{ config, lib, pkgs, ... }: let name = "mpd"; uid = config.ids.uids.mpd; gid = config.ids.gids.mpd; cfg = config.services.mpd; credentialsPlaceholder = (creds: let placeholders = (lib.imap0 (i: c: ''password "{{password-${toString i}}}@${lib.concatStringsSep "," c.permissions}"'') creds); in lib.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" ${lib.optionalString (cfg.network.listenAddress != "any") ''bind_to_address "${cfg.network.listenAddress}"''} ${lib.optionalString (cfg.network.port != 6600) ''port "${toString cfg.network.port}"''} ${lib.optionalString (cfg.fluidsynth) '' decoder { plugin "fluidsynth" soundfont "${pkgs.soundfont-fluid}/share/soundfonts/FluidR3_GM2-2.sf2" } ''} ${lib.optionalString (cfg.credentials != []) (credentialsPlaceholder cfg.credentials)} ${cfg.extraConfig} ''; in { ###### interface options = { services.mpd = { enable = lib.mkOption { type = lib.types.bool; default = false; description = '' Whether to enable MPD, the music player daemon. ''; }; startWhenNeeded = lib.mkOption { type = lib.types.bool; default = false; description = '' If set, {command}`mpd` is socket-activated; that is, instead of having it permanently running as a daemon, systemd will start it on the first incoming connection. ''; }; musicDirectory = lib.mkOption { type = with lib.types; either path (strMatching "(http|https|nfs|smb)://.+"); default = "${cfg.dataDir}/music"; defaultText = lib.literalExpression ''"''${dataDir}/music"''; description = '' The directory or NFS/SMB network share where MPD reads music from. If left as the default value this directory will automatically be created before the MPD server starts, otherwise the sysadmin is responsible for ensuring the directory exists with appropriate ownership and permissions. ''; }; playlistDirectory = lib.mkOption { type = lib.types.path; default = "${cfg.dataDir}/playlists"; defaultText = lib.literalExpression ''"''${dataDir}/playlists"''; description = '' The directory where MPD stores playlists. If left as the default value this directory will automatically be created before the MPD server starts, otherwise the sysadmin is responsible for ensuring the directory exists with appropriate ownership and permissions. ''; }; extraConfig = lib.mkOption { type = lib.types.lines; default = ""; description = '' Extra directives added to to the end of MPD's configuration file, mpd.conf. Basic configuration like file location and uid/gid is added automatically to the beginning of the file. For available options see {manpage}`mpd.conf(5)`. ''; }; dataDir = lib.mkOption { type = lib.types.path; default = "/var/lib/${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 = lib.mkOption { type = lib.types.str; default = name; description = "User account under which MPD runs."; }; group = lib.mkOption { type = lib.types.str; default = name; description = "Group account under which MPD runs."; }; network = { listenAddress = lib.mkOption { type = lib.types.str; default = "127.0.0.1"; example = "any"; description = '' The address for the daemon to listen on. Use `any` to listen on all addresses. ''; }; port = lib.mkOption { type = lib.types.port; default = 6600; description = '' This setting is the TCP port that is desired for the daemon to get assigned to. ''; }; }; dbFile = lib.mkOption { type = lib.types.nullOr lib.types.str; default = "${cfg.dataDir}/tag_cache"; defaultText = lib.literalExpression ''"''${dataDir}/tag_cache"''; description = '' The path to MPD's database. If set to `null` the parameter is omitted from the configuration. ''; }; credentials = lib.mkOption { type = lib.types.listOf (lib.types.submodule { options = { passwordFile = lib.mkOption { type = lib.types.path; description = '' Path to file containing the password. ''; }; permissions = let perms = ["read" "add" "control" "admin"]; in lib.mkOption { type = lib.types.listOf (lib.types.enum perms); default = [ "read" ]; description = '' List of permissions that are granted with this password. Permissions can be "${lib.concatStringsSep "\", \"" perms}". ''; }; }; }); description = '' Credentials and permissions for accessing the mpd server. ''; default = []; example = [ {passwordFile = "/var/lib/secrets/mpd_readonly_password"; permissions = [ "read" ];} {passwordFile = "/var/lib/secrets/mpd_admin_password"; permissions = ["read" "add" "control" "admin"];} ]; }; fluidsynth = lib.mkOption { type = lib.types.bool; default = false; description = '' If set, add fluidsynth soundfont and configure the plugin. ''; }; }; }; ###### implementation config = lib.mkIf cfg.enable { # install mpd units systemd.packages = [ pkgs.mpd ]; systemd.sockets.mpd = lib.mkIf cfg.startWhenNeeded { wantedBy = [ "sockets.target" ]; listenStreams = [ "" # Note: this is needed to override the upstream unit (if pkgs.lib.hasPrefix "/" cfg.network.listenAddress then cfg.network.listenAddress else "${lib.optionalString (cfg.network.listenAddress != "any") "${cfg.network.listenAddress}:"}${toString cfg.network.port}") ]; }; systemd.services.mpd = { wantedBy = lib.optional (!cfg.startWhenNeeded) "multi-user.target"; preStart = '' set -euo pipefail install -m 600 ${mpdConf} /run/mpd/mpd.conf '' + lib.optionalString (cfg.credentials != []) (lib.concatStringsSep "\n" (lib.imap0 (i: c: ''${pkgs.replace-secret}/bin/replace-secret '{{password-${toString i}}}' '${c.passwordFile}' /run/mpd/mpd.conf'') cfg.credentials)); serviceConfig = { User = "${cfg.user}"; # Note: the first "" overrides the ExecStart from the upstream unit ExecStart = [ "" "${pkgs.mpd}/bin/mpd --systemd /run/mpd/mpd.conf" ]; RuntimeDirectory = "mpd"; StateDirectory = [] ++ lib.optionals (cfg.dataDir == "/var/lib/${name}") [ name ] ++ lib.optionals (cfg.playlistDirectory == "/var/lib/${name}/playlists") [ name "${name}/playlists" ] ++ lib.optionals (cfg.musicDirectory == "/var/lib/${name}/music") [ name "${name}/music" ]; }; }; users.users = lib.optionalAttrs (cfg.user == name) { ${name} = { inherit uid; group = cfg.group; extraGroups = [ "audio" ]; description = "Music Player Daemon user"; home = "${cfg.dataDir}"; }; }; users.groups = lib.optionalAttrs (cfg.group == name) { ${name}.gid = gid; }; }; }