nzbget: Fix script for copying default config file template (#51235)

* nzbget: Fix configFile / dataDir checking in service script

* nzbget: improve the description for the `configFile` option

* nzbget: Add detail to the `configFile` option description

* nzbget: Improve wording of `configFile` option

* nzbget: Refactor dataDir management into systemd config

* nzbget: Remove debug

1 files changed, 19 insertions, 21 deletions

diff --git a/nixos/modules/services/misc/nzbget.nix b/nixos/modules/services/misc/nzbget.nix
index e24cecf2080..6ab98751c57 100644
--- a/nixos/modules/services/misc/nzbget.nix
+++ b/nixos/modules/services/misc/nzbget.nix
@@ -4,6 +4,7 @@ with lib;
 
 let
   cfg = config.services.nzbget;
+  dataDir = builtins.dirOf cfg.configFile;
 in {
   options = {
     services.nzbget = {
@@ -41,6 +42,12 @@ in {
         default = "nzbget";
         description = "Group under which NZBGet runs";
       };
+
+      configFile = mkOption {
+        type = types.str;
+        default = "/var/lib/nzbget/nzbget.conf";
+        description = "Path for NZBGet's config file. (If this doesn't exist, the default config template is copied here.)";
+      };
     };
   };
 
@@ -54,36 +61,25 @@ in {
         p7zip
       ];
       preStart = ''
-        datadir=${cfg.dataDir}
-        configfile=${cfg.dataDir}/nzbget.conf
         cfgtemplate=${cfg.package}/share/nzbget/nzbget.conf
-        test -d $datadir || {
-          echo "Creating nzbget data directory in $datadir"
-          mkdir -p $datadir
-        }
-        test -f $configfile || {
-          echo "nzbget.conf not found. Copying default config $cfgtemplate to $configfile"
-          cp $cfgtemplate $configfile
-          echo "Setting $configfile permissions to 0700 (needs to be written and contains plaintext credentials)"
-          chmod 0700 $configfile
+        if [ ! -f ${cfg.configFile} ]; then
+          echo "${cfg.configFile} not found. Copying default config $cfgtemplate to ${cfg.configFile}"
+          install -m 0700 $cfgtemplate ${cfg.configFile}
           echo "Setting temporary \$MAINDIR variable in default config required in order to allow nzbget to complete initial start"
           echo "Remember to change this to a proper value once NZBGet startup has been completed"
-          sed -i -e 's/MainDir=.*/MainDir=\/tmp/g' $configfile
-        }
-        echo "Ensuring proper ownership of $datadir (${cfg.user}:${cfg.group})."
-        chown -R ${cfg.user}:${cfg.group} $datadir
+          sed -i -e 's/MainDir=.*/MainDir=\/tmp/g' ${cfg.configFile}
+        fi
       '';
 
       script = ''
-        configfile=${cfg.dataDir}/nzbget.conf
-        args="--daemon --configfile $configfile"
-        # The script in preStart (above) copies nzbget's config template to datadir on first run, containing paths that point to the nzbget derivation installed at the time. 
-        # These paths break when nzbget is upgraded & the original derivation is garbage collected. If such broken paths are found in the config file, override them to point to 
+        args="--daemon --configfile ${cfg.configFile}"
+        # The script in preStart (above) copies nzbget's config template to datadir on first run, containing paths that point to the nzbget derivation installed at the time.
+        # These paths break when nzbget is upgraded & the original derivation is garbage collected. If such broken paths are found in the config file, override them to point to
         # the currently installed nzbget derivation.
         cfgfallback () {
-          local hit=`grep -Po "(?<=^$1=).*+" "$configfile" | sed 's/[ \t]*$//'` # Strip trailing whitespace
+          local hit=`grep -Po "(?<=^$1=).*+" "${cfg.configFile}" | sed 's/[ \t]*$//'` # Strip trailing whitespace
           ( test $hit && test -e $hit ) || {
-            echo "In $configfile, valid $1 not found; falling back to $1=$2"
+            echo "In ${cfg.configFile}, valid $1 not found; falling back to $1=$2"
             args+=" -o $1=$2"
           }
         }
@@ -93,6 +89,8 @@ in {
       '';
 
       serviceConfig = {
+        StateDirectory = dataDir;
+        StateDirectoryMode = "0700";
         Type = "forking";
         User = cfg.user;
         Group = cfg.group;