service/blackbox: init

modules/services/blackbox/default.nix

@@ -0,0 +1,92 @@
+# monitor urls
+{ config, lib, pkgs, ... }:
+let
+  cfg = config.my.services.blackbox;
+  domain = config.networking.domain;
+  blackBoxConfig = {
+    modules = {
+      http_2xx = {
+        prober = "http";
+        http.preferred_ip_protocol = "ip4";
+      };
+      ssh_banner = {
+        prober = "tcp";
+        tcp.query_response = [
+          {
+            send = "SSH-2.0-blackbox-ssh-check";
+          }
+          {
+            expect = "^SSH-2.0-";
+          }
+        ];
+      };
+    };
+  };
+in
+{
+  options.my.services.blackbox = with lib; {
+    enable = mkEnableOption "Blackbox prometheus exporter";
+
+    http_endpoints = mkOption {
+      type = types.listOf types.str;
+      default = [ ];
+      example = literalExpression ''
+        [
+          "https://domain.com"
+          "https://another-domain.com"
+        ]
+      '';
+      description = ''
+        List of domains to test.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    services.prometheus.exporters.blackbox = {
+      enable = true;
+      configFile = pkgs.writeText "blackbox-config.yml" (builtins.toJSON blackBoxConfig);
+    };
+
+    # relabels as in https://github.com/prometheus/blackbox_exporter#prometheus-configuration
+    services.prometheus = {
+      scrapeConfigs = [
+        {
+          job_name = "blackbox";
+          metrics_path = "/probe";
+          params.module = [ "http_2xx" ];
+          static_configs = [
+            {
+              targets = cfg.http_endpoints;
+              labels = {
+                instance = config.networking.hostName;
+              };
+            }
+          ];
+          relabel_configs = [
+            {
+              source_labels = [ "__address__" ];
+              target_label = "__param_target";
+            }
+            {
+              source_labels = [ "__param_target" ];
+              target_label = "instance";
+            }
+            {
+              target_label = "__address__";
+              replacement = "127.0.0.1:${toString config.services.prometheus.exporters.blackbox.port}";
+            }
+          ];
+        }
+      ];
+    };
+
+    services.grafana.provision.dashboards.settings.providers = [
+      {
+        name = "Blackbox";
+        options.path = pkgs.grafana-dashboards.blackbox;
+        disableDeletion = true;
+      }
+    ];
+  };
+}