nixos/prometheus.exporters.dnssec: init module

nixos/modules/services/monitoring/prometheus/exporters.nix

@@ -31,6 +31,7 @@ let
     "collectd"
     "dmarc"
     "dnsmasq"
+    "dnssec"
     "domain"
     "dovecot"
     "fastly"

nixos/modules/services/monitoring/prometheus/exporters/dnssec.nix

@@ -0,0 +1,90 @@
+{ config, lib, pkgs, ... }:
+let
+  cfg = config.services.prometheus.exporters.dnssec;
+  configFormat = pkgs.formats.toml { };
+  configFile = configFormat.generate "dnssec-checks.toml" cfg.configuration;
+in {
+  port = 9204;
+  extraOpts = {
+    configuration = lib.mkOption {
+      type = lib.types.nullOr lib.types.attrs;
+      default = null;
+      description = ''
+        dnssec exporter configuration as nix attribute set.
+
+        See <https://github.com/chrj/prometheus-dnssec-exporter/blob/master/README.md>
+        for the description of the configuration file format.
+      '';
+      example = lib.literalExpression ''
+        {
+          records = [
+            {
+              zone = "ietf.org";
+              record = "@";
+              type = "SOA";
+            }
+            {
+              zone = "verisigninc.com";
+              record = "@";
+              type = "SOA";
+            }
+          ];
+        }
+      '';
+    };
+
+    listenAddress = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      description = ''
+        Listen address as host IP and port definition.
+      '';
+      example = ":9204";
+    };
+
+    resolvers = lib.mkOption {
+      type = lib.types.listOf lib.types.str;
+      default = [ ];
+      description = ''
+        DNSSEC capable resolver to be used for the check.
+      '';
+      example = [ "0.0.0.0:53" ];
+    };
+
+    timeout = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      description = ''
+        DNS request timeout duration.
+      '';
+      example = "10s";
+    };
+
+    extraFlags = lib.mkOption {
+      type = lib.types.listOf lib.types.str;
+      default = [ ];
+      description = ''
+        Extra commandline options when launching Prometheus.
+      '';
+    };
+  };
+
+  serviceOpts = {
+    serviceConfig = let
+      startScript = pkgs.writeShellScriptBin "prometheus-dnssec-exporter-start"
+        "${lib.concatStringsSep " "
+        ([ "${pkgs.prometheus-dnssec-exporter}/bin/prometheus-dnssec-exporter" ]
+          ++ lib.optionals (cfg.configuration != null)
+          [ "-config ${configFile}" ]
+          ++ lib.optionals (cfg.listenAddress != null)
+          [ "-listen-address ${lib.escapeShellArg cfg.listenAddress}" ]
+          ++ lib.optionals (cfg.resolvers != [ ]) [
+            "-resolvers ${
+              lib.escapeShellArg (lib.concatStringsSep "," cfg.resolvers)
+            }"
+          ] ++ lib.optionals (cfg.timeout != null)
+          [ "-timeout ${lib.escapeShellArg cfg.timeout}" ] ++ cfg.extraFlags)}";
+    in { ExecStart = lib.getExe startScript; };
+  };
+}
+