WhiteBoard Coder: ZeroMQ with Python, quick getting started guide

Quick ZeroMQ with Python – notes 001

Created 06/28/2012

T. Patrick Bailey

I am currently trying to wrap my head around what ZeroMQ is and what I can do with it. This is a quick tutorial I wrote on getting it working with Python.

I was inspired by this video showing zeroMQ working in a demo ~ 3:12 into the video http://www.youtube.com/watch?v=_JCBphyciAs&feature=related [1]

First we need to download ZeroMQ for python and get it working… I struggled with this for a while but finally got it working. I am using Ubuntu 10.04 as my OS, here are the steps I took. I used the following sites to come up with this install procedure https://gist.github.com/574656 [2], http://johanharjono.com/archives/633 [3] http://www.hacksparrow.com/ubuntu-how-to-install-easy_install.html [5]

Install server tools

> sudo apt-get update

> sudo apt-get upgrade

> sudo apt-get install build-essential

> sudo apt-get install zlib1g-dev

> sudo apt-get install libtool autoconf automake

> sudo apt-get install uuid-dev g++

Get the web address for the latest zeromq download

http://www.zeromq.org/intro:get-the-software and right click on the POSIX tarball and copy the address to be used in the following commands with wget

> cd /tmp

> wget http://download.zeromq.org/zeromq-2.2.0.tar.gz

> tar -zvxf zeromq-2.2.0.tar.gz

> cd zeromq-2.2.0

> ./configure

> make

> sudo make install

If you are using Ubuntu 12.04 you can do this much easier following these instructions http://ridingpython.blogspot.com/2012/05/installing-zeromq-python-lib-pyzmq-on.html [4]

Get python tools for zeroMQ

> sudo apt-get install python-software-properties

> sudo add-apt-repository ppa:chris-lea/zeromq

> sudo add-apt-repository ppa:chris-lea/libpgm

> sudo apt-get update

> sudo apt-get install libzmq1 libzmq-dev

> sudo apt-get install python-dev

> sudo apt-get install python-setuptools

> sudo easy_install pyzmq

That should do it, now for a simple test with a few python scripts.

I am new to ZeroMQ and to python so bear with me on my examples.

First make a zmq socket for sending.

server-main:~> python

Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41)

[GCC 4.4.3] on linux2

Type "help", "copyright", "credits" or "license" for more information.

>>> import zmq

>>> ctx = zmq.Context()

>>> sock = ctx.socket(zmq.DOWNSTREAM)

>>> sock.bind("tcp://127.0.0.1:12345")

This will bind it to the 127.0.0.1 port 12345 and is ready to send

Now in another terminal (on the same machine) make something to receive

server-main:~> python

Python 2.6.5 (r265:79063, Apr 16 2010, 13:09:56)

[GCC 4.4.3] on linux2

Type "help", "copyright", "credits" or "license" for more information.

>>> import zmq

>>> ctx = zmq.Context()

>>> sock = ctx.socket(zmq.UPSTREAM)

>>> sock.connect("tcp://127.0.0.1:12345")

>>> while True:

... print sock.recv()

...

This will bind on the same port and wait to receive in a loop. I had to hit enter twice after I typed in the recv line (I am new to python scripting and did not catch that for a while)

Now back to the sending program execute the following line

>>> sock.send(“Hello World”)

And in the receiver we see…