hit_rate

hit_rate.exs

defmodule HitRate do
  @moduledoc """
  Documentation for `HitRate`.
  """

  def calc(file_path) do
    file_path
    |> stream()
    |> Enum.to_list()
    |> IO.inspect(label: :stream)
    |> acc_on_video_id()
    |> print()
  end

  defp stream(file_path) do
    File.stream!(file_path)
    |> Stream.map(&parse_line/1)
    |> Stream.filter(fn
      {_, _} ->
        true

      _ ->
        false
    end)
  end

  # Fields: timestamp time-taken c-ip filesize s-ip s-port sc-status sc-bytes cs-method cs-uri-stem - rs-duration rs-bytes c-referrer c-user-agent customer-id x-ec_custom-1
  # 1523756544 3 86.45.165.83 1845784 152.195.141.240 80 TCP_HIT/200 1846031 GET http://c13.adrise.tv/04C0BF/v2/sources/content-owners/sgl-entertainment/275211/v0401185814-1389k.mp4+740005.ts - 0 486 "-" "TubiExoPlayer/2.12.9 (Linux;Android 6.0) ExoPlayerLib/2.4.2" 49343 "-" 
  defp parse_line(line) do
    case line |> String.split(~r/\s+/) do
      [_, _, _, _, _, _, sc_status, _, _, url | _] ->
        case video_id(url) do
          :error ->
            :error

          id ->
            case sc_status do
              "TCP_HIT" <> _ ->
                {id, true}

              _ ->
                {id, false}
            end
        end

      _ ->
        :error
    end
  end

  # http://c13.adrise.tv/04C0BF/v2/sources/content-owners/sgl-entertainment/275211/v0401185814-1389k.mp4+740005.ts
  defp video_id(url) do
    case Regex.run(~r{/(\d+)/[^/]+$}, url) |> IO.inspect(label: url) do
      [_, id] ->
        id

      _ ->
        :error
    end
  end

  defp acc_on_video_id(stream) do
    Enum.reduce(stream, %{}, fn
      %{video_id: id, hit?: true}, acc ->
        case acc do
          %{^id => {hit_count, _}} ->
            %{acc | hit_count: hit_count + 1}

          %{} ->
            Map.put_new(acc, id, {1, 0})
        end

      %{video_id: id, hit?: false}, acc ->
        case acc do
          %{^id => {_, miss_count}} ->
            %{acc | hit_count: miss_count + 1}

          %{} ->
            Map.put_new(acc, id, {0, 1})
        end
    end)
  end

  defp print(result) do
    IO.inspect(result, limit: :infinte)
  end

  def run do
    "access.log" |> calc()
  end
end