Per-Service Formatters

[ignorantbliss]

I'm trying to set up my system to send notifications from inside an MQTT topic, but I want to send those notifications to two different destinations which require two different formats.

For example, let's say I want desktopnotify and file.

[/my/mqtt/folder/#]
format = my_formatter()
targets = {
	'/#': ['file:logfile', 'desktopnotify:desktop']
	}

How to I get a different format for the two different services, when I can only have one INI section per topic? It would be easy if I could add a second [/my/mqtt/folder/#], but that's not possible.

It would also be simple if the function call to the formatting function included an indication of which service the formatting was being sent to - this would make it really easy to customise the format to suit each individual destination.

Google Gemini suggests a technique that I can't find in the documentation and doesn't seem to work - it has the idea of putting in per-service formatters, like this...

[/my/mqtt/folder/#]
file:logfile.format = "ALERT: {name}"
desktopnotify:desktop.format = "{\"title\": \"Alert\",\"message\": \"{name}\"}"
targets = {
	'/#': ['file:logfile', 'desktopnotify:desktop']
	}

This would resolve my issue, but as I mentioned, I can't seem to get it to work.

[ignorantbliss]

ignorantbliss@3c9e223 - This update adds functionality similar to what is described above.

In the topic configuration, you can provide per-topic, or per-source overrides to the transform parameters.

Override names are tried in the following order...
[source]:[target].[transform]
[source].[transform]
[target].[transform]
[transform]

[/my/mqtt/folder/#]
format="{name}"
file = "ALERT: {name}"
desktopnotify:desktop.format = notification_format()
targets = {
	'/#': ['log:info','file:logfile', 'desktopnotify:desktop']
	}

In the above example, the log source would just contain "{name}", the file source would have "Alert {name}", and the desktop notification would call the user-provided 'notification_format()' function.

[amotl]

Hi. Can you use the templated targets feature, which can be used to interpolate transformation values into target descriptors?

[frigate/+/+/snapshot]
targets = store-image:{camera}-{label}

If your patch is differently, we will be happy to accept the corresponding improvement to the code base. Can you stage a pull request and add documentation about your improvement in a similar spirit like the templated target feature demonstrates its usage? 🙏