ZMQ event publisher in Jenkins doesn't send a notification - jenkins

Question

I have been trying to figure out what is wrong with my Jenkins ZMQ-event-publisher configuration for more than 23 hours and have given up. Hopefully, you may have an idea what I am doing wrong.
I've installed Jenkins with ZMQ-event-publisher plugin and under Manage Jenkins->Configure System checked Enable on all Jobs (Note TCP port to publish on is set to 8888).
Created a new job, checked Check if ZMQ events should be published for this project and clicked on Save.
I have written a Python script using pyZMQ
#!/usr/bin/env python
import zmq
port = "8888"
context = zmq.Context()
socket = context.socket(zmq.SUB)
socket.connect("tcp://localhost:%s" % port)
socket.setsockopt(zmq.SUBSCRIBE, '')
print "Jenkins... waiting..."
string = socket.recv()
print "recv =>", string
Executing the above script on the Jenkins machine + running the Jenkins job.
Unfortunately, the script doesn't receive any ZMQ message from Jenkins.
Trying to capture the ZMQ message using either tcpdump -i eth0 'port 8888' or tcpdump -i lo 'port 8888' didn't help too.
In addition to that, looking at the /var/log/jenkins/jenkins.log, I get:
Sep 25, 2014 8:54:47 PM org.jenkinsci.plugins.ZMQEventPublisher.ZMQRunnable bindSocket
INFO: Binding ZMQ PUB to port 8888
Sep 25, 2014 8:54:48 PM hudson.model.Run execute
INFO: MyJob #18 main build action completed: SUCCESS
Moreover, netstat -ntlp verifies that
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 :::8888 :::* LISTEN 31/java
tcp 0 0 :::57467 :::* LISTEN 31/java
tcp 0 0 :::8009 :::* LISTEN 31/java
tcp 0 0 :::59373 :::* LISTEN 31/java
tcp 0 0 :::8080 :::* LISTEN 31/java
So, what am I doing wrong?
There is no good explanation on how to configure correctly the Jenkins ZMQ plugin and looking at the plugin code doesn't reveal much.
Your help will be more than appreciated.
Thanks.
EDIT : Dave's suggestion was great, but it hasn't fixed the problem, yet.
EDIT 2: It looks like it fails because Jenkins has been running from a Docker container and I've forgotten to expose all its ports. Nevertheless, It looks like Dave's suggestions does fix the problem. Yay!!!

Answer 1

From the ZMQ Guide:
Note that when you use a SUB socket you must set a subscription using zmq_setsockopt() and SUBSCRIBE
I suspect that your subscriber script is not seeing events because you need to set the subscribe filter. As described on the zmq_setsockopt page, setting the filter to the empty string subscribes to all messages.
Try adding:
socket.setsockopt(zmq.SUBSCRIBE, '')