nixos/deluge: support 2.x

nixos/modules/services/torrent/deluge.nix

@@ -5,6 +5,7 @@ with lib;
 let
   cfg = config.services.deluge;
   cfg_web = config.services.deluge.web;
+  isDeluge1 = versionOlder cfg.package.version "2.0.0";
 
   openFilesLimit = 4096;
   listenPortsDefault = [ 6881 6889 ];
@@ -18,11 +19,11 @@ let
   preStart = if cfg.declarative then ''
     if [ -e ${declarativeLockFile} ]; then
       # Was declarative before, no need to back up anything
-      ln -sf ${configFile} ${configDir}/core.conf
+      ${if isDeluge1 then "ln -sf" else "cp"} ${configFile} ${configDir}/core.conf
       ln -sf ${cfg.authFile} ${configDir}/auth
     else
       # Declarative for the first time, backup stateful files
-      ln -sb --suffix=.stateful ${configFile} ${configDir}/core.conf
+      ${if isDeluge1 then "ln -s" else "cp"} -b --suffix=.stateful ${configFile} ${configDir}/core.conf
       ln -sb --suffix=.stateful ${cfg.authFile} ${configDir}/auth
       echo "Autogenerated file that signifies that this server configuration is managed declaratively by NixOS" \
         > ${declarativeLockFile}
@@ -144,6 +145,14 @@ in {
             This always contains unzip, gnutar, xz, p7zip and bzip2.
           '';
         };
+
+        package = mkOption {
+          type = types.package;
+          example = literalExample "pkgs.deluge-1_x";
+          description = ''
+            Deluge package to use.
+          '';
+        };
       };
 
       deluge.web = {
@@ -170,6 +179,13 @@ in {
 
   config = mkIf cfg.enable {
 
+    services.deluge.package = mkDefault (
+      if versionAtLeast config.system.stateVersion "20.09" then
+        pkgs.deluge-2_x
+      else
+        pkgs.deluge-1_x
+    );
+
     # Provide a default set of `extraPackages`.
     services.deluge.extraPackages = with pkgs; [ unzip gnutar xz p7zip bzip2 ];
 
@@ -189,10 +205,10 @@ in {
       after = [ "network.target" ];
       description = "Deluge BitTorrent Daemon";
       wantedBy = [ "multi-user.target" ];
-      path = [ pkgs.deluge ] ++ cfg.extraPackages;
+      path = [ cfg.package ] ++ cfg.extraPackages;
       serviceConfig = {
         ExecStart = ''
-          ${pkgs.deluge}/bin/deluged \
+          ${cfg.package}/bin/deluged \
             --do-not-daemonize \
             --config ${configDir}
         '';
@@ -212,10 +228,11 @@ in {
       requires = [ "deluged.service" ];
       description = "Deluge BitTorrent WebUI";
       wantedBy = [ "multi-user.target" ];
-      path = [ pkgs.deluge ];
+      path = [ cfg.package ];
       serviceConfig = {
         ExecStart = ''
-          ${pkgs.deluge}/bin/deluge-web \
+          ${cfg.package}/bin/deluge-web \
+            ${optionalString (!isDeluge1) "--do-not-daemonize"} \
             --config ${configDir} \
             --port ${toString cfg.web.port}
         '';
@@ -234,7 +251,7 @@ in {
       })
     ];
 
-    environment.systemPackages = [ pkgs.deluge ];
+    environment.systemPackages = [ cfg.package ];
 
     users.users = mkIf (cfg.user == "deluge") {
       deluge = {