Debugging Plug as a last resort for debugging nasty production issue in Elixir/Phoenix/AWS ECS Fargate

debug.ex

defmodule MyApp.Plugs.Debug do
  @behaviour Plug

  require Logger

  def init(default), do: default

  def call(conn, _) do
    case conn.request_path do
      "/path/to/error" ->
        Logger.debug inspect(conn)
      _ ->
        nil
    end

    conn
  end
end