🌐 MQTT Topics and Environment Variables

Status Topic Prefix

By default, the bridge publishes its connection status to:

bmw/status

If you want a different topic prefix (for example if you have multiple cars or bridges),
you can configure it using this environment variable in your .env file:

LOCAL_PREFIX=mycar/

The bridge will then publish:

mycar/status

and all other MQTT messages (e.g. raw, vehicles, etc.) under the same prefix.

status:

Reports the connection state to the BMW MQTT broker (true = connected, false = disconnected).

true is published immediately when the connection is established.

false is published only after STATUS_STABLE_DELAY seconds of continuous disconnect (default: 5).

Set STATUS_STABLE_DELAY=0 to disable the delay (instant switching).

This debounce avoids brief drops (e.g., during token refresh) from causing flicker in clients that monitor the status.

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Split Topics (Structured JSON Publishing)

By default, the bridge republishes BMW CarData messages exactly as received
into a local topic of the form:

bmw/raw/<VIN>/<eventName>

To make integration easier for automation systems (like Home Assistant, Node-RED, etc.),
you can optionally enable split topics, which publish each data field under its own sub-topic:

add to your .env file:

SPLIT_TOPICS=1

This will create additional messages like:

bmw/vehicles/<VIN>/fuelPercentage {"value":62.5,"unit":"%","timestamp":1739790000}
bmw/vehicles/<VIN>/range_km       {"value":420}
bmw/vehicles/<VIN>/position       {"value":{"lat":48.1,"lon":11.6},"timestamp":1739790100}