Snippet showing how to dump request headers into response as JSON, put in controller

phoenix_headers_snippet.ex

  def mapify({k,v}, m) do
      Map.put(m, k, v)
  end
  
  def show(conn, %{"id" => id, "as" => "headers"}) do
    resp_body = conn.req_headers
    	 |> List.foldl(Map.new(), &mapify/2)
	 |> Poison.encode!
    send_resp(conn, 200, resp_body)
  end