From 1515ce28e4fb6fc7a207eb0cc66974c3503e8630 Mon Sep 17 00:00:00 2001
From: SebastianStork <sebastian.stork@pm.me>
Date: Mon, 22 Sep 2025 00:28:47 +0200
Subject: [PATCH] alloy: Add caddy metrics scraping

---
 hosts/srv-monitor/default.nix     |  1 +
 hosts/srv-private/default.nix     |  5 ++++-
 hosts/srv-public/default.nix      |  5 ++++-
 modules/system/services/alloy.nix | 19 ++++++++++++++++++-
 4 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/hosts/srv-monitor/default.nix b/hosts/srv-monitor/default.nix
index f99f913..3ef3e6e 100644
--- a/hosts/srv-monitor/default.nix
+++ b/hosts/srv-monitor/default.nix
@@ -82,6 +82,7 @@
           collect.metrics = {
             system = true;
             victorialogs = true;
+            caddy = true;
           };
         };
 
diff --git a/hosts/srv-private/default.nix b/hosts/srv-private/default.nix
index 130ebe7..951fac3 100644
--- a/hosts/srv-private/default.nix
+++ b/hosts/srv-private/default.nix
@@ -56,7 +56,10 @@
         alloy = {
           enable = true;
           domain = "alloy-${config.networking.hostName}.${tailscaleDomain}";
-          collect.metrics.system = true;
+          collect.metrics = {
+            system = true;
+            caddy = true;
+          };
         };
 
         caddy.virtualHosts =
diff --git a/hosts/srv-public/default.nix b/hosts/srv-public/default.nix
index 6c5132e..b54effa 100644
--- a/hosts/srv-public/default.nix
+++ b/hosts/srv-public/default.nix
@@ -78,7 +78,10 @@
           enable = true;
           domain = "alloy-${config.networking.hostName}.${config.custom.services.tailscale.domain}";
           collect = {
-            metrics.system = true;
+            metrics = {
+              system = true;
+              caddy = true;
+            };
             logs.sshd = true;
           };
         };
diff --git a/modules/system/services/alloy.nix b/modules/system/services/alloy.nix
index c8e5173..b7c73fa 100644
--- a/modules/system/services/alloy.nix
+++ b/modules/system/services/alloy.nix
@@ -25,6 +25,7 @@ in
       metrics = {
         system = lib.mkEnableOption "";
         victorialogs = lib.mkEnableOption "";
+        caddy = lib.mkEnableOption "";
       };
       logs.sshd = lib.mkEnableOption "";
     };
@@ -36,6 +37,10 @@ in
         assertion = cfg.collect.metrics.victorialogs -> config.services.victorialogs.enable;
         message = "Collecting VictoriaLogs metrics requires the VictoriaLogs service to be enabled.";
       }
+      {
+        assertion = cfg.collect.metrics.caddy -> config.services.caddy.enable;
+        message = "Collecting Caddy metrics requires the Caddy service to be enabled.";
+      }
       {
         assertion = cfg.collect.logs.sshd -> config.services.openssh.enable;
         message = "Collecting OpenSSH logs requires the OpenSSH service to be enabled.";
@@ -101,7 +106,19 @@ in
             prometheus.scrape "victorialogs" {
               targets = [{
                 __address__ = "localhost:${builtins.toString config.custom.services.victorialogs.port}",
-                job         = "victorialogs",
+                instance    = constants.hostname,
+              }]
+              forward_to      = [prometheus.remote_write.default.receiver]
+              scrape_interval = "15s"
+            }
+          '';
+        };
+        "alloy/caddy-metrics.alloy" = {
+          enable = cfg.collect.metrics.caddy;
+          text = ''
+            prometheus.scrape "caddy" {
+              targets = [{
+                __address__ = "localhost:2019",
                 instance    = constants.hostname,
               }]
               forward_to      = [prometheus.remote_write.default.receiver]