Additional message is sent to process when request times out

[vfsoraki]

I use a timeout of 500ms for a call to an external service.

Sometimes the request times out and that's fine, but then my GenServer recieves a message of the following format. Since I do not handle it, it crashes :(

[error] AdExchange.OpenRTB.V24Worker #PID<0.1658.0> received unexpected message in handle_info/2: {#Reference<0.640795280.3317170178.75561>, {:ok, '200', [{'Date', 'Fri, 23 Feb 2018 16:47:29 GMT'}, {'Content-Type', 'application/json; charset=utf-8'}, {'Server', 'Kestrel'}, {'Transfer-Encoding', 'chunked'}], '<some_json_result>''}}

Seems like it sends the result, when I don't need it anymore.

I read docs, and I am not using async requests for sure.

Is this an expected behaviour?

HTTPotion is 3.1.0.

[valpackett]

Hi. That's weird. HTTPotion would never send something that looks like {:ok, …} — async responses are %HTTPotion.AsyncSomething{…}. { :ok, status_code, headers, body } is the format of synchronous responses from ibrowse, which is handled in handle_response.

How does the request call look like?

[vfsoraki]

This is how I send and handle response.

  defp request(encoded_obj, url, apikey) when is_bitstring(encoded_obj) do
    headers =
      if apikey,
        do: [{"Content-Type", "application/json"}, {"apikey", apikey}],
        else: [{"Content-Type", "application/json"}]

    options = [body: encoded_obj, timeout: @timeout, body: encoded_obj, headers: headers]

    url
    |> HTTPotion.post(options)
    |> handle_response()
  end

  defp request(nil, _url, _apikey) do
    {:error, :nil_request}
  end

  defp handle_response(%HTTPotion.Response{status_code: 200, body: body}) do
    {:ok, Helper.decode!(body)}
  end

  defp handle_response(%HTTPotion.Response{status_code: 204}) do
    {:error, :empty_result}
  end

  defp handle_response(%HTTPotion.Response{status_code: 403}) do
    {:error, :unauthorized}
  end

  defp handle_response(%HTTPotion.ErrorResponse{message: message}) do
    {:error, message}
  end

  defp handle_response(resp) do
    Logger.warn("Unkown response received: #{inspect(resp)}")
    {:error, :unknown_response}
  end

I know it shouldn't, but the data in message looks like it comes from there. And I did not see this error before, until now that I switched to HTTPotion.

[vfsoraki]

I'm still having this issue. Any idea on how can I track this?

[valpackett]

There are many debugging tools. I don't know which is the best one.

[philipgiuliani]

I'm having the same issue. My Genserver crashes because it sometimes receives an unhandled message from HTTPotion.

It seems this issue comes from ibrowse. See the following ticket: cmullaparthi/ibrowse#36