example_device_location.ex

defmodule Parser do
  use Platform.Parsing.Behaviour
  require Logger

  #
  # Example parser for using device location in reading.
  #
  # Name: Example parser for using the device location
  # Changelog:
  #   2019-09-30 [jb]: Initial implementation
  #

  def preloads() do
    [device: []]
  end

  # Using matching
  def parse(<<1, 2, 3>>, %{device: %{location: %{coordinates: {lon, lat}}}} = _meta) do
    %{
      gps_lat: lat,
      gps_lon: lon
    }
  end

  # Using get()
  def parse(<<1, 2, 3>>, meta) do
    %{
      gps_lat: get(meta, [:device, :location, :coordinates, 1]),
      gps_lon: get(meta, [:device, :location, :coordinates, 0])
    }
  end

  def parse(payload, meta) do
    Logger.warn(
      "Could not parse payload #{inspect(payload)} with frame_port #{
        inspect(get_in(meta, [:meta, :frame_port]))
      }"
    )

    []
  end

  def tests() do
    [
      {:parse_hex, "010203", %{device: %{location: %{coordinates: {9.99, 53.55}}}},
       %{gps_lat: 53.55, gps_lon: 9.99}}
    ]
  end
end