nixpkgs/nixos/tests/mpd.nix

import ./make-test-python.nix ({ pkgs, lib, ... }:
  let
    track = pkgs.fetchurl {
      # Sourced from http://freemusicarchive.org/music/Blue_Wave_Theory/Surf_Music_Month_Challenge/Skyhawk_Beach_fade_in
      # License: http://creativecommons.org/licenses/by-sa/4.0/

      name = "Blue_Wave_Theory-Skyhawk_Beach.mp3";
      url = https://freemusicarchive.org/file/music/ccCommunity/Blue_Wave_Theory/Surf_Music_Month_Challenge/Blue_Wave_Theory_-_04_-_Skyhawk_Beach.mp3;
      sha256 = "0xw417bxkx4gqqy139bb21yldi37xx8xjfxrwaqa0gyw19dl6mgp";
    };

    defaultCfg = rec {
      user = "mpd";
      group = "mpd";
      dataDir = "/var/lib/mpd";
      musicDirectory = "${dataDir}/music";
    };

    defaultMpdCfg = with defaultCfg; {
      inherit dataDir musicDirectory user group;
      enable = true;
    };

    musicService = { user, group, musicDirectory }: {
      description = "Sets up the music file(s) for MPD to use.";
      requires = [ "mpd.service" ];
      after = [ "mpd.service" ];
      wantedBy = [ "default.target" ];
      script = ''
        mkdir -p ${musicDirectory} && chown -R ${user}:${group} ${musicDirectory}
        cp ${track} ${musicDirectory}
        chown ${user}:${group} ${musicDirectory}/$(basename ${track})
      '';
    };

    mkServer = { mpd, musicService, }:
      { boot.kernelModules = [ "snd-dummy" ];
        sound.enable = true;
        services.mpd = mpd;
        systemd.services.musicService = musicService;
      };
  in {
    name = "mpd";
    meta = with pkgs.stdenv.lib.maintainers; {
      maintainers = [ emmanuelrosa ];
    };

  nodes =
    { client =
      { ... }: { };

      serverALSA =
        { ... }: lib.mkMerge [
          (mkServer {
            mpd = defaultMpdCfg // {
              network.listenAddress = "any";
              extraConfig = ''
                audio_output {
                  type "alsa"
                  name "ALSA"
                  mixer_type "null"
                }
              '';
            };
            musicService = with defaultMpdCfg; musicService { inherit user group musicDirectory; };
          })
          { networking.firewall.allowedTCPPorts = [ 6600 ]; }
        ];

      serverPulseAudio =
        { ... }: lib.mkMerge [
          (mkServer {
            mpd = defaultMpdCfg // {
              extraConfig = ''
                audio_output {
                  type "pulse"
                  name "The Pulse"
                }
              '';
            };

            musicService = with defaultCfg; musicService { inherit user group musicDirectory; };
          })
          {
            hardware.pulseaudio = {
              enable = true;
              systemWide = true;
              tcp.enable = true;
              tcp.anonymousClients.allowAll = true;
            };
            systemd.services.mpd.environment.PULSE_SERVER = "localhost";
          }
        ];
    };

  testScript = ''
    mpc = "${pkgs.mpc_cli}/bin/mpc --wait"

    # Connects to the given server and attempts to play a tune.
    def play_some_music(server):
        server.wait_for_unit("mpd.service")
        server.succeed(f"{mpc} update")
        _, tracks = server.execute(f"{mpc} ls")

        for track in tracks.splitlines():
            server.succeed(f"{mpc} add {track}")

        _, added_tracks = server.execute(f"{mpc} listall")

        # Check we succeeded adding audio tracks to the playlist
        assert len(added_tracks.splitlines()) > 0

        server.succeed(f"{mpc} play")

        _, output = server.execute(f"{mpc} status")
        # Assure audio track is playing
        assert "playing" in output

        server.succeed(f"{mpc} stop")


    play_some_music(serverALSA)
    play_some_music(serverPulseAudio)

    client.wait_for_unit("multi-user.target")
    client.succeed(f"{mpc} -h serverALSA status")

    # The PulseAudio-based server is configured not to accept external client connections
    # to perform the following test:
    client.fail(f"{mpc} -h serverPulseAudio status")
  '';
})