FFmpex/rambo "invalid command 'nil'" only in one environment

Questions / Help
1

I’m using FFmpex to convert files uploaded through a form. Everything works as expected in my local environment but when deploying to my (Ubuntu Amazon ECS) dev server my execute(command) fails with invalid command 'nil'

    ** (ArgumentError) invalid command 'nil'
        (rambo 0.3.4) lib/rambo.ex:180: Rambo.run/3
        (ffmpex 0.10.0) lib/ffmpex.ex:147: FFmpex.execute/1
        (futurebits 0.1.0) lib/myapp/conversion.ex:67: Myapp.Conversion.convert_video/2

I’m new to this stack and not sure of where to start looking into this. Any suggestions? Thank you!

2

Hi Naja,
Could you post the command and code you use to obtain the error?

3

Yes, sorry. Here.

  def convert_video(file, conversions \\ 1) do
    output_path = "12345.mp4"
    command = FFmpex.new_command
      |> add_global_option(option_y())
      |> add_input_file(get_full_path(file))
      |> add_output_file(output_path)
      |> add_stream_specifier(stream_type: :video)
      |> add_stream_option(option_vcodec(Conf.converted_video_vcodec))
      |> add_stream_option(option_acodec(Conf.converted_video_acodec))
      |> add_stream_option(option_b(Conf.converted_video_vbitrate))
      |> add_file_option(option_bufsize(Conf.converted_video_buffer_size))
      |> add_file_option(option_max_muxing_queue_size(9999))
    :ok = execute(command)

Conf being a bunch of user-configurable strings. When I POST to this through automated testing on my local I can see the actual converted file, so it’s successful here. And when I try to prepare the command instead of execute it I get:

{"/usr/bin/ffmpeg", ["-y", "-i", "test/fixtures/large_test.mp4", "-max_muxing_queue_size", "9999", "-bufsize", "64K", "-b:v", "6K", "-acodec:v", "aac", "-vcodec:v", "libx264", "123456.mp4"]}

Thank you!

4

Have you tested what prepare returns on your server?

How does your Conf module work? The classic pitfall is using compile time configuration and trying to change it at runtime.