Convert Twilio JSON responses to XML

twilio_json_response_to_xml.ex

#!/usr/bin/env elixir

Mix.install([
  :jason,
  :xml_builder
])

[input] = System.argv()

defmodule Helper do
  def map_to_elements(map) do
    map
    |> Enum.reduce([], fn
      {key, map}, list when is_map(map) ->
        [XmlBuilder.element(format_key(key), [], map_to_elements(map)) | list]

      {key, value}, list ->
        [XmlBuilder.element(format_key(key), [], value) | list]
    end)
    |> Enum.reverse()
  end

  defp format_key(key) do
    key |> Macro.camelize() |> String.to_atom()
  end
end

elements =
  input
  |> File.read!()
  |> Jason.decode!()
  |> Helper.map_to_elements()

XmlBuilder.document(:TwilioResponse, [XmlBuilder.element(:Call, [], elements)])
|> XmlBuilder.generate()
|> IO.puts()