From 2bbb8b50108cd1d65b6467cf18fe5100001530ea Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Motiejus=20Jak=C5=A1tys?= <motiejus@jakstys.lt>
Date: Mon, 29 Jul 2024 05:36:17 +0300
Subject: [PATCH] btrfssnapshot

---
 modules/base/btrfssnapshot/default.nix | 53 ++++++++++++++++++++++++++
 modules/base/default.nix               |  1 +
 2 files changed, 54 insertions(+)
 create mode 100644 modules/base/btrfssnapshot/default.nix

diff --git a/modules/base/btrfssnapshot/default.nix b/modules/base/btrfssnapshot/default.nix
new file mode 100644
index 0000000..141fe9d
--- /dev/null
+++ b/modules/base/btrfssnapshot/default.nix
@@ -0,0 +1,53 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}: let
+  cfg = config.mj.base.btrfssnapshot;
+in {
+  options.mj.base.btrfssnapshot = {
+    enable = lib.mkEnableOption "Enable btrfs snapshots";
+
+    subvolumes = lib.mkOption {
+      default = {};
+      type = with lib.types;
+        attrsOf (submodule {
+          options = {
+            label = lib.mkOption {type = str;};
+            keep = lib.mkOption {type = int;};
+            refreshInterval = lib.mkOption {type = str;};
+          };
+        });
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    systemd = {
+      services =
+        lib.mapAttrs'
+        (
+          subvolume: params:
+            lib.nameValuePair
+            "btrfs-snapshot-${lib.strings.sanitizeDerivationName subvolume}"
+            {
+              description = "${params.label} btrfs snapshot for ${subvolume} (keep ${params.keep}";
+              serviceConfig.ExecStart = "${pkgs.btrfs-auto-snapshot} --verbose --label=${params.label} --keep=${params.keep} ${subvolume}";
+            }
+        );
+
+      timers =
+        lib.mapAttrs'
+        (
+          subvolume: params:
+            lib.nameValuePair
+            "btrfs-snapshot-${lib.strings.sanitizeDerivationName subvolume}"
+            {
+              description = "${params.label} btrfs snapshot for ${subvolume}";
+              wantedBy = ["timers.target"];
+              timerConfig.OnCalendar = params.refreshInterval;
+            }
+        );
+    };
+  };
+}
diff --git a/modules/base/default.nix b/modules/base/default.nix
index 7c4544d..172d8b7 100644
--- a/modules/base/default.nix
+++ b/modules/base/default.nix
@@ -9,6 +9,7 @@
 in {
   imports = [
     ./boot
+    ./btrfssnapshot
     ./fileSystems
     ./snapshot
     ./sshd