MQTT Manual vs Discovery

[beerygaz (Gavin Hill)]

I’ll prefix this post by saying I’m new to HA (coming from Homeseer) and I’m running hassos as a VM on proxmox. I have a dedicated mosquitto broker that is all working.

I have a sprinkler application that sends status updates (ON/OFF) to an mqtt topic. I also have a Paradox alarm panel using the PAI integration (which supports HA discovery).

My questions:

1. Can I mix and match discovery vs manual configuration? (manual for the sprinklers, auto for the alarm)
2. Is there a way to write a “template” for the sprinklers to find all the topics and create entities for them automatically or do I need to manually add each device & associated state topic as a YAML entry in a file?

[petro]

@beerygaz

Can I mix and match discovery vs manual configuration? (manual for the sprinklers, auto for the alarm)

Yes.

@beerygaz

Is there a way to write a “template” for the sprinklers to find all the topics and create entities for them automatically or do I need to manually add each device & associated state topic as a YAML entry in a file?

Not with unknown topics. You can build code based off a known topic structure and force discovery at startup but you need to follow the discovery protocols.

[beerygaz (Gavin Hill)]

Mixing discovery vs manual follow up: Can I override a discovered device - for example all of discovered alarm zones are marked with device_class = “motion” but some are door contacts, but it seems if I change this using the GUI (Configuration/Customisations) they are reset to the discovered values.

EDIT: I think I was just missing the customize: !include customize.yaml line in my config.
2nd EDIT - Nope - even including the customize.yaml seems to have no effect

You can build code based off a known topic structure and force discovery at startup but you need to follow the discovery protocols.

I know a topic structure, so this may be possible, can you point me to a starting point to code my own discovery please?

[123 (Taras)]

You can define an MQTT Sensor (or MQTT Switch, Light, Lock, cover, etc) in YAML or you can create a script to define it via MQTT Discovery.

I provided someone else with an example here:

Manually add MQTT Entities

1. Create an MQTT Light using a script Assuming you have an existing scripts.yaml file, paste this into it and save the file:

Click to reveal scripts

## MQTT Discovery Test example_create: alias: 'Example MQTT Light - Create' sequence: service: mqtt.publish data: topic: 'homeassistant/light/example/config' retain: true payload: > { "name": "Example", "unique_id": &quo…

The script can also be used to override a discovered device. However, you must override all of the discovered device’s configuration and not just one part of it (i.e. you can’t just override its device_class alone).

MQTT Discovery is nothing more than Home Assistant subscribing to all topics beginning with homeassistant. A new entity will be created if the topic is in the correct format, namely something like this:

homeassistant/sensor/hallway_motion/config

and if it contains a payload that is also in the correct format. The format of the topic and payload are described here:

MQTT