Expose Ignition Tags for R/W

Hello All, I have made a custom Python Paho MQTT client that can connect to the CirrusLink MQTT Server that I have installed on my Ignition Gateway. I would like to know how to setup my tags so that I can pub/sub to read and write tag values using my custom client by connecting to the local gateway ip and MQTT port.

Hi @abi17124, I would start by looking at the Transmission module from CirrusLink.

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Hi @matthew.ayre,
Thanks for your reply! I have setup my Transmission module, and I do see a folder called MQTT Tags in my Designer and verified that the Transmitter was in fact connected to the server (Shows 1 of 1 connected), I was also able to successfully connect to my MQTT server with my python script, however I am unsure what topic I should subscribe to get info at least from the example tags. Is it the Sparkplug ID or Tag Path listed in the Example Transmitter section?

Hi @abi17124, the topic will be the path listed in the Sparkplug ID column I believe.

I tried that yesterday and unfortunately that did not work, I used the SparkPlug ID and then appended the tag path on it to subscribe to the tag. I also looked at CirrusLinks MQTT Transmission setup doc which seems to have a different or older configuration. I’ve listed my script subscribe line, transmitter info, and designer tag structure below. I know its connected because I see the MQTT Distributor module shows the connection come up when my python script connects. Not sure where to go from here :confused:

Tag Structure

I’m not familiar with the specifics of your client, but I can tell you that from an MQTT perspective, Sparkplug messages originate from a spBv1.0 root topic. The Sparkplug Spec is a good and relatively short read.

EDIT: take a look at page 12 that describes the topic namespace:


@kcollins1 , thanks for the reply. I believe I was running into this issue because my python client wasn’t of any Sparkplug spec, I was able to fix my problem following this guide that shows how you can setup a gateway event script to publish to a specific topic for non-Sparkplug clients, leaving it here for people who may have the same problem.


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