[][src]Crate tokio_zmq

Tokio ZMQ, bringing ZeroMQ to the Tokio event loop

This crate provides Streams, Sinks, and Futures for ZeroMQ Sockets, which deal in structures caled Multiparts. Currently, a Multipart is a simple wrapper around VecDeque<zmq::Message>, but in the future this will be represented as a wrapper around VecDeque<S: zmq::Sendable> with the zmq 0.9 release.

Creating a socket

To get a new socket, you must invoke the Socket builder. The Socket Builder can output a 'raw' Socket, or any specific kind of socket, such as Rep, Req, etc. The result of the builder can be any compatable kind of socket, so specifiying a type is important.

Once you have a socket, if it implements StreamSocket, you can use the socket's .stream() and .recv(), if it implements SinkSocket, you can use the socket's .sink(usize) and .send(Multipart).

Without further ado, creating and using a socket:

extern crate zmq;
extern crate futures;
extern crate tokio;
extern crate tokio_zmq;

use std::sync::Arc;

use futures::{Future, Stream};
use tokio_zmq::{prelude::*, Socket, Pub, Sub, Error};

fn run() -> Result<(), Error> {
    // Create a new ZeroMQ Context. This context will be used to create all the sockets.
    let context = Arc::new(zmq::Context::new());

    // Create our two sockets using the Socket builder pattern.
    // Note that the variable is named zpub, since pub is a keyword
    let zpub = Pub::builder(Arc::clone(&context))

    let sub = Sub::builder(context)

    // Create our simple server. This forwards messages from the Subscriber socket to the
    // Publisher socket, and prints them as they go by.
    let runner = zpub
        .and_then(|(zpub, sub)| {
                .map(|multipart| {
                    for msg in &multipart {
                        if let Some(msg) = msg.as_str() {
                            println!("Forwarding: {}", msg);

    // To avoid an infinte doctest, the actual tokio::run is commented out.
    // tokio::run(runner.map(|_| ()).or_else(|e| {
    //     println!("Error: {}", e);
    // })?;



This module contains the code that makes Tokio ZMQ Asynchronous. There's the future module, which defines Request and Response futures for ZeroMQ Sockets, the stream module, which defines receiving data from a socket as an asychronous stream, and the sink module, which defines sending data to a socket as an asychronous sink.


Provide useful types and traits for working with Tokio ZMQ.



The DEALER SocketType wrapper type.


This type is used for receiving and sending messages in Multipart groups. An application could make using this easier by implementing traits as follows:


The PAIR SocketType wrapper type.


The PUB SocketType wrapper type


The PULL SocketType wrapper type


The PUSH SocketType wrapper type


The REP SocketType wrapper type


The REQ SocketType wrapper type


The ROUTER SocketType wrapper type


Defines the raw Socket type. This type should never be interacted with directly, except to create new instances of wrapper types.


The SUB SocketType wrapper type


The XPUB SocketType wrapper type


The XSUB SocketType wrapper type



Defines the error type for Tokio ZMQ.