From 139033130f48be7f9edae9d235d928c9e5faa59c Mon Sep 17 00:00:00 2001
From: fi <fiona@grzb.de>
Date: Fri, 22 Aug 2025 18:47:20 +0200
Subject: [PATCH] Enable metrics for matrix-synapse

---
 config/hosts/matrix/configuration.nix  |  2 +-
 config/hosts/matrix/matrix-synapse.nix | 53 +++++++++++++++++---------
 config/hosts/metrics/nginx.nix         | 19 ---------
 config/hosts/metrics/prometheus.nix    | 18 ++++++++-
 4 files changed, 52 insertions(+), 40 deletions(-)

diff --git a/config/hosts/matrix/configuration.nix b/config/hosts/matrix/configuration.nix
index 9ffa4c6..a52998c 100644
--- a/config/hosts/matrix/configuration.nix
+++ b/config/hosts/matrix/configuration.nix
@@ -9,7 +9,7 @@
     hostName = "matrix";
     firewall = {
       enable = true;
-      allowedTCPPorts = [ 80 8443 8448 ];
+      allowedTCPPorts = [ 80 8443 8448 9000 ];
     };
   };
 
diff --git a/config/hosts/matrix/matrix-synapse.nix b/config/hosts/matrix/matrix-synapse.nix
index 82b82e1..371eb95 100644
--- a/config/hosts/matrix/matrix-synapse.nix
+++ b/config/hosts/matrix/matrix-synapse.nix
@@ -3,26 +3,40 @@
   services.matrix-synapse = {
     enable = true;
     settings = {
-      listeners = [{
-        port = 8008;
-        bind_addresses = [
-          "::1"
-          "127.0.0.1"
-        ];
-        type = "http";
-        tls = false;
-        x_forwarded = true;
-        resources = [
-          {
-            compress = true;
-            names = [ "client" ];
-          }
-          {
+      listeners = [
+        {
+          port = 8008;
+          bind_addresses = [
+            "::1"
+            "127.0.0.1"
+          ];
+          type = "http";
+          tls = false;
+          x_forwarded = true;
+          resources = [
+            {
+              compress = true;
+              names = [ "client" ];
+            }
+            {
+              compress = false;
+              names = [ "federation" ];
+            }
+          ];
+        }
+        {
+          port = 9000;
+          type = "http";
+          tls = false;
+          bind_addresses = [
+            "0.0.0.0"
+          ];
+          resources = [{
+            names = [ "metrics" ];
             compress = false;
-            names = [ "federation" ];
-          }
-        ];
-      }];
+          }];
+        }
+      ];
       server_name = "nekover.se";
       public_baseurl = "https://matrix.nekover.se";
       database = {
@@ -40,6 +54,7 @@
       signing_key_path = "/secrets/matrix-homeserver-signing-key.secret";
       admin_contact = "mailto:admin@nekover.se";
       web_client_location = "https://element.nekover.se";
+      enable_metrics = true;
       turn_uris = [
         "turns:turn.nekover.se?transport=udp"
         "turns:turn.nekover.se?transport=tcp"
diff --git a/config/hosts/metrics/nginx.nix b/config/hosts/metrics/nginx.nix
index aefb0b5..9e31454 100644
--- a/config/hosts/metrics/nginx.nix
+++ b/config/hosts/metrics/nginx.nix
@@ -22,25 +22,6 @@
           proxyWebsockets = true;
         };
       };
-      "alertmanager.grzb.de"= {
-        forceSSL = true;
-        enableACME = true;
-        listen = [
-          {
-            addr = "0.0.0.0";
-            port = 80;
-          }
-          {
-            addr = "0.0.0.0";
-            port = 443;
-            ssl = true;
-          }
-        ];
-        locations."/" = {
-          proxyPass = "http://${config.services.prometheus.alertmanager.listenAddress}:${builtins.toString config.services.prometheus.alertmanager.port}";
-          proxyWebsockets = true;
-        };
-      };
     };
   };
 }
diff --git a/config/hosts/metrics/prometheus.nix b/config/hosts/metrics/prometheus.nix
index 236fb58..0163c43 100644
--- a/config/hosts/metrics/prometheus.nix
+++ b/config/hosts/metrics/prometheus.nix
@@ -1,8 +1,16 @@
-{ hosts, ... }:
+{ hosts, pkgs, ... }:
+let
+  # https://github.com/element-hq/synapse/tree/master/contrib/prometheus/
+  synapseRules = pkgs.fetchurl {
+    url = "https://raw.githubusercontent.com/element-hq/synapse/refs/heads/master/contrib/prometheus/synapse-v2.rules";
+    hash = "sha256-WldlBdCMzul49OlFhJMsrx4MYFakHTa36Y9HnV22EwI=";
+  };
+in
 {
   services.prometheus = {
     enable = true;
     retentionTime = "90d";
+    ruleFiles = [ synapseRules ];
     scrapeConfigs = [
       {
         job_name = "node";
@@ -15,6 +23,14 @@
           };
         }) (builtins.attrNames hosts);
       }
+      {
+        job_name = "synapse";
+        scrape_interval = "15s";
+        metrics_path = "/_synapse/metrics";
+        static_configs = [{
+          targets = [ "matrix.vs.grzb.de:9000" ];
+        }];
+      }
     ];
   };
 }