summary refs log tree commit diff
path: root/nixos/modules/services/audio/mpd.nix
blob: eee6c5f423d5d0fd29d013bb036e081038ca693a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
{ config, lib, pkgs, ... }:

with lib;

let

  name = "mpd";

  uid = config.ids.uids.mpd;
  gid = config.ids.gids.mpd;
  cfg = config.services.mpd;

  credentialsPlaceholder = (creds:
    let
      placeholders = (imap0
        (i: c: ''password "{{password-${toString i}}}@${concatStringsSep "," c.permissions}"'')
        creds);
    in
      concatStringsSep "\n" placeholders);

  mpdConf = pkgs.writeText "mpd.conf" ''
    # This file was automatically generated by NixOS. Edit mpd's configuration
    # via NixOS' configuration.nix, as this file will be rewritten upon mpd's
    # restart.

    music_directory     "${cfg.musicDirectory}"
    playlist_directory  "${cfg.playlistDirectory}"
    ${lib.optionalString (cfg.dbFile != null) ''
      db_file             "${cfg.dbFile}"
    ''}
    state_file          "${cfg.dataDir}/state"
    sticker_file        "${cfg.dataDir}/sticker.sql"

    ${optionalString (cfg.network.listenAddress != "any") ''bind_to_address "${cfg.network.listenAddress}"''}
    ${optionalString (cfg.network.port != 6600)  ''port "${toString cfg.network.port}"''}
    ${optionalString (cfg.fluidsynth) ''
      decoder {
              plugin "fluidsynth"
              soundfont "${pkgs.soundfont-fluid}/share/soundfonts/FluidR3_GM2-2.sf2"
      }
    ''}

    ${optionalString (cfg.credentials != []) (credentialsPlaceholder cfg.credentials)}

    ${cfg.extraConfig}
  '';

in {

  ###### interface

  options = {

    services.mpd = {

      enable = mkOption {
        type = types.bool;
        default = false;
        description = ''
          Whether to enable MPD, the music player daemon.
        '';
      };

      startWhenNeeded = mkOption {
        type = types.bool;
        default = false;
        description = ''
          If set, <command>mpd</command> is socket-activated; that
          is, instead of having it permanently running as a daemon,
          systemd will start it on the first incoming connection.
        '';
      };

      musicDirectory = mkOption {
        type = with types; either path (strMatching "(http|https|nfs|smb)://.+");
        default = "${cfg.dataDir}/music";
        defaultText = "\${dataDir}/music";
        description = ''
          The directory or NFS/SMB network share where MPD reads music from. If left
          as the default value this directory will automatically be created before
          the MPD server starts, otherwise the sysadmin is responsible for ensuring
          the directory exists with appropriate ownership and permissions.
        '';
      };

      playlistDirectory = mkOption {
        type = types.path;
        default = "${cfg.dataDir}/playlists";
        defaultText = "\${dataDir}/playlists";
        description = ''
          The directory where MPD stores playlists. If left as the default value
          this directory will automatically be created before the MPD server starts,
          otherwise the sysadmin is responsible for ensuring the directory exists
          with appropriate ownership and permissions.
        '';
      };

      extraConfig = mkOption {
        type = types.lines;
        default = "";
        description = ''
          Extra directives added to to the end of MPD's configuration file,
          mpd.conf. Basic configuration like file location and uid/gid
          is added automatically to the beginning of the file. For available
          options see <literal>man 5 mpd.conf</literal>'.
        '';
      };

      dataDir = mkOption {
        type = types.path;
        default = "/var/lib/${name}";
        description = ''
          The directory where MPD stores its state, tag cache, playlists etc. If
          left as the default value this directory will automatically be created
          before the MPD server starts, otherwise the sysadmin is responsible for
          ensuring the directory exists with appropriate ownership and permissions.
        '';
      };

      user = mkOption {
        type = types.str;
        default = name;
        description = "User account under which MPD runs.";
      };

      group = mkOption {
        type = types.str;
        default = name;
        description = "Group account under which MPD runs.";
      };

      network = {

        listenAddress = mkOption {
          type = types.str;
          default = "127.0.0.1";
          example = "any";
          description = ''
            The address for the daemon to listen on.
            Use <literal>any</literal> to listen on all addresses.
          '';
        };

        port = mkOption {
          type = types.int;
          default = 6600;
          description = ''
            This setting is the TCP port that is desired for the daemon to get assigned
            to.
          '';
        };

      };

      dbFile = mkOption {
        type = types.nullOr types.str;
        default = "${cfg.dataDir}/tag_cache";
        defaultText = "\${dataDir}/tag_cache";
        description = ''
          The path to MPD's database. If set to <literal>null</literal> the
          parameter is omitted from the configuration.
        '';
      };

      credentials = mkOption {
        type = types.listOf (types.submodule {
          options = {
            passwordFile = mkOption {
              type = types.path;
              description = ''
                Path to file containing the password.
              '';
            };
            permissions = let
              perms = ["read" "add" "control" "admin"];
            in mkOption {
              type = types.listOf (types.enum perms);
              default = [ "read" ];
              description = ''
                List of permissions that are granted with this password.
                Permissions can be "${concatStringsSep "\", \"" perms}".
              '';
            };
          };
        });
        description = ''
          Credentials and permissions for accessing the mpd server.
        '';
        default = [];
        example = [
          {passwordFile = "/var/lib/secrets/mpd_readonly_password"; permissions = [ "read" ];}
          {passwordFile = "/var/lib/secrets/mpd_admin_password"; permissions = ["read" "add" "control" "admin"];}
        ];
      };

      fluidsynth = mkOption {
        type = types.bool;
        default = false;
        description = ''
          If set, add fluidsynth soundfont and configure the plugin.
        '';
      };
    };

  };


  ###### implementation

  config = mkIf cfg.enable {

    systemd.sockets.mpd = mkIf cfg.startWhenNeeded {
      description = "Music Player Daemon Socket";
      wantedBy = [ "sockets.target" ];
      listenStreams = [
        (if pkgs.lib.hasPrefix "/" cfg.network.listenAddress
          then cfg.network.listenAddress
          else "${optionalString (cfg.network.listenAddress != "any") "${cfg.network.listenAddress}:"}${toString cfg.network.port}")
      ];
      socketConfig = {
        Backlog = 5;
        KeepAlive = true;
        PassCredentials = true;
      };
    };

    systemd.services.mpd = {
      after = [ "network.target" "sound.target" ];
      description = "Music Player Daemon";
      wantedBy = optional (!cfg.startWhenNeeded) "multi-user.target";

      serviceConfig = mkMerge [
        {
          User = "${cfg.user}";
          ExecStart = "${pkgs.mpd}/bin/mpd --no-daemon /run/mpd/mpd.conf";
          ExecStartPre = pkgs.writeShellScript "mpd-start-pre" ''
            set -euo pipefail
            install -m 600 ${mpdConf} /run/mpd/mpd.conf
            ${optionalString (cfg.credentials != [])
            "${pkgs.replace}/bin/replace-literal -fe ${
              concatStringsSep " -a " (imap0 (i: c: "\"{{password-${toString i}}}\" \"$(cat ${c.passwordFile})\"") cfg.credentials)
            } /run/mpd/mpd.conf"}
          '';
          RuntimeDirectory = "mpd";
          Type = "notify";
          LimitRTPRIO = 50;
          LimitRTTIME = "infinity";
          ProtectSystem = true;
          NoNewPrivileges = true;
          ProtectKernelTunables = true;
          ProtectControlGroups = true;
          ProtectKernelModules = true;
          RestrictAddressFamilies = "AF_INET AF_INET6 AF_UNIX AF_NETLINK";
          RestrictNamespaces = true;
          Restart = "always";
        }
        (mkIf (cfg.dataDir == "/var/lib/${name}") {
          StateDirectory = [ name ];
        })
        (mkIf (cfg.playlistDirectory == "/var/lib/${name}/playlists") {
          StateDirectory = [ name "${name}/playlists" ];
        })
        (mkIf (cfg.musicDirectory == "/var/lib/${name}/music") {
          StateDirectory = [ name "${name}/music" ];
        })
      ];
    };

    users.users = optionalAttrs (cfg.user == name) {
      ${name} = {
        inherit uid;
        group = cfg.group;
        extraGroups = [ "audio" ];
        description = "Music Player Daemon user";
        home = "${cfg.dataDir}";
      };
    };

    users.groups = optionalAttrs (cfg.group == name) {
      ${name}.gid = gid;
    };
  };

}