Fix Fully Kiosk Browser MQTT event callbacks with non-standard event topics

[cgarwood]

Proposed change

Adjust the handling of Fully Kiosk Browser MQTT event callbacks.
Fully Kiosk Browser allows you to set a custom MQTT topic for events. By default, this topic is: $appId/event/$event/$deviceId where $appId translates to fully, $event translates to the name of the event, and $deviceId is the ID of the device.

If a user configures a custom event topic without the $event placeholder, all of the events hit the same topic, so every event will trigger the callback regardless of what the event actually is.

The payload also contains the event name, so I adjusted the callback function to check that the event name in the payload is correct before firing the callback.

Tested with Fully Kiosk Browser 1.54.1 (current) and 1.42.5 and working.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Bad behavior of Fully Kiosk Browser with the new 2023.12.0 HA core  #105263
• This PR is related to issue:
• Link to documentation pull request:

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[MartinHjelmare]

All the mqtt data and topic parsing really belongs in the 3rd party library. Please move it there in a follow up PR. Have the library accept callbacks for subscription (and publishing) but do all the details in the library. Ie give the library handles to be able to use the MQTT transport of Home Assistant but keep the details about how those are used in the library.