services: add jellyfin

This makes use of the 'media' group, to allow using the same group for
any software that would either read or write to my media collection.

configuration.nix

@@ -74,6 +74,8 @@
   my.services = {
     # Gitea forge
     gitea.enable = true;
+    # Jellyfin media server
+    jellyfin.enable = true;
     # Matrix backend and Element chat front-end
     matrix.enable = true;
   };

services/default.nix

@@ -3,7 +3,9 @@
 {
   imports = [
     ./gitea.nix
+    ./jellyfin.nix
     ./matrix.nix
+    ./media.nix
     ./nginx.nix
   ];
 }

services/jellyfin.nix

@@ -0,0 +1,27 @@
+# A FLOSS media server
+{ config, lib, ... }:
+let
+  cfg = config.my.services.jellyfin;
+  domain = config.networking.domain;
+  jellyfinDomain = "jellyfin.${config.networking.domain}";
+in
+{
+  options.my.services.jellyfin = {
+    enable = lib.mkEnableOption "Jellyfin Media Server";
+  };
+
+  config = lib.mkIf cfg.enable {
+    services.jellyfin = {
+      enable = true;
+      group = "media";
+    };
+
+    # Proxy to Jellyfin
+    services.nginx.virtualHosts."${jellyfinDomain}" = {
+      forceSSL = true;
+      useACMEHost = "${domain}";
+
+      locations."/".proxyPass = "http://localhost:8096/";
+    };
+  };
+}

services/media.nix

@@ -0,0 +1,10 @@
+# Abstracting away the need for a common 'media' group
+
+{ config, lib, ... }:
+let
+  needed = with config.my.services;
+    jellyfin.enable;
+in
+{
+  config.users.groups.media = lib.mkIf needed { };
+}