Merge: nixos/vmalert: support multiple instances (#410856)

doc/release-notes/rl-2511.section.md

@@ -24,6 +24,9 @@
 
 - Added `rewriteURL` attribute to the nixpkgs `config`, to allow for rewriting the URLs downloaded by `fetchurl`.
 
+- `vmalert` now supports multiple instances with the option `services.vmalert.instances."".enable`
+  et al..
+
 ## Nixpkgs Library {#sec-nixpkgs-release-25.11-lib}
 
 <!-- To avoid merge conflicts, consider adding your item at an arbitrary place in the list instead. -->

nixos/doc/manual/release-notes/rl-2305.section.md

@@ -105,7 +105,7 @@ In addition to numerous new and updated packages, this release has the following
 
 - [ivpn](https://www.ivpn.net/), a secure, private VPN with fast WireGuard connections. Available as [services.ivpn](#opt-services.ivpn.enable).
 
-- [vmalert](https://victoriametrics.com/), an alerting engine for VictoriaMetrics. Available as [services.vmalert](#opt-services.vmalert.enable).
+- [vmalert](https://victoriametrics.com/), an alerting engine for VictoriaMetrics. Available as [services.vmalert.instances](#opt-services.vmalert.instances._name_.enable).
 
 - [jellyseerr](https://github.com/Fallenbagel/jellyseerr), a web-based requests manager for Jellyfin, forked from Overseerr. Available as [services.jellyseerr](#opt-services.jellyseerr.enable).
 

nixos/modules/services/monitoring/vmalert.nix

@@ -10,9 +10,9 @@ let
 
   format = pkgs.formats.yaml { };
 
-  confOpts = concatStringsSep " \\\n" (
-    mapAttrsToList mkLine (filterAttrs (_: v: v != false) cfg.settings)
-  );
+  mkConfOpts =
+    settings:
+    concatStringsSep " \\\n" (mapAttrsToList mkLine (filterAttrs (_: v: v != false) settings));
   confType =
     with types;
     let
@@ -33,10 +33,41 @@ let
       concatMapStringsSep " " (v: "-${key}=${escapeShellArg (toString v)}") value
     else
       "-${key}=${escapeShellArg (toString value)}";
+
+  vmalertName = name: "vmalert" + lib.optionalString (name != "") ("-" + name);
+  enabledInstances = lib.filterAttrs (name: conf: conf.enable) config.services.vmalert.instances;
 in
 {
+  imports = [
+    (lib.mkRenamedOptionModule
+      [ "services" "vmalert" "enable" ]
+      [ "services" "vmalert" "instances" "" "enable" ]
+    )
+    (lib.mkRenamedOptionModule
+      [ "services" "vmalert" "rules" ]
+      [ "services" "vmalert" "instances" "" "rules" ]
+    )
+    (lib.mkRenamedOptionModule
+      [ "services" "vmalert" "settings" ]
+      [ "services" "vmalert" "instances" "" "settings" ]
+    )
+  ];
+
   # interface
-  options.services.vmalert = {
+  options.services.vmalert.package = mkPackageOption pkgs "victoriametrics" { };
+
+  options.services.vmalert.instances = mkOption {
+    default = { };
+
+    description = ''
+      Define multiple instances of vmalert.
+    '';
+
+    type = types.attrsOf (
+      types.submodule (
+        { name, config, ... }:
+        {
+          options = {
             enable = lib.mkOption {
               type = lib.types.bool;
               default = false;
@@ -47,8 +78,6 @@ in
               '';
             };
 
-    package = mkPackageOption pkgs "victoriametrics" { };
-
             settings = mkOption {
               type = types.submodule {
                 freeformType = confType;
@@ -77,7 +106,7 @@ in
                       Path to the files with alerting and/or recording rules.
 
                       ::: {.note}
-              Consider using the {option}`services.vmalert.rules` option as a convenient alternative for declaring rules
+                      Consider using the {option}`services.vmalert.instances.<name>.rules` option as a convenient alternative for declaring rules
                       directly in the `nix` language.
                       :::
                     '';
@@ -130,27 +159,45 @@ in
             };
           };
 
-  # implementation
-  config = mkIf cfg.enable {
-
-    environment.etc."vmalert/rules.yml".source = format.generate "rules.yml" cfg.rules;
-
-    services.vmalert.settings.rule = [
-      "/etc/vmalert/rules.yml"
+          config = {
+            settings.rule = [
+              "/etc/${vmalertName name}/rules.yml"
             ];
+          };
+        }
+      )
+    );
+  };
 
-    systemd.services.vmalert = {
+  # implementation
+  config = mkIf (enabledInstances != { }) {
+    environment.etc = lib.mapAttrs' (
+      name:
+      { rules, ... }:
+      lib.nameValuePair "${vmalertName name}/rules.yml" {
+        source = format.generate "rules.yml" rules;
+      }
+    ) enabledInstances;
+
+    systemd.services = lib.mapAttrs' (
+      name:
+      { settings, ... }:
+      let
+        name' = vmalertName name;
+      in
+      lib.nameValuePair name' {
         description = "vmalert service";
         wantedBy = [ "multi-user.target" ];
         after = [ "network.target" ];
-      reloadTriggers = [ config.environment.etc."vmalert/rules.yml".source ];
+        reloadTriggers = [ config.environment.etc."${name'}/rules.yml".source ];
 
         serviceConfig = {
           DynamicUser = true;
           Restart = "on-failure";
-        ExecStart = "${cfg.package}/bin/vmalert ${confOpts}";
+          ExecStart = "${cfg.package}/bin/vmalert ${mkConfOpts settings}";
           ExecReload = ''${pkgs.coreutils}/bin/kill -SIGHUP "$MAINPID"'';
         };
-    };
+      }
+    ) enabledInstances;
   };
 }

nixos/tests/victoriametrics/vmalert.nix

@@ -55,7 +55,7 @@ import ../make-test-python.nix (
             };
           };
 
-          services.vmalert = {
+          services.vmalert.instances."" = {
             enable = true;
             settings = {
               "datasource.url" = "http://localhost:8428"; # victoriametrics' api