cobblr 0.1.4

pyzmq broker and client handlers with name based addressing

cobblr

This is a package for simple client-broker and client-client communications using the ZeroMQ package for python.

It is designed for M2M communications and easy passing of data between software modules. Each client program runs asynchronously in a single new background thread. Clients are addressed with a unique name and once registered with a broker can request new communications.

This package was built as part of the Digital Manufacturing on a Shoestring Project.

This library is in development.

Please check back soon!

API

from cobblr.cobblr import CobblrBroker
cb = CobblrBroker

Create and start a broker

from cobblr.cobblr import CobblrClient
cl = CobblrClient("cl_test")

Create and start a client named cl_test

cl.register()

Register client cl_test with the running broker

from cobblr.cobblr import CobblrClient
cr = CobblrClient("cr_test")
cr.register()

Create, start and register client cr_test

cl.request_connection("cr_test")

Request a connection to client cr_test from client cl_test

connection_list = cl.get_connected()

Populates connection_list with names of connected clients and broker. The broker is always named service.

cl.send_message("cr_test",["string_1", "string_2"])

Sends a message from client cl_test to client cr_test, consisting of two strings.

msg = ["no_msg"]
while msg == ["no_msg"]:
    msg = cr.get_messages()
print(msg)

Loop to read message inbox on client cr_test. Messages will be returned as a list, with each entry a list of [<message number>, <from address>, <message contents>].

The inbox is cleared on reading.

cr.end

Ends client cr_test.

API for pub-sub to be added soon

Features List

• Client name registration at broker
• Single IP space
• Multiple IP and Network support
• Request a connection to another named client
• Request - Response messaging pattern between named clients
• Publish - Subscribe messaging pattern
• Simple state machine with task prioritisation
• Asynchronous background operation
• Smooth shutdown and restart
• Heartbeat for network status and awareness
• Backup broker
• Network configuration save and load
• Message encryption