feat(nixos): add copyparty opds volume

configs/nixos/AGENTS.md

@@ -57,5 +57,7 @@
   Use a sudo `nix-store --import` path for unsigned deploy closures.
 - Public DNS entries are not managed through the NixOS configuration.
   Do not describe NixOS route choices as public-DNS management.
+- The pinned `copyparty-min` package includes Copyparty's OPDS support.
+  Enable OPDS with the `opds` volume flag or global Copyparty option; do not assume the minimal package removes it.
 - Do not hand-author `hardware-configuration.nix` for a host that has not been generated on that machine.
   Generate it on the target system or live ISO, then stage it before evaluating the flake.

configs/nixos/guests/copyparty.nix

@@ -6,6 +6,14 @@
 let
   cfg = config.guests.copyparty;
 
+  rootVolume = cfg.volumes."/" or null;
+
+  rootPlaceholderRules = lib.optionals (rootVolume != null) (
+    lib.mapAttrsToList (urlPath: _volume: "d ${rootVolume.hostPath}${urlPath} 2770 root storage - -") (
+      lib.filterAttrs (urlPath: _volume: urlPath != "/" && lib.hasPrefix "/" urlPath) cfg.volumes
+    )
+  );
+
   volumeType = lib.types.submodule {
     options = {
       hostPath = lib.mkOption {
@@ -99,6 +107,8 @@ in
       href = lib.mkIf cfg.reverseProxy.enable "https://${cfg.reverseProxy.route.domain}/?h";
     };
 
+    systemd.tmpfiles.rules = rootPlaceholderRules;
+
     guests.copyparty = {
       interior.modules.services.copyparty = {
         enable = true;

configs/nixos/hosts/pikachu/default.nix

@@ -198,6 +198,13 @@
           "dthumb"
         ];
       };
+      "/opds" = {
+        hostPath = "/pikachu/data/opds";
+        path = "/pikachu/data/opds";
+        access.r = [ "alexion" ];
+        readOnly = true;
+        flags = [ "opds" ];
+      };
     };
   };