <SocketOption.PLAIN_PASSWORD: 46>#
CURVE_SERVER = <SocketOption.CURVE_SERVER: 47>#
CURVE_PUBLICKEY = <SocketOption.CURVE_PUBLICKEY: 48>#
CURVE_SECRETKEY = <SocketOption.CURVE_SECRETKEY: 49>#
CURVE_SERVERKEY = <SocketOption.CURVE_SERVERKEY: 50>#
PROBE_ROUTER = <SocketOption.PROBE_ROUTER: 51>#
REQ_CORRELATE = <SocketOption.REQ_CORRELATE: 52>#
REQ_RELAXED = <SocketOption.REQ_RELAXED: 53>#
CONFLATE = <SocketOption.CONFLATE: 54>#
ZAP_DOMAIN = <SocketOption.ZAP_DOMAIN: 55>#
ROUTER_HANDOVER = <SocketOption.ROUTER_HANDOVER: 56>#
TOS = <SocketOption.TOS: 57>#
CONNECT_ROUTING_ID = <SocketOption.CONNECT_ROUTING_ID: 61>#
GSSAPI_SERVER = <SocketOption.GSSAPI_SERVER: 62>#
GSSAPI_PRINCIPAL = <SocketOption.GSSAPI_PRINCIPAL: 63>#
GSSAPI_SERVICE_PRINCIPAL = <SocketOption.GSSAPI_SERVICE_PRINCIPAL: 64>#
GSSAPI_PLAINTEXT = <SocketOption.GSSAPI_PLAINTEXT: 65>#
HANDSHAKE_IVL = <SocketOption.HANDSHAKE_IVL: 66>#
SOCKS_PROXY = <SocketOption.SOCKS_PROXY: 68>#
XPUB_NODROP = <SocketOption.XPUB_NODROP: 69>#
BLOCKY = <SocketOption.BLOCKY: 70>#
XPUB_MANUAL = <SocketOption.XPUB_MANUAL: 71>#
XPUB_WELCOME_MSG = <SocketOption.XPUB_WELCOME_MSG: 72>#
STREAM_NOTIFY = <SocketOption.STREAM_NOTIFY: 73>#
INVERT_MATCHING = <SocketOption.INVERT_MATCHING: 74>#
HEARTBEAT_IVL = <SocketOption.HEARTBEAT_IVL: 75>#
HEARTBEAT_TTL = <SocketOption.HEARTBEAT_TTL: 76>#
HEARTBEAT_TIMEOUT = <SocketOption.HEARTBEAT_TIMEOUT: 77>#
XPUB_VERBOSER = <SocketOption.XPUB_VERBOSER: 78>#
CONNECT_TIMEOUT = <SocketOption.CONNECT_TIMEOUT: 79>#
TCP_MAXRT = <SocketOption.TCP_MAXRT: 80>#
THREAD_SAFE = <SocketOption.THREAD_SAFE: 81>#
MULTICAST_MAXTPDU = <SocketOption.MULTICAST_MAXTPDU: 84>#
VMCI_BUFFER_SIZE = <SocketOption.VMCI_BUFFER_SIZE: 85>#
VMCI_BUFFER_MIN_SIZE = <SocketOption.VMCI_BUFFER_MIN_SIZE: 86>#
VMCI_BUFFER_MAX_SIZE = <SocketOption.VMCI_BUFFER_MAX_SIZE: 87>#
VMCI_CONNECT_TIMEOUT = <SocketOption.VMCI_CONNECT_TIMEOUT: 88>#
USE_FD = <SocketOption.USE_FD: 89>#
GSSAPI_PRINCIPAL_NAMETYPE = <SocketOption.GSSAPI_PRINCIPAL_NAMETYPE: 90>#
GSSAPI_SERVICE_PRINCIPAL_NAMETYPE = <SocketOption.GSSAPI_SERVICE_PRINCIPAL_NAMETYPE: 91>#
BINDTODEVICE = <SocketOption.BINDTODEVICE: 92>#
TCP_ACCEPT_FILTER = <SocketOption.TCP_ACCEPT_FILTER: 38>#
IPC_FILTER_PID = <SocketOption.IPC_FILTER_PID: 58>#
IPC_FILTER_UID = <SocketOption.IPC_FILTER_UID: 59>#
IPC_FILTER_GID = <SocketOption.IPC_FILTER_GID: 60>#
IPV4ONLY = <SocketOption.IPV4ONLY: 31>#
ZAP_ENFORCE_DOMAIN = <SocketOption.ZAP_ENFORCE_DOMAIN: 93>#
LOOPBACK_FASTPATH = <SocketOption.LOOPBACK_FASTPATH: 94>#
METADATA = <SocketOption.METADATA: 95>#
MULTICAST_LOOP = <SocketOption.MULTICAST_LOOP: 96>#
ROUTER_NOTIFY = <SocketOption.ROUTER_NOTIFY: 97>#
XPUB_MANUAL_LAST_VALUE = <SocketOption.XPUB_MANUAL_LAST_VALUE: 98>#
SOCKS_USERNAME = <SocketOption.SOCKS_USERNAME: 99>#
SOCKS_PASSWORD = <SocketOption.SOCKS_PASSWORD: 100>#
IN_BATCH_SIZE = <SocketOption.IN_BATCH_SIZE: 101>#
OUT_BATCH_SIZE = <SocketOption.OUT_BATCH_SIZE: 102>#
WSS_KEY_PEM = <SocketOption.WSS_KEY_PEM: 103>#
WSS_CERT_PEM = <SocketOption.WSS_CERT_PEM: 104>#
WSS_TRUST_PEM = <SocketOption.WSS_TRUST_PEM: 105>#
WSS_HOSTNAME = <SocketOption.WSS_HOSTNAME: 106>#
WSS_TRUST_SYSTEM = <SocketOption.WSS_TRUST_SYSTEM: 107>#
ONLY_FIRST_SUBSCRIBE = <SocketOption.ONLY_FIRST_SUBSCRIBE: 108>#
RECONNECT_STOP = <SocketOption.RECONNECT_STOP: 109>#
HELLO_MSG = <SocketOption.HELLO_MSG: 110>#
DISCONNECT_MSG = <SocketOption.DISCONNECT_MSG: 111>#
PRIORITY = <SocketOption.PRIORITY: 112>#
enum zmq.Flag(value)#

Send/recv flags

New in version 23.

Member Type

int

Valid values are as follows:

DONTWAIT = <Flag.DONTWAIT: 1>#
SNDMORE = <Flag.SNDMORE: 2>#
enum zmq.PollEvent(value)#

Which events to poll for in poll methods

Member Type

int

Valid values are as follows:

POLLIN = <PollEvent.POLLIN: 1>#
POLLOUT = <PollEvent.POLLOUT: 2>#
POLLERR = <PollEvent.POLLERR: 4>#
POLLPRI = <PollEvent.POLLPRI: 8>#
enum zmq.ContextOption(value)#

Options for Context.get/set

New in version 23.

Member Type

int

Valid values are as follows:

IO_THREADS = <ContextOption.IO_THREADS: 1>#
MAX_SOCKETS = <ContextOption.MAX_SOCKETS: 2>#
SOCKET_LIMIT = <ContextOption.SOCKET_LIMIT: 3>#
THREAD_SCHED_POLICY = <ContextOption.THREAD_SCHED_POLICY: 4>#
MAX_MSGSZ = <ContextOption.MAX_MSGSZ: 5>#
MSG_T_SIZE = <ContextOption.MSG_T_SIZE: 6>#
THREAD_AFFINITY_CPU_ADD = <ContextOption.THREAD_AFFINITY_CPU_ADD: 7>#
THREAD_AFFINITY_CPU_REMOVE = <ContextOption.THREAD_AFFINITY_CPU_REMOVE: 8>#
THREAD_NAME_PREFIX = <ContextOption.THREAD_NAME_PREFIX: 9>#
enum zmq.MessageOption(value)#

Options on zmq.Frame objects

New in version 23.

Member Type

int

Valid values are as follows:

MORE = <MessageOption.MORE: 1>#
SHARED = <MessageOption.SHARED: 3>#
SRCFD = <MessageOption.SRCFD: 2>#
enum zmq.Event(value)#

Socket monitoring events

New in version 23.

Member Type

int

Valid values are as follows:

PROTOCOL_ERROR_WS_UNSPECIFIED = <Event.PROTOCOL_ERROR_WS_UNSPECIFIED: 805306368>#
PROTOCOL_ERROR_ZMTP_UNSPECIFIED = <Event.PROTOCOL_ERROR_ZMTP_UNSPECIFIED: 268435456>#
PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND = <Event.PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND: 268435457>#
PROTOCOL_ERROR_ZMTP_INVALID_SEQUENCE = <Event.PROTOCOL_ERROR_ZMTP_INVALID_SEQUENCE: 268435458>#
PROTOCOL_ERROR_ZMTP_KEY_EXCHANGE = <Event.PROTOCOL_ERROR_ZMTP_KEY_EXCHANGE: 268435459>#
PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_UNSPECIFIED = <Event.PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_UNSPECIFIED: 268435473>#
PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_MESSAGE = <Event.PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_MESSAGE: 268435474>#
PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_HELLO = <Event.PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_HELLO: 268435475>#
PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_INITIATE = <Event.PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_INITIATE: 268435476>#
PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_ERROR = <Event.PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_ERROR: 268435477>#
PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_READY = <Event.PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_READY: 268435478>#
PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_WELCOME = <Event.PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_WELCOME: 268435479>#
PROTOCOL_ERROR_ZMTP_INVALID_METADATA = <Event.PROTOCOL_ERROR_ZMTP_INVALID_METADATA: 268435480>#
PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC = <Event.PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC: 285212673>#
PROTOCOL_ERROR_ZMTP_MECHANISM_MISMATCH = <Event.PROTOCOL_ERROR_ZMTP_MECHANISM_MISMATCH: 285212674>#
PROTOCOL_ERROR_ZAP_UNSPECIFIED = <Event.PROTOCOL_ERROR_ZAP_UNSPECIFIED: 536870912>#
PROTOCOL_ERROR_ZAP_MALFORMED_REPLY = <Event.PROTOCOL_ERROR_ZAP_MALFORMED_REPLY: 536870913>#
PROTOCOL_ERROR_ZAP_BAD_REQUEST_ID = <Event.PROTOCOL_ERROR_ZAP_BAD_REQUEST_ID: 536870914>#
PROTOCOL_ERROR_ZAP_BAD_VERSION = <Event.PROTOCOL_ERROR_ZAP_BAD_VERSION: 536870915>#
PROTOCOL_ERROR_ZAP_INVALID_STATUS_CODE = <Event.PROTOCOL_ERROR_ZAP_INVALID_STATUS_CODE: 536870916>#
PROTOCOL_ERROR_ZAP_INVALID_METADATA = <Event.PROTOCOL_ERROR_ZAP_INVALID_METADATA: 536870917>#
CONNECTED = <Event.CONNECTED: 1>#
CONNECT_DELAYED = <Event.CONNECT_DELAYED: 2>#
CONNECT_RETRIED = <Event.CONNECT_RETRIED: 4>#
LISTENING = <Event.LISTENING: 8>#
BIND_FAILED = <Event.BIND_FAILED: 16>#
ACCEPTED = <Event.ACCEPTED: 32>#
ACCEPT_FAILED = <Event.ACCEPT_FAILED: 64>#
CLOSED = <Event.CLOSED: 128>#
CLOSE_FAILED = <Event.CLOSE_FAILED: 256>#
DISCONNECTED = <Event.DISCONNECTED: 512>#
MONITOR_STOPPED = <Event.MONITOR_STOPPED: 1024>#
HANDSHAKE_FAILED_NO_DETAIL = <Event.HANDSHAKE_FAILED_NO_DETAIL: 2048>#
HANDSHAKE_SUCCEEDED = <Event.HANDSHAKE_SUCCEEDED: 4096>#
HANDSHAKE_FAILED_PROTOCOL = <Event.HANDSHAKE_FAILED_PROTOCOL: 8192>#
HANDSHAKE_FAILED_AUTH = <Event.HANDSHAKE_FAILED_AUTH: 16384>#
ALL_V1 = <Event.ALL_V1: 65535>#
PIPES_STATS = <Event.PIPES_STATS: 65536>#
ALL_V2 = <Event.ALL_V2: 131071>#
enum zmq.SecurityMechanism(value)#

Security mechanisms (as returned by socket.get(zmq.MECHANISM))

New in version 23.

Member Type

int

Valid values are as follows:

NULL = <SecurityMechanism.NULL: 0>#
PLAIN = <SecurityMechanism.PLAIN: 1>#
CURVE = <SecurityMechanism.CURVE: 2>#
GSSAPI = <SecurityMechanism.GSSAPI: 3>#
enum zmq.DeviceType(value)#

Device type constants for zmq.device

Member Type

int

Valid values are as follows:

STREAMER = <DeviceType.STREAMER: 1>#
FORWARDER = <DeviceType.FORWARDER: 2>#
QUEUE = <DeviceType.QUEUE: 3>#
enum zmq.Errno(value)#

libzmq error codes

New in version 23.

Member Type

int

Valid values are as follows:

EAGAIN = <Errno.EAGAIN: 11>#
EFAULT = <Errno.EFAULT: 14>#
EINVAL = <Errno.EINVAL: 22>#
ENOTSUP = <Errno.ENOTSUP: 95>#
EPROTONOSUPPORT = <Errno.EPROTONOSUPPORT: 93>#
ENOBUFS = <Errno.ENOBUFS: 105>#
ENETDOWN = <Errno.ENETDOWN: 100>#
EADDRINUSE = <Errno.EADDRINUSE: 98>#
EADDRNOTAVAIL = <Errno.EADDRNOTAVAIL: 99>#
ECONNREFUSED = <Errno.ECONNREFUSED: 111>#
EINPROGRESS = <Errno.EINPROGRESS: 115>#
ENOTSOCK = <Errno.ENOTSOCK: 88>#
EMSGSIZE = <Errno.EMSGSIZE: 90>#
EAFNOSUPPORT = <Errno.EAFNOSUPPORT: 97>#
ENETUNREACH = <Errno.ENETUNREACH: 101>#
ECONNABORTED = <Errno.ECONNABORTED: 103>#
ECONNRESET = <Errno.ECONNRESET: 104>#
ENOTCONN = <Errno.ENOTCONN: 107>#
ETIMEDOUT = <Errno.ETIMEDOUT: 110>#
EHOSTUNREACH = <Errno.EHOSTUNREACH: 113>#
ENETRESET = <Errno.ENETRESET: 102>#
EFSM = <Errno.EFSM: 156384763>#
ENOCOMPATPROTO = <Errno.ENOCOMPATPROTO: 156384764>#
ETERM = <Errno.ETERM: 156384765>#
EMTHREAD = <Errno.EMTHREAD: 156384766>#

Exceptions#

ZMQError#

class zmq.ZMQError(errno: Optional[int] = None, msg: Optional[str] = None)#

Wrap an errno style error.

Parameters
  • errno (int) – The ZMQ errno or None. If None, then zmq_errno() is called and used.

  • msg (string) – Description of the error or None.

with_traceback()#

Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

ZMQVersionError#

class zmq.ZMQVersionError(min_version: str, msg: str = 'Feature')#

Raised when a feature is not provided by the linked version of libzmq.

New in version 14.2.

with_traceback()#

Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

Again#

class zmq.Again(errno='ignored', msg='ignored')#

Wrapper for zmq.EAGAIN

New in version 13.0.

ContextTerminated#

class zmq.ContextTerminated(errno='ignored', msg='ignored')#

Wrapper for zmq.ETERM

New in version 13.0.

NotDone#

class zmq.NotDone#

Raised when timeout is reached while waiting for 0MQ to finish with a Message

See also

MessageTracker.wait

object for tracking when ZeroMQ is done

ZMQBindError#

class zmq.ZMQBindError#

An error for Socket.bind_to_random_port().

Functions#

zmq.zmq_version() str#

return the version of libzmq as a string

zmq.pyzmq_version() str#

return the version of pyzmq as a string

zmq.zmq_version_info()#

Return the version of ZeroMQ itself as a 3-tuple of ints.

zmq.pyzmq_version_info() Union[Tuple[int, int, int], Tuple[int, int, int, float]]#

return the pyzmq version as a tuple of at least three numbers

If pyzmq is a development version, inf will be appended after the third integer.

zmq.has(capability)#

Check for zmq capability by name (e.g. ‘ipc’, ‘curve’)

New in version libzmq-4.1.

New in version 14.1.

zmq.device(device_type, frontend, backend)#

Start a zeromq device.

Deprecated since version libzmq-3.2: Use zmq.proxy

Parameters
  • device_type ((QUEUE, FORWARDER, STREAMER)) – The type of device to start.

  • frontend (Socket) – The Socket instance for the incoming traffic.

  • backend (Socket) – The Socket instance for the outbound traffic.

zmq.proxy(frontend, backend, capture)#

Start a zeromq proxy (replacement for device).

New in version libzmq-3.2.

New in version 13.0.

Parameters
  • frontend (Socket) – The Socket instance for the incoming traffic.

  • backend (Socket) – The Socket instance for the outbound traffic.

  • capture (Socket (optional)) – The Socket instance for capturing traffic.

zmq.proxy_steerable(frontend, backend, capture, control)#

Start a zeromq proxy with control flow.

New in version libzmq-4.1.

New in version 18.0.

Parameters
  • frontend (Socket) – The Socket instance for the incoming traffic.

  • backend (Socket) – The Socket instance for the outbound traffic.

  • capture (Socket (optional)) – The Socket instance for capturing traffic.

  • control (Socket (optional)) – The Socket instance for control flow.

zmq.curve_public(secret_key)#

Compute the public key corresponding to a secret key for use with zmq.CURVE security

Requires libzmq (≥ 4.2) to have been built with CURVE support.

Parameters

private – The private key as a 40 byte z85-encoded bytestring

Returns

The public key as a 40 byte z85-encoded bytestring.

Return type

bytestring

zmq.curve_keypair()#

generate a Z85 key pair for use with zmq.CURVE security

Requires libzmq (≥ 4.0) to have been built with CURVE support.

New in version libzmq-4.0.

New in version 14.0.

Returns

(public, secret) – The public and private key pair as 40 byte z85-encoded bytestrings.

Return type

two bytestrings

zmq.get_includes()#

Return a list of directories to include for linking against pyzmq with cython.

zmq.get_library_dirs()#

Return a list of directories used to link against pyzmq’s bundled libzmq.