Quick reference

This is a Hackergarden project, started during 50th Hackergarden 2025-04-01 at codecentric AG, Industriestraße 3, 70565 Stuttgart, Germany.

Maintained by: Michael Oberdorf IT-Consulting

Source code: GitHub

Container image: DockerHub

Supported tags and respective Dockerfile links

• latest, 1.2.0
• 1.1.1
• 1.1.0
• 1.0.2
• 1.0.0

Summary

The application will make an Open Meteo free weather API call to get weather information for the configured geo coordinates. There are currently two MODES specified:

1. current: will get the current weather
2. tomorrow: will get the weather for tomorrow

The results will be parsed, formatted in JSON and published via MQTT.

JSON output examples

current weather

{
  "location": {
    "latitude": 48.779998779296875,
    "longitude": 8.940000534057617,
    "elevation": 409
  },
  "timezone": {
    "name": "Europe/Berlin",
    "abbreviation": "GMT+1",
    "utc_offset_seconds": 3600
  },
  "current": {
    "time": "2026-01-06T09:45:00+01:00",
    "temperature_2m": -6.849999904632568,
    "relative_humidity_2m": 89,
    "is_day": 1,
    "rain": 0,
    "showers": 0,
    "snowfall": 0,
    "weather_code": 71,
    "cloud_cover": 100,
    "surface_pressure": 967.1641845703125,
    "wind_speed_10m": 2.0364675521850586,
    "wind_direction_10m": 224.99989318847656,
    "wind_gusts_10m": 4.320000171661377,
    "weather_code_text": "Snow fall: Slight intensity"
  },
  "message_timestamp": "2026-01-06T09:59:13.119176+01:00"
}

weather forecast for tomorrow

{
  "location": {
    "latitude": 48.779998779296875,
    "longitude": 8.940000534057617,
    "elevation": 409
  },
  "timezone": {
    "name": "Europe/Berlin",
    "abbreviation": "GMT+1",
    "utc_offset_seconds": 3600
  },
  "tomorrow": {
    "date": "2026-01-07",
    "temperature_2m_mean": -5.241146087646484,
    "temperature_2m_min": -8.211000442504883,
    "temperature_2m_max": -3.510999917984009,
    "rain_sum": 0,
    "showers_sum": 0,
    "snowfall_sum": 0,
    "weather_code": 3,
    "wind_speed_10m_mean": 6.99040412902832,
    "wind_speed_10m_min": 1.9386591911315918,
    "wind_speed_10m_max": 13.10419750213623,
    "wind_direction_10m_dominant": 194.28439331054688,
    "wind_gusts_10m_mean": 13.739999771118164,
    "wind_gusts_10m_min": 5.039999961853027,
    "wind_gusts_10m_max": 25.559999465942383,
    "sunrise": 0,
    "sunset": 0,
    "daylight_duration": 30511.171875,
    "sunshine_duration": 23594.3828125,
    "surface_pressure_mean": 964.9620971679688,
    "surface_pressure_min": 961.7695922851562,
    "surface_pressure_max": 968.2794189453125,
    "relative_humidity_2m_mean": 80.78125,
    "relative_humidity_2m_min": 69,
    "relative_humidity_2m_max": 89,
    "weather_code_text": "Cloudy"
  },
  "message_timestamp": "2026-01-06T09:57:42.813048+01:00"
}

Configuration

Container configuration

The container grab some configuration via environment variables.

Environment variable name	Description	Required	Default value
MODE	The weather selection mode. Currently supported is current and tomorow.	optional	current
LATITUDE	The geo coordinate latitude from where we want to have the weather.	optional	48.72592
LONGITUDE	The geo coordinate longitude from where we want to have the weather.	optional	9.11446
ELEVATION	The ground elevation from where we want to have the weather.	optional
WEATHER_MODELS	The weather model to use.	optional
TZ	The time zone to use to provide timestamps.	optional	UTC
MQTT_CLIENT_ID	A MQTT client identifier.	optional
MQTT_PROTOCOL_VERSION	The MQTT protocol version to use. Currently supported 3 (means 3.1.1) and 5.	optional	3
MQTT_TLS	Use TLS encrypted connection to MQTT broker.	optional	false
MQTT_TLS_INSECURE	Disable TLS certificate and hostname verification.	optional	false
REQUESTS_CA_BUNDLE	Path to certificates of trusted certificate authorities.	optional	/etc/ssl/certs/ca-certificates.crt
MQTT_USERNAME	Username to authenticate to MQTT broker.	optional
MQTT_PASSWORD	Password to authenticate to MQTT broker.	optional
MQTT_PASSWORD_FILE	File that contains the password to authenticate to MQTT broker.	optional
MQTT_SERVER	MQTT broker hostname to connect to.	optional	test.mosquitto.org
MQTT_PORT	MQTT broker TCP port to connect to.	optional	1883
MQTT_RETAIN	Publish MQTT message in retain mode fpr persistance.	optional	false
MQTT_TOPIC	The MQTT topic to publish the weather data.	optional	com/github/cybcon/docker.weather2mqtt.git/weather
CACHE_DIR	Directory used for API request caching.	optional	/app/cache
CACHE_EXPIRY_AFTER_SEC	Cache expiration time in seconds.	optional	600
DEBUG	Enable debug output log.	optional	false

.envrc example

If you use direnv to load your environment automatically.

export TZ="Europe/Berlin"
export REQUESTS_CA_BUNDLE=/etc/ssl/certs/ca-certificates.crt
export DEBUG="true"
export MODE="current"
export LATITUDE="48.72592"
export LONGITUDE="9.11446"
export WEATHER_MODELS="icon_d2"
export MQTT_SERVER="test.mosquitto.org"
export MQTT_PORT="8883"
export MQTT_TLS="true"
export MQTT_TLS_INSECURE="true"
export MQTT_CLIENT_ID="acd2b765-e289-49c1-9884-28826f619d2b"
export MQTT_PROTOCOL_VERSION="5"
export MQTT_TOPIC="github.com/cybcon/docker.weather2mqtt.git/weather"
export CACHE_DIR="../cache"
export CACHE_EXPIRY_AFTER_SEC="600"

Configuration files

The modes (current and tomorrow) are defined in configuration files. That can be found here:

Mode	Configuration file in GIT	Location in the container image
current	./src/app/etc/current.json	/app/etc/current.json
tomorrow	./src/app/etc/tomorrow.json	/app/etc/tomorrow.json

The files specifies the API call request body for Open Mateo. A documentation of the free weather API can be found here: https://open-meteo.com/en/docs.

Python Unit Tests

To trigger the Python unit tests please follow following instrructions after checkout the git repository.

Requirements

pip install -r src/requirements.txt
pip install -r test/requirements.txt

Execute Unit Tests

python -m unittest
pytest
ruff check --select=E9,F63,F7,F82 --target-version=py312 .
ruff check --target-version=py312 .

Donate

I would appreciate a small donation to support the further development of my open source projects.

License

Copyright (c) 2025-2026 Michael Oberdorf IT-Consulting

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.