Settings Weatherflow Tempest

A library for handling the data from the LAN API for WeatherFlow weather stations.

Online docs found at https://hexdocs.pm/weatherflow_tempest.
Code and bug reports are at https://github.com/joshproehl/weatherflow_tempest.

Current Weatherflow UDP API version targeted is 171.

Supported devices:

• Air/Sky
• Tempest

Yes, the library is called "weatherflow tempest". Why it was created that way, when it has always supported both Tempest and the earlier device, is lost to time. Maybe because it was going to handle a veritable tempest of UDP packets?

Installation

Add weatherflow_tempest to your list of dependencies in mix.exs:

def deps do
  [
    {:phoenix_pubsub, "~> 2.0"}, # Only required if using PubSub broadcasts
    {:weatherflow_tempest, "~> 1.0.0"}
  ]
end

and fetch your dependencies with

$ mix deps.get

Usage

The intended way to use the library is to configure it to use a Phoenix.PubSub instance, let it auto-start the client, and then subscribe to the data via Phoenix.PubSub.

# In your config file:

config :weatherflow_tempest, pubsub_name: MyApp.PubSub

######################################
# Example PubSub usage in a LiveView #

def mount(_params, _session, socket) do
  WeatherflowTempest.PubSub.subscribe_to_udp_events()
  {:ok, socket}
end

def handle_info({{:weatherflow, event_type}, event_data}, socket) do
  IO.puts("Got a \#\{event_type\} message!")
  # Update your LiveView socket with the data!
  {:noreply, socket}
end

The choice to use Phoenix.PubSub was made because re-implementing PubSub to the same level would be foolish, and also the primary use of this library is very likely to display the data, probably in something like a Phoenix LiveView.

However, if for some reason you need more direct usage of the data, using callback functions is also supported. To do this you must configure the library not to auto-start the Client, and then manually start and supervise the Client.

# In your config file:

config :weatherflow_tempest, callbacks_only: true

#######################################
# Example usage via Callback function #

def handle_weatherflow_event(event_type, event_data) do
  # do something with the data received from the event
end

{:ok, pid} = WeatherflowTempest.Client.start_link([callback_func: &handle_weatherflow_event/2])

Full configuration and usage for both methods can be found in the WeatherflowTempest.Client docs.

You can get the latest data heard from the station via WeatherflowTempest.get_latest/0, which will return a map containing the most recent data that has been heard from every Weatherflow device on the LAN, but in practice you will probably want to use either the PubSub broadcasts or callback functions to handle events as they occur, and only use WeatherflowTempest.get_latest/0 to seed initial values to your app. (When starting a new LiveView page for example.)

Note

While it is technically possible to start the application with neither a PubSub name configured nor a callback function given, it is not the intended way to use the library.
In this case the Client will still start, but you will only be able to access the data via the WeatherflowTempest.get_latest/0 function, and will not be able to receive individual events.

The payload for each event is transformed from the UDP API strucure by WeatherFlowTempest.Client, but in short it will be a map containing all data returned by the API as key/value pairs. Examples of returned data can be found in Event Examples.