prometheus/module.nix: init

modules/services/prometheus/module.nix

@@ -0,0 +1,57 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}: let
+  inherit (lib.modules) mkIf;
+  inherit (lib.options) mkEnableOption;
+
+  cfg = config.modules.system.services.grafana;
+  port = 4022;
+in {
+  options.modules.system.services.prometheus.enable = mkEnableOption "Grafana, a graphing service";
+
+  config = mkIf cfg.enable {
+    networking.firewall.allowedTCPPorts = [config.services.grafana.settings.server.http_port];
+
+    modules.system.services.database.postgresql.enable = true;
+
+    services.prometheus = {
+      enable = true;
+      package = pkgs.prometheus;
+      inherit port;
+
+      exporters = {
+        node = {
+          enable = true;
+          port = 4023;
+          enabledCollectors = ["systemd" "processes"];
+        };
+
+        postgres = {
+          enable = true;
+          port = 4024;
+          user = "postgres";
+        };
+      };
+      scrapeConfigs = [
+        {
+          job_name = "prometheus";
+          scrape_interval = "30s";
+          static_configs = [{targets = ["localhost:${toString port}"];}];
+        }
+        {
+          job_name = "node";
+          scrape_interval = "30s";
+          static_configs = [{targets = ["localhost:${toString config.services.prometheus.exporters.node.port}"];}];
+        }
+        {
+          job_name = "postgres";
+          scrape_interval = "30s";
+          static_configs = [{targets = ["localhost:${toString config.services.prometheus.exporters.postgres.port}"];}];
+        }
+      ];
+    };
+  };
+}