port_runner.ex

defmodule PortRunner do
  use GenServer, restart: :temporary

  defmodule State do
    defstruct [:command, :exit_status, :port, arguments: []]
  end

  @spec start_link(State.t() | map() | keyword()) :: GenServer.on_start()
  def start_link(args) do
    GenServer.start_link(__MODULE__, args)
  end

  def init(args) do
    state =
      State
      |> struct!(args)

    {:ok, state, {:continue, :run_command}}
  end

  def handle_continue(
        :run_command,
        %{
          command: command,
          arguments: arguments
        } = state
      ) do
    port =
      Port.open({:spawn_executable, command}, [
        :binary,
        :use_stdio,
        :exit_status,
        :stderr_to_stdout,
        {:line, 255},
        args: arguments
      ])

    {:noreply, %{state | port: port}}
  end

  def handle_info({port, {:data, data}}, %{port: port} = state) do
    IO.inspect({:data, data},
      label: "HANDLE_INFO_DATA >>>>>>>>>>>>>>",
      limit: :infinity
    )

    {:noreply, state}
  end

  def handle_info({port, {:exit_status, code}}, %{port: port} = state) do
    IO.inspect({:exit_status, code},
      label: "HANDLE_INFO_EXIT >>>>>>>>>>>>>>",
      limit: :infinity
    )

    {:noreply, %{state | exit_status: code}}
  end

  def handle_info(msg, state) do
    IO.inspect(msg, label: "HANDLE_INFO_ANY >>>>>>>>>>>>>>", limit: :infinity)
    {:noreply, state}
  end
end

test_base =
  Path.join([
    File.cwd!(),
    "apps",
    "manager",
    "test",
    "fixtures",
    "videos",
    "baseline.mp4"
  ])

test_diff =
  Path.join([
    File.cwd!(),
    "apps",
    "manager",
    "test",
    "fixtures",
    "videos",
    "different_FAIL.mp4"
  ])

PortRunner.start_link(
  command: System.find_executable("ffmpeg"),
  arguments: [
    "-i",
    test_base,
    "-i",
    test_diff,
    "-filter_complex",
    "blend=all_mode=difference,hue=s=0,blackdetect=pic_th=0.85",
    "-f",
    "NULL",
    "-"
  ]
)

test_same =
  Path.join([
    File.cwd!(),
    "apps",
    "manager",
    "test",
    "fixtures",
    "videos",
    "same_PASS.mp4"
  ])

PortRunner.start_link(
  command: System.find_executable("ffmpeg"),
  arguments: [
    "-i",
    test_base,
    "-i",
    test_same,
    "-filter_complex",
    "blend=all_mode=difference,hue=s=0,blackdetect=pic_th=0.85",
    "-f",
    "NULL",
    "-"
  ]
)

PortRunner.start_link(
  command: System.find_executable("ruby"),
  arguments: ["-e", "puts 'hello'; $stdout.flush; puts 'world'; $stdout.flush; puts 'break\nline'"]
)

PortRunner.start_link(
  command: System.find_executable("ruby"),
  arguments: ["-e", "puts 'hello'; $stdout.flush; sleep(1); puts 'world'; $stdout.flush; puts 'break\nline'"]
)

PortRunner.start_link(
  command: System.find_executable("ruby"),
  arguments: ["-e", "puts 'hello'; puts 'world'; puts 'break\nline'"]
)

PortRunner.start_link(
  command: System.find_executable("ruby"),
  arguments: ["-e", "puts 'h'*600; puts 'world'; puts 'break\nline'"]
)