Welcome to pyzmq-wrapper’s documentation!¶
pyzmq-wrapper is a set of classes that provide wrappers over the zmq code - these aim to serve the 80% cases where the developers just want to start a publisher or subscriber withut having to worry about how the zmq connections are made or what flags are to be used for each message. The publishers and the subscribers created by pyzmq-wrapper use the default values for all flags. The only assumption made is that the subscribers will be in non-blocking mode, so that you can use the subscriber in a thread and can shut it down easily. Also the subscriber provides a callback - freeing you from having to loop through the receiving process.
The sock() method on the publishers and subscribers gives access to the underlying zmq socket object so that you can use that for sending messages which require you to set certain flags.
Installation¶
You can install this using one of the following:
pip install pyzmq-wrapper
easy_install pyzmq-wrapper
Getting started¶
The following entities are provided to abstract the user from the zmq code.
Publisher¶
A simple pulisher can be started on a port as shown below. This object can then be used to send messages - with or without a topic:
from zmqwrapper import *
p=publisher('tcp://127.0.0.1:5555')
p.publish("hello",RAW)
#greeting is the topic
p.publish("hello",MULTIPART,"greeting")
Subscriber¶
A simple subscriber can be created by passing a port, a list of topics, a callback and message type. The callback is executed for every message that is received on the topic:
from zmqwrapper import *
#define the callback
def process_greeting(topic,message):
print message
#create the subscriber
s=subscriber('tcp://127.0.0.1:5555',['greetings'],process_greeting,MULTIPART)
#and start it so that we can process the messages
s.start()
Requestor¶
A simple requestor can be created by passing in the address, callback for replies and the message type. The callback receives the requestor again so that you can make additional requests if needed:
from zmqwrapper import *
def foo(message,requestor):
print message
rq=requestor('tcp://127.0.0.1:5555',foo,JSON)
rq.start()
rq.request('test message',JSON)
Replier¶
A simple replier can be created by passing in the address, callback for requests and the message type. The callback receives the replier so that you can send back he response:
from zmqwrapper import *
import time
def foo(message,replier):
print message
replier.reply(message)
rp=replier('tcp://127.0.0.1:5555',foo,JSON)
rp.start()
time.sleep(5)
Producer¶
A simple producer can be started on a port as shown below. This object can then be used to push messages:
from zmqwrapper import *
p=producer('tcp://127.0.0.1:5555')
p.push("hello",RAW)
Consumer¶
A simple consumer can be created by passing a port,a callback and message type. The callback is executed for every message that is received on the topic:
from zmqwrapper import *
#define the callback
def process_greeting(message):
print message
#create the consumer
c=consumer('tcp://127.0.0.1:5555',process_greeting,RAW)
#and start it so that we can process the messages
c.start()