create grafana and prometheus setup

modules/monitoring.nix

@@ -0,0 +1,23 @@
+{ config, pkgs, ... }:
+  let 
+    domain = "monitoring.${config.networking.domain}";
+  in {
+    # grafana configuration
+    services.grafana = {
+      enable = true;
+      port = 2342;
+    };
+    
+    services.prometheus = {
+      enable = true;
+      port = 9001;
+    };
+
+    # nginx reverse proxy
+    services.nginx.virtualHosts.${domain} = {
+      locations."/" = {
+          proxyPass = "http://localhost:${toString config.services.grafana.port}";
+          proxyWebsockets = true;
+      };
+    };
+}