nixos: Add working directory config option to quickpeepSearch

nixos_modules/quickpeepSearch.nix

@@ -49,6 +49,14 @@ with lib;
         '';
       };
 
+      workingDir = mkOption {
+        type = with types; path;
+        description = ''
+          Path to a working directory to run the web interface and indexer from.
+          This is the base from which paths in the config file are looked up from.
+        '';
+      };
+
       autoIndexUrl = mkOption {
         default = null;
         type = with types; nullOr str;
@@ -80,6 +88,7 @@ with lib;
         Type = "simple";
         User = "${cfg.user}";
         ExecStart = ''${quickpeep}/bin/quickpeep ${cfg.bindHost}:${builtins.toString cfg.bindPort}'';
+        WorkingDirectory = cfg.workingDir;
       };
     };
 
@@ -90,6 +99,7 @@ with lib;
         Type = "simple";
         User = "${cfg.user}";
         ExecStart = ''${quickpeep}/bin/qp-indexer --config ${lib.strings.escapeShellArg cfg.configPath} --feed ${lib.strings.escapeShellArg cfg.autoIndexUrl}'';
+        WorkingDirectory = cfg.workingDir;
       };
     };