feat(matrix-synapse): enable metrics

Following:
https://github.com/matrix-org/synapse/blob/develop/docs/metrics-howto.md

hosts/flora-6/apps/prometheus.nix

@@ -26,7 +26,7 @@
     };
     scrapeConfigs = [
       {
-        job_name = "http-targets";
+        job_name = "node-exporter-http";
         static_configs = [{
           targets = [ "127.0.0.1:${toString config.services.prometheus.exporters.node.port}" ];
           labels = {
@@ -35,7 +35,7 @@
         }];
       }
       {
-        job_name = "https-targets";
+        job_name = "node-exporter-https";
         scheme = "https";
         metrics_path = "/metrics";
         basic_auth = {
@@ -49,6 +49,21 @@
           };
         }];
       }
+      {
+        job_name = "matrix-synapse";
+        scheme = "https";
+        metrics_path = "/_synapse/metrics";
+        basic_auth = {
+          username = "hakkonaut";
+          password_file = "${config.age.secrets.nachtigall-metrics-prometheus-basic-auth-password.path}";
+        };
+        static_configs = [{
+          targets = [ "nachtigall.pub.solar" ];
+          labels = {
+            instance = "nachtigall";
+          };
+        }];
+      }
     ];
   };
 }

hosts/nachtigall/apps/matrix/synapse.nix

@@ -38,6 +38,32 @@ in
         allow_unsafe_locale = false;
         txn_limit = 0;
       };
+      listeners = [
+        {
+          bind_addresses = [
+            "127.0.0.1"
+          ];
+          port = 8008;
+          resources = [
+            {
+              compress = true;
+              names = [
+                "client"
+              ];
+            }
+            {
+              compress = false;
+              names = [
+                "federation"
+                "metrics"
+              ];
+            }
+          ];
+          tls = false;
+          type = "http";
+          x_forwarded = true;
+        }
+      ];
 
       account_threepid_delegates.msisdn = "";
       alias_creation_rules = [{
@@ -68,6 +94,7 @@ in
       encryption_enabled_by_default_for_room_type = "off";
       event_cache_size = "100K";
       federation_rr_transactions_per_room_per_second = 50;
+      federation_client_minimum_tls_version = "1.2";
       forget_rooms_on_leave = true;
       include_profile_data_on_invite = true;
       instance_map = { };
@@ -162,6 +189,7 @@ in
 
       stream_writers = { };
       trusted_key_servers = [{ server_name = "matrix.org"; }];
+      suppress_key_server_warning = true;
 
       turn_allow_guests = false;
       turn_uris = [
@@ -213,6 +241,8 @@ in
       ];
     };
 
+    withJemalloc = true;
+
     extraConfigFiles = [
       "/run/agenix/matrix-synapse-secret-config.yaml"
 

hosts/nachtigall/apps/nginx-matrix.nix

@@ -88,10 +88,6 @@ in
         gzip_types text/plain application/json;
       '';
       locations = {
-        # TODO: Configure metrics
-        # "/metrics" = {
-        # };
-
         # For telegram
         "/c3c3f34b-29fb-5feb-86e5-98c75ec8214b" = {
           proxyPass = "http://127.0.0.1:8009";

hosts/nachtigall/apps/nginx-prometheus-exporters.nix

@@ -14,6 +14,9 @@
       locations."/metrics" = {
         proxyPass = "http://127.0.0.1:${toString(config.services.prometheus.exporters.node.port)}";
       };
+      locations."/_synapse/metrics" = {
+        proxyPass = "http://127.0.0.1:${toString (builtins.map (listener: listener.port) config.services.matrix-synapse.settings.listeners)}";
+      };
     };
   };
 }