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(), if it implements SinkSocket, you can use the socket's .sink(), and if it implements FutureSocket, you can use the send and recv methods.

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))
        .bind("tcp://*:5561")
        .build()?;

    let sub = Sub::builder(context)
        .bind("tcp://*:5562")
        .filter(b"")
        .build()?;

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

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

Re-exports

pub use self::socket::types::Dealer;

pub use self::socket::types::Pair;

pub use self::socket::types::Pub;

pub use self::socket::types::Pull;

pub use self::socket::types::Push;

pub use self::socket::types::Rep;

pub use self::socket::types::Req;

pub use self::socket::types::Router;

pub use self::socket::types::Sub;

pub use self::socket::types::Xpub;

pub use self::socket::types::Xsub;

pub use self::socket::Socket;

Modules

async	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.
file	This module contains definitions for the ZmqFile type, a small wrapper around a RawFd so tokio_file_unix can interact with it.
prelude	Provide useful types and traits for working with Tokio ZMQ.
socket	This module contains useful types for working with ZeroMQ Sockets.

Structs

Multipart

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

Enums

Error

Defines the error type for Tokio ZMQ.