modules/prometheus: move to monitor directory

modules/nixos/monitor/restic.nix

@@ -0,0 +1,58 @@
+{ config, lib, ... }:
+let
+  cfg = config.custom.prometheus;
+in
+{
+  config = {
+    services.restic.server.prometheus = true;
+
+    custom.prometheus.templates.scrape.mkResticScrapes =
+      {
+        address,
+        port ? null,
+        ...
+      }:
+      let
+        portStr = if port then ":${toString port}" else "";
+      in
+      [
+        (lib.mkIf cfg.exporters.restic.enable {
+          job_name = "restic";
+          static_configs = [ { targets = [ "${address}${portStr}" ]; } ];
+        })
+      ];
+
+    custom.prometheus.templates.rules.mkResticRules = [
+      {
+        name = "restic_alerts";
+        rules = [
+          {
+            alert = "ResticCheckFailed";
+            expr = "restic_check_success == 0";
+            for = "5m";
+            labels = {
+              severity = "critical";
+            };
+            annotations = {
+              summary = "Restic check failed (instance {{ $labels.instance }})";
+              description = "Restic check failed\\n  VALUE = {{ $value }}\\n  LABELS = {{ $labels }}";
+            };
+          }
+          {
+            alert = "ResticOutdatedBackup";
+            expr = "time() - restic_backup_timestamp > 518400";
+            for = "0m";
+            labels = {
+              severity = "critical";
+            };
+            annotations = {
+              summary = "Restic {{ $labels.client_hostname }} / {{ $labels.client_username }} backup is outdated";
+              description = "Restic backup is outdated\\n  VALUE = {{ $value }}\\n  LABELS = {{ $labels }}";
+            };
+          }
+        ];
+      }
+    ];
+  };
+
+}