prometheus-minio-exporter service: init version

nixos/modules/module-list.nix

@@ -375,6 +375,7 @@
   ./services/monitoring/prometheus/collectd-exporter.nix
   ./services/monitoring/prometheus/fritzbox-exporter.nix
   ./services/monitoring/prometheus/json-exporter.nix
+  ./services/monitoring/prometheus/minio-exporter.nix
   ./services/monitoring/prometheus/nginx-exporter.nix
   ./services/monitoring/prometheus/node-exporter.nix
   ./services/monitoring/prometheus/snmp-exporter.nix

nixos/modules/services/monitoring/prometheus/minio-exporter.nix

@@ -0,0 +1,107 @@
+{ config, pkgs, lib, ... }:
+
+with lib;
+
+let
+  cfg = config.services.prometheus.minioExporter;
+in {
+  options = {
+    services.prometheus.minioExporter = {
+      enable = mkEnableOption "prometheus minio exporter";
+
+      port = mkOption {
+        type = types.int;
+        default = 9290;
+        description = ''
+          Port to listen on.
+        '';
+      };
+
+      listenAddress = mkOption {
+        type = types.nullOr types.str;
+        default = null;
+        example = "0.0.0.0";
+        description = ''
+          Address to listen on for web interface and telemetry.
+        '';
+      };
+
+      minioAddress = mkOption {
+        type = types.str;
+        example = "https://10.0.0.1:9000";
+        description = ''
+          The URL of the minio server.
+          Use HTTPS if Minio accepts secure connections only.
+        '';
+      };
+
+      minioAccessKey = mkOption {
+        type = types.str;
+        example = "BKIKJAA5BMMU2RHO6IBB";
+        description = ''
+          The value of the Minio access key.
+          It is required in order to connect to the server.
+        '';
+      };
+
+      minioAccessSecret = mkOption {
+        type = types.str;
+        description = ''
+          The calue of the Minio access secret.
+          It is required in order to connect to the server.
+        '';
+      };
+
+      minioBucketStats = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Collect statistics about the buckets and files in buckets.
+          It requires more computation, use it carefully in case of large buckets..
+        '';
+      };
+
+      extraFlags = mkOption {
+        type = types.listOf types.str;
+        default = [];
+        description = ''
+          Extra commandline options when launching the minio exporter.
+        '';
+      };
+
+      openFirewall = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Open port in firewall for incoming connections.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    networking.firewall.allowedTCPPorts = optional cfg.openFirewall cfg.port;
+
+    systemd.services.prometheus-minio-exporter = {
+      description = "Prometheus exporter for Minio server metrics";
+      unitConfig.Documentation = "https://github.com/joe-pll/minio-exporter";
+      wantedBy = [ "multi-user.target" ];
+      after = optional config.services.minio.enable "minio.service";
+      serviceConfig = {
+        DynamicUser = true;
+        Restart = "always";
+        PrivateTmp = true;
+        WorkingDirectory = /tmp;
+        ExecStart = ''
+          ${pkgs.prometheus-minio-exporter}/bin/minio-exporter \
+            -web.listen-address ${optionalString (cfg.listenAddress != null) cfg.listenAddress}:${toString cfg.port} \
+            -minio.server ${cfg.minioAddress} \
+            -minio.access-key ${cfg.minioAccessKey} \
+            -minio.access-secret ${cfg.minioAccessSecret} \
+            ${optionalString cfg.minioBucketStats "-minio.bucket-stats"} \
+            ${concatStringsSep " \\\n  " cfg.extraFlags}
+        '';
+      };
+    };
+  };
+}