feat(etna): add prometheus and grafana

systems/etna/default.nix

@@ -25,6 +25,7 @@ in {
       ./vaultwarden.nix
       ./forgejo.nix
       ./shlink.nix
+      ./metrics.nix
     ];
 
   age.secrets = mkSecrets {

systems/etna/metrics.nix

@@ -0,0 +1,47 @@
+{...}: {
+  cfTunnels."grafana.uku3lig.net" = "http://localhost:2432";
+
+  services.grafana = {
+    enable = true;
+    settings = {
+      server = {
+        http_port = 2432;
+        root_url = "https://grafana.uku3lig.net";
+      };
+    };
+  };
+
+  services.prometheus = {
+    enable = true;
+    port = 9090;
+
+    globalConfig.scrape_interval = "15s";
+
+    exporters = {
+      node = {
+        enable = true;
+        port = 9091;
+        enabledCollectors = ["systemd"];
+      };
+    };
+
+    scrapeConfigs = [
+      {
+        job_name = "scrape-node";
+        static_configs = [
+          {
+            targets = ["localhost:9091"];
+          }
+        ];
+      }
+      {
+        job_name = "scrape-api-rs";
+        static_configs = [
+          {
+            targets = ["localhost:5001"];
+          }
+        ];
+      }
+    ];
+  };
+}