JSON is serialized into Erlang unicode and then passed to a Python process:

defmodule Sandbox do
  def foo(json_data) do
    port =
      :erlang.open_port(
        {:spawn, 'python3 -u lib/Python/Sandbox.py'},
        [:binary, packet: 4]
      )

    execute = fn data ->
      send(port, {self(), {:command, :erlang.term_to_binary({data})}})

      receive do
        {_, {:data, response}} -> :erlang.binary_to_term(response)
      after
        60000 ->
          {:error, :timeout}
      end
    end

    {_, results_string} = execute.(json_data)

    Print.text("sending JSON data, python result: #{results_string}")
  end
end

Example of what the Python process receives:

json_data = "<<131, 109, 0, 0, 0, 212, 123, 34, 97, 109, 111, 117, 110, 116, 95, 97, 115, 115, 101, 116, 34, 58, 34, 87, 65, 86, 69, 83, 34, 44, 34, 110, 111, 114, 109, 97, 108, 105, 122, 101, 100, 95, 97, 109, 111, 117, 110, 116, 34, 58, 52, 54, 54, 57, 55, 49, 51, 55, 56, 44, 34, 111, 114, 100, 101, 114, 95, 108, 105, 102, 101, 116, 105, 109, 101, 34, 58, 54, 49, 44, 34, 112, 114, 105, 99, 101, 34, 58, 48, 46, 48, 56, 56, 54, 51, 48, 48, 55, 44, 34, 112, 114, 105, 99, 101, 95, 97, 115, 115, 101, 116, 34, 58, 34, 72, 90, 107, 49, 109, 98, 102, 117, 74, 112, 109, 120, 85, 49, 70, 115, 52, 65, 88, 53, 77, 87, 76, 86, 89, 116, 99, 116, 115, 78, 99, 103, 54, 101, 50, 67, 54, 86, 75, 113, 75, 56, 122, 107, 34, 44, 34, 117, 105, 100, 34, 58, 34, 50, 48, 50, 48, 45, 49, 49, 45, 50, 51, 32, 50, 48, 58, 48, 51, 58, 53, 49, 46, 48, 48, 53, 50, 49, 53, 90, 116, 55, 71, 79, 79, 54, 49, 71, 89, 117, 112, 119, 78, 117, 122, 115, 109, 102, 52, 119, 83, 119, 34, 125>>"

To deserialize this into a Python dictionary the “<<” and “>>” characters need to be stripped off, all of the numbers need to be converted from strs to ints, and then the new list of ints needs to be iterated over to decode it into UTF-8 characters.

Is there a more efficient way to pass JSON from Elixir to Python such that it’s readily parsed by a Python process?