nix/dash.nix


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{ config, lib, pkgs, ... }:

with lib;
let
  cfg = config.services.brook;
in
{
  options.services.brook.dash = {
    enable = mkEnableOption "ffmpeg dash server";

    name = mkOption {
      type = types.str;
      description = ''
        The name of the rtmp endpoint of the stream.  This might show up as
        metadata in some clients
      '';
    };

    openFirewall = mkEnableOption "open firewall";
  };

  config = mkIf cfg.dash.enable {
    networking.firewall = mkIf cfg.dash.openFirewall {
      allowedTCPPorts = [ 1935 ];
      allowedUDPPorts = [ 1935 ];
    };

    systemd.services.brook-ffmpeg = {
      wantedBy = [ "multi-user.target" ];
      after = [ "network.target" ];
      
      serviceConfig = {
        StateDirectory = "dash";
        Group = "nginx";
      };
      
      script = let
        ffmpeg = "${pkgs.ffmpeg}/bin/ffmpeg";
      in
        ''
          while true; do
            ${ffmpeg} -listen 1 -i rtmp://0.0.0.0:1935/${cfg.dash.name}/live \
              -c:v libx264 -x264opts "keyint=24:min-keyint=24:no-scenecut" -r 24 \
              -c:a aac -b:a 128k \
              -bf 1 -b_strategy 0 -sc_threshold 0 -pix_fmt yuv420p \
              -map 0:v:0 -map 0:a:0 -map 0:v:0 \
              -map 0:a:0 -map 0:v:0 -map 0:a:0 \
              /var/lib/dash/live.mpd
          done
        '';
    };
  };
}