minty.ex

defmodule Minty do
  defmodule Response do
    defstruct [:status, :headers, :data]
  end

  def request(method, url, opts \\ []) do
    %{scheme: scheme, host: host, port: port, path: path} = URI.parse(url)
    payload = Keyword.get(opts, :payload)
    headers = Keyword.get(opts, :headers, [])

    with {:ok, conn} <- Mint.HTTP.connect(String.to_atom(scheme), host, port),
         {:ok, conn, _ref} <-
           Mint.HTTP.request(conn, method, path, headers, encode!(payload)),
         {:ok, conn, response} <- fetch_response(conn) do
      {:ok, _conn} = Mint.HTTP.close(conn)
      to_response(response)
    end
  end

  defp fetch_response(conn) do
    Mint.HTTP.stream(
      conn,
      receive do
        msg -> msg
      end
    )
  end

  defp to_response([
         {:status, _, status},
         {:headers, _, headers},
         {:data, _, data},
         {:done, _}
       ]) do
    case decode(data) do
      {:ok, json} -> {:ok, %Response{status: status, headers: headers, data: json}}
      {:error, error} -> {:error, error}
    end
  end

  defp decode(response_data), do: Jason.decode(response_data)
  defp encode!(nil), do: ""
  defp encode!(request_payload), do: Jason.encode!(request_payload)
end