TAWES to MQTT

About

This script fetches weather data from TAWES (Teil Automatisches Wetter Erfassungs System) of ZAMG, extracts data for a defined station and publishes it via MQTT (Formatted for automatic discovery in Home Assistant)

Installation

Fetch source via git:

git clone https://github.com/peletiah/tawes2mqtt.git
cd tawes2mqtt/

Prepare the virtualenv and activate environment:

virtualenv -p python3 . 
source bin/activate

Install requirements with pip:

pip install -r requirements.txt

Configuration

In tawes2mqtt.py edit the settings according to your requirements:

Weather station and weather data

This script only publishes weather data from a single station. The setting DESIRED_STATION defines which station is selected (Default: 11331, which is the weatherstation at Klagenfurt/Flughafen). The station-ID can be found in the first column of the TAWES csv-file from ZAMG's website.

• DESIRED_STATION defines the ID of the station of which weather data should be published
• IGNORE KEYS defines weather parameters that should not be published via MQTT(e.g. the station's ID and name, height above sea level, peak wind speed, ...)

MQTT configuration

• MQTT_BROKER_IP defines the IP-address of the MQTT-Broker we publish to
• BASE_TOPIC defines a string that is prepended to the MQTT-topic
• BASE_ID defines a string that is prepended to the weather-parameter-keys (e.g. humidity becomes my_base_id_humidity)
• NAME_SUFFIX defines a string that is affixed to parameter name (e.g. Relative Humidity becomes Relative Humidity my name suffix)
• MQTT_QOS define the MQTT QOS level - default is 2, which guarantees the delivery of the message (see Understanding MQTT QOS Levels
• MQTT_RETAIN if True, tells the broker to keep the last message until overwritten (see MQTT Retain Explanation)

STATION_PARAMS

The STATION_PARAMS-dictionary provides mapping of data-format from the keys in the TAWES csv-file to a more programmer-friendly format (e.g. LDstat hPa is mapped to relative_pressure). Additional key-value-pairs for each parameter are added for convenience. Most of these additional values are specifically for the Home Assistant MQTT discovery

STATION_PARAMS

param_name - distinguishable and human-readable name of the parameter (e.g. relative_pressure)

 key - ZAMG TAWES column name (e.g. LDstat hPa)

 name - Name of the parameter, used for "entity name" in Home Assistant

 device_class - Defines the entity icon that is used in Home Assistant (see Device Class)

 unit - Defines the unit of the parameter, used as the unit-option in Home Assistant

Execution

The script can be executed manually like this:

/my/virtualenv/bin/python /my/virtualenv/tawes2mqtt.py

Or through a cronjob (Notice: ZAMG publishes new data ~20 minutes past the full hour, to have some leeway the script is executed every 30 minutes past the full hour):

30 * * * * myuser /my/virtualenv/tawes2mqtt/bin/python /my/virtualenv/tawes2mqtt/tawes2mqtt.py

Debugging

Log messages

Logging can be enabled by setting LOGLEVEL to logging.DEBUGGING (Default: logging.WARNING)

MQTT messages

To verify that MQTT messages are sent and contain the desired content, you can use the Mosquitto client:

mosquitto_sub -h <mqtt_broker_ip> -t "#" -F  %J

-h - defines the hostname or IP of your mqtt broker -t - defines the topic ("#" listens to everything) -F %J - specifies the output printing format, %J uses the JSON output format with non-quoted and non-escaped payload

See "Using The Mosquitto_pub and Mosquitto_sub MQTT Client Tools- Examples" for more information.