nixos/nzbget: add settings option

nixos/modules/services/misc/nzbget.nix

@@ -7,24 +7,12 @@ let
   pkg = pkgs.nzbget;
   stateDir = "/var/lib/nzbget";
   configFile = "${stateDir}/nzbget.conf";
-  configOpts = concatStringsSep " " (mapAttrsToList (name: value: "-o ${name}=${value}") nixosOpts);
-
-  nixosOpts = {
-    # allows nzbget to run as a "simple" service
-    OutputMode = "loggable";
-    # use journald for logging
-    WriteLog = "none";
-    ErrorTarget = "screen";
-    WarningTarget = "screen";
-    InfoTarget = "screen";
-    DetailTarget = "screen";
-    # required paths
-    ConfigTemplate = "${pkg}/share/nzbget/nzbget.conf";
-    WebDir = "${pkg}/share/nzbget/webui";
-    # nixos handles package updates
-    UpdateCheck = "none";
-  };
-
+  configOpts = concatStringsSep " " (mapAttrsToList (name: value: "-o ${name}=${escapeShellArg (toStr value)}") cfg.settings);
+  toStr = v:
+    if v == true then "yes"
+    else if v == false then "no"
+    else if isInt v then toString v
+    else v;
 in
 {
   imports = [
@@ -50,12 +38,41 @@ in
         default = "nzbget";
         description = "Group under which NZBGet runs";
       };
+
+      settings = mkOption {
+        type = with types; attrsOf (oneOf [ bool int str ]);
+        default = {};
+        description = ''
+          NZBGet configuration, passed via command line using switch -o. Refer to
+          <link xlink:href="https://github.com/nzbget/nzbget/blob/master/nzbget.conf"/>
+          for details on supported values.
+        '';
+        example = {
+          MainDir = "/data";
+        };
+      };
     };
   };
 
   # implementation
 
   config = mkIf cfg.enable {
+    services.nzbget.settings = {
+      # allows nzbget to run as a "simple" service
+      OutputMode = "loggable";
+      # use journald for logging
+      WriteLog = "none";
+      ErrorTarget = "screen";
+      WarningTarget = "screen";
+      InfoTarget = "screen";
+      DetailTarget = "screen";
+      # required paths
+      ConfigTemplate = "${pkg}/share/nzbget/nzbget.conf";
+      WebDir = "${pkg}/share/nzbget/webui";
+      # nixos handles package updates
+      UpdateCheck = "none";
+    };
+
     systemd.services.nzbget = {
       description = "NZBGet Daemon";
       after = [ "network.target" ];
@@ -64,6 +81,7 @@ in
         unrar
         p7zip
       ];
+
       preStart = ''
         if [ ! -f ${configFile} ]; then
           ${pkgs.coreutils}/bin/install -m 0700 ${pkg}/share/nzbget/nzbget.conf ${configFile}

nixos/tests/nzbget.nix

@@ -8,13 +8,21 @@ import ./make-test-python.nix ({ pkgs, ...} : {
     server = { ... }: {
       services.nzbget.enable = true;
 
+      # provide some test settings
+      services.nzbget.settings = {
+        "MainDir" = "/var/lib/nzbget";
+        "DirectRename" = true;
+        "DiskSpace" = 0;
+        "Server1.Name" = "this is a test";
+      };
+
       # hack, don't add (unfree) unrar to nzbget's path,
       # so we can run this test in CI
       systemd.services.nzbget.path = pkgs.lib.mkForce [ pkgs.p7zip ];
     };
   };
 
-  testScript = ''
+  testScript = { nodes, ... }: ''
     start_all()
 
     server.wait_for_unit("nzbget.service")
@@ -26,5 +34,13 @@ import ./make-test-python.nix ({ pkgs, ...} : {
     server.succeed(
         "${pkgs.nzbget}/bin/nzbget -n -o Control_iP=127.0.0.1 -o Control_port=6789 -o Control_password=tegbzn6789 -V"
     )
+
+    config = server.succeed("${nodes.server.config.systemd.services.nzbget.serviceConfig.ExecStart} --printconfig")
+
+    # confirm the test settings are applied
+    assert 'MainDir = "/var/lib/nzbget"' in config
+    assert 'DirectRename = "yes"' in config
+    assert 'DiskSpace = "0"' in config
+    assert 'Server1.Name = "this is a test"' in config
   '';
 })