nixos/mpdscribble: init

nixos/modules/module-list.nix

@@ -226,6 +226,7 @@
   ./services/audio/icecast.nix
   ./services/audio/liquidsoap.nix
   ./services/audio/mpd.nix
+  ./services/audio/mpdscribble.nix
   ./services/audio/mopidy.nix
   ./services/audio/roon-server.nix
   ./services/audio/slimserver.nix

nixos/modules/services/audio/mpdscribble.nix

@@ -0,0 +1,202 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.mpdscribble;
+  mpdCfg = config.services.mpd;
+
+  endpointUrls = {
+    "last.fm" = "http://post.audioscrobbler.com";
+    "libre.fm" = "http://turtle.libre.fm";
+    "jamendo" = "http://postaudioscrobbler.jamendo.com";
+    "listenbrainz" = "http://proxy.listenbrainz.org";
+  };
+
+  mkSection = secname: secCfg: ''
+    [${secname}]
+    url      = ${secCfg.url}
+    username = ${secCfg.username}
+    password = {{${secname}_PASSWORD}}
+    journal  = /var/lib/mpdscribble/${secname}.journal
+  '';
+
+  endpoints = concatStringsSep "\n" (mapAttrsToList mkSection cfg.endpoints);
+  cfgTemplate = pkgs.writeText "mpdscribble.conf" ''
+    ## This file was automatically genenrated by NixOS and will be overwritten.
+    ## Do not edit. Edit your NixOS configuration instead.
+
+    ## mpdscribble - an audioscrobbler for the Music Player Daemon.
+    ## http://mpd.wikia.com/wiki/Client:mpdscribble
+
+    # HTTP proxy URL.
+    ${optionalString (cfg.proxy != null) "proxy = ${cfg.proxy}"}
+
+    # The location of the mpdscribble log file.  The special value
+    # "syslog" makes mpdscribble use the local syslog daemon.  On most
+    # systems, log messages will appear in /var/log/daemon.log then.
+    # "-" means log to stderr (the current terminal).
+    log = -
+
+    # How verbose mpdscribble's logging should be.  Default is 1.
+    verbose = ${toString cfg.verbose}
+
+    # How often should mpdscribble save the journal file? [seconds]
+    journal_interval = ${toString cfg.journalInterval}
+
+    # The host running MPD, possibly protected by a password
+    # ([PASSWORD@]HOSTNAME).
+    host = ${(optionalString (cfg.passwordFile != null) "{{MPD_PASSWORD}}@") + cfg.host}
+
+    # The port that the MPD listens on and mpdscribble should try to
+    # connect to.
+    port = ${toString cfg.port}
+
+    ${endpoints}
+  '';
+
+  cfgFile = "/run/mpdscribble/mpdscribble.conf";
+
+  replaceSecret = secretFile: placeholder: targetFile:
+    optionalString (secretFile != null) ''
+      ${pkgs.replace}/bin/replace-literal -ef ${placeholder} "$(cat ${secretFile})" ${targetFile}'';
+
+  preStart = pkgs.writeShellScript "mpdscribble-pre-start" ''
+    cp -f "${cfgTemplate}" "${cfgFile}"
+    ${replaceSecret cfg.passwordFile "{{MPD_PASSWORD}}" cfgFile}
+    ${concatStringsSep "\n" (mapAttrsToList (secname: cfg:
+      replaceSecret cfg.passwordFile "{{${secname}_PASSWORD}}" cfgFile)
+      cfg.endpoints)}
+  '';
+
+  localMpd = (cfg.host == "localhost" || cfg.host == "127.0.0.1");
+
+in {
+  ###### interface
+
+  options.services.mpdscribble = {
+
+    enable = mkEnableOption "mpdscribble";
+
+    proxy = mkOption {
+      default = null;
+      type = types.nullOr types.str;
+      description = ''
+        HTTP proxy URL.
+      '';
+    };
+
+    verbose = mkOption {
+      default = 1;
+      type = types.int;
+      description = ''
+        Log level for the mpdscribble daemon.
+      '';
+    };
+
+    journalInterval = mkOption {
+      default = 600;
+      example = 60;
+      type = types.int;
+      description = ''
+        How often should mpdscribble save the journal file? [seconds]
+      '';
+    };
+
+    host = mkOption {
+      default = (if mpdCfg.network.listenAddress != "any" then
+        mpdCfg.network.listenAddress
+      else
+        "localhost");
+      type = types.str;
+      description = ''
+        Host for the mpdscribble daemon to search for a mpd daemon on.
+      '';
+    };
+
+    passwordFile = mkOption {
+      default = if localMpd then
+        (findFirst
+          (c: any (x: x == "read") c.permissions)
+          { passwordFile = null; }
+          mpdCfg.credentials).passwordFile
+      else
+        null;
+      type = types.nullOr types.str;
+      description = ''
+        File containing the password for the mpd daemon.
+        If there is a local mpd configured using <option>services.mpd.credentials</option>
+        the default is automatically set to a matching passwordFile of the local mpd.
+      '';
+    };
+
+    port = mkOption {
+      default = mpdCfg.network.port;
+      type = types.port;
+      description = ''
+        Port for the mpdscribble daemon to search for a mpd daemon on.
+      '';
+    };
+
+    endpoints = mkOption {
+      type = (let
+        endpoint = { name, ... }: {
+          options = {
+            url = mkOption {
+              type = types.str;
+              default = endpointUrls.${name} or "";
+              description =
+                "The url endpoint where the scrobble API is listening.";
+            };
+            username = mkOption {
+              type = types.str;
+              description = ''
+                Username for the scrobble service.
+              '';
+            };
+            passwordFile = mkOption {
+              type = types.nullOr types.str;
+              description =
+                "File containing the password, either as MD5SUM or cleartext.";
+            };
+          };
+        };
+      in types.attrsOf (types.submodule endpoint));
+      default = { };
+      example = {
+        "last.fm" = {
+          username = "foo";
+          passwordFile = "/run/secrets/lastfm_password";
+        };
+      };
+      description = ''
+        Endpoints to scrobble to.
+        If the endpoint is one of "${
+          concatStringsSep "\", \"" (attrNames endpointUrls)
+        }" the url is set automatically.
+      '';
+    };
+
+  };
+
+  ###### implementation
+
+  config = mkIf cfg.enable {
+    systemd.services.mpdscribble = {
+      after = [ "network.target" ] ++ (optional localMpd "mpd.service");
+      description = "mpdscribble mpd scrobble client";
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = {
+        DynamicUser = true;
+        StateDirectory = "mpdscribble";
+        RuntimeDirectory = "mpdscribble";
+        RuntimeDirectoryMode = "700";
+        # TODO use LoadCredential= instead of running preStart with full privileges?
+        ExecStartPre = "+${preStart}";
+        ExecStart =
+          "${pkgs.mpdscribble}/bin/mpdscribble --no-daemon --conf ${cfgFile}";
+      };
+    };
+  };
+
+}