zmqchans lets you work with ZeroMQ sockets using core.async channels in a thread-safe manner.
ZeroMQ is a great networking/IPC library and core.async is a great inprocess communication library. Unfortunately they don't work together very well without some glue code. Without zmqchans or alternatives you have to create ad hoc solutions for every project dealing with the separate communication with ZMQ sockets. They cannot easily be added to your main socket polling loop, you need a separate thread of execution for that. With zmqchans all of this can be achieved in one or two lines of code and then you have ZMQ sockets right there on your clojure.core.async toolbox.
There are some other open source projects that have provided their own solutions for this problem. Especially Kevin Lynagh's zmq-async library has been a great reference and source of inspiration when creating this library. Due to an architectural oversight it's easy to create deadlocks in that library. That was a reason why an improved design was required.
Improvements over zmq-async:
- Deadlock free design: no two-way communication between injection thread and ZMQ socket polling thread.
- Easy to use API with minimal boilerplate.
- Full thread-safe access to the sockets that have been added to the ZMQ polling thread, not only message delivery.
[zmqchans "0.3.4"]If you are using linux with x86_64 architecture that's all you need to do. The artifact comes with cljzmq and libzmq deployed in a .jar file. For information about the exact binary versions, please refer to project.clj.
If you are using another OS / architecture you need to build jzmq. Have a look at INSTALL.md for more information.
(with-temp-context
(let [pub (socket :pub "@tcp://*:*")
sub (doto (socket :sub) (connect! pub) (subscribe! ""))
ch (chan)]
(go-loop []
(let [[v _] (alts! [ch (:out sub)])]
(when v
(println (String. v))
(recur))))
(send! pub "broadcast")
(>!! ch "from channel")))Please refer to the wiki.
You can send email directly to [email protected] if you need assistance. If you have feature ideas or find some bugs please use the github's issue feature.
Thanks to Kevin Lynagh (@lynaghk) for the initial idea and implementation (https://github.com/lynaghk/zmq-async). Thanks to those who helped him during that process, mentioned in https://github.com/lynaghk/zmq-async#thanks.
Copyright © Sebastian Jylanki. Some functionality copied from Kevin Lynagh's zmq-async library with or without modifications.
Distributed under the Eclipse Public License either version 1.0.