From ccee8dc09f791f363c1e4d2053983434aec54bc6 Mon Sep 17 00:00:00 2001
From: Doron Behar <doron.behar@gmail.com>
Date: Sun, 16 Aug 2020 17:56:49 +0300
Subject: nixos/mpd: Allow to configure a credentialsFile

Allow to specify a password file to be located outside the store, and be
read in `ExecStartPre`.
---
 nixos/modules/services/audio/mpd.nix | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

(limited to 'nixos/modules')

diff --git a/nixos/modules/services/audio/mpd.nix b/nixos/modules/services/audio/mpd.nix
index 1d2a982ac53..9e77ee85b89 100644
--- a/nixos/modules/services/audio/mpd.nix
+++ b/nixos/modules/services/audio/mpd.nix
@@ -140,6 +140,18 @@ in {
         '';
       };
 
+      credentialsFile = mkOption {
+        type = types.path;
+        description = ''
+          Path to a file to be merged with the settings during the service startup.
+          Useful to merge a file which is better kept out of the Nix store
+          because it contains sensible data like MPD's password. Example may look like this:
+          <literal>password "myMpdPassword@read,add,control,admin"</literal>
+        '';
+        default = "/dev/null";
+        example = "/var/lib/secrets/mpd.conf";
+      };
+
       fluidsynth = mkOption {
         type = types.bool;
         default = false;
@@ -181,7 +193,12 @@ in {
 
       serviceConfig = {
         User = "${cfg.user}";
-        ExecStart = "${pkgs.mpd}/bin/mpd --no-daemon ${mpdConf}";
+        ExecStart = "${pkgs.mpd}/bin/mpd --no-daemon /etc/mpd.conf";
+        ExecStartPre = pkgs.writeScript "mpd-start-pre" ''
+          #!${pkgs.runtimeShell}
+          set -euo pipefail
+          cat ${mpdConf} ${cfg.credentialsFile} > /etc/mpd.conf
+        '';
         Type = "notify";
         LimitRTPRIO = 50;
         LimitRTTIME = "infinity";
@@ -195,6 +212,14 @@ in {
         Restart = "always";
       };
     };
+    environment.etc."mpd.conf" = {
+      mode = "0640";
+      group = cfg.group;
+      user = cfg.user;
+      # To be modified by the service' ExecStartPre
+      text = ''
+      '';
+    };
 
     users.users = optionalAttrs (cfg.user == name) {
       ${name} = {
-- 
cgit 1.4.1


From b4756fe0c473f40f337c2c7d1059a5de5d47e181 Mon Sep 17 00:00:00 2001
From: Doron Behar <doron.behar@gmail.com>
Date: Thu, 10 Sep 2020 16:51:28 +0300
Subject: nixos/mpd: Mention in /etc/mpd.conf it was autogenerated

---
 nixos/modules/services/audio/mpd.nix | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'nixos/modules')

diff --git a/nixos/modules/services/audio/mpd.nix b/nixos/modules/services/audio/mpd.nix
index 9e77ee85b89..ba20b1b98d9 100644
--- a/nixos/modules/services/audio/mpd.nix
+++ b/nixos/modules/services/audio/mpd.nix
@@ -11,6 +11,10 @@ let
   cfg = config.services.mpd;
 
   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) ''
-- 
cgit 1.4.1