ambient2mqtt

README

Ambient2MQTT

Patrick Wagstrom <patrick@wagstrom.net>

October 2021

Overview

This is a simple single binary server that acts as a target for your Ambient Weather station on your local network and relays the data over MQTT so other IoT related devices can make use of it.

You will need to have a newer firmware installed for your Ambient Weather station in order to make use of this feature.

Usage

./ambient2mqtt -config config.toml

Configuration

Configuration is done via a TOML file. Here's a simple example configuration:

[http]
    port = 2466

[mqtt]
    broker_host = "mqtt-broker.lan"
    broker_port = 1883
    broker_username = ""
    broker_password = ""
    client_id = "ambient2mqtt"
    topic_prefix = "weather"
    topic = "ws-2902"

[hass]
    discovery = true
    discovery_prefix = "homeassistant"
    object_id = "ws-2902a"
    object_id = "ws-2902d"
    device_model = "ws-2902d"
    device_name = "ws-2902d"

[influx]
    Hostname = "localhost"
    Port = 8086
    Database = "ambientweather"

Influx requests are 1.x. Each output is optional: leave out [influx] or [timescale] to skip it.

TimescaleDB

[timescale]
    table = "weather"
    station = "edgewater"   # stored in the station column
    # max_queue = 2000      # reports held while the database is unreachable

Each report becomes one row in a wide table. The program reads the table's columns at startup and fills each one from the report key of the same name (converted to the column's type); columns a report lacks are NULL, and report keys without a column are logged once and skipped, so a new station key only needs a new column. Solar radiation above 1,400 W/m² and UV above 12 are sensor glitches and stored as NULL. The table needs time and station columns; PASSKEY (the station's MAC) and dateutc are never stored. The connection comes from the standard libpq environment variables (PGHOST, PGPORT, PGUSER, PGPASSWORD, PGDATABASE, PGSSLMODE), so the config file holds no credentials. The schema used in testing is testSchema in timescale_test.go.

Docker

Multi-arch images (amd64, arm64, arm/v7) are published to ghcr.io/pridkett/ambient2mqtt for each release. The container listens on port 2466; point the station's custom server there (path /data/report/).

License

Licensed under terms of the MIT license