From 0eaaf860d1599e496fbd2055e8c6eaa689e76ede Mon Sep 17 00:00:00 2001
From: Raito Bezarius <masterancpp@gmail.com>
Date: Fri, 23 Aug 2024 20:19:11 +0200
Subject: [PATCH] feat(common): enable system wide diff in the activation
 output

This helps me to review what changes could be problematic in advance.

Signed-off-by: Raito Bezarius <masterancpp@gmail.com>
---
 common/base-server.nix | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/common/base-server.nix b/common/base-server.nix
index 0b64935..8752fa1 100644
--- a/common/base-server.nix
+++ b/common/base-server.nix
@@ -60,4 +60,14 @@
 
   security.acme.acceptTerms = true;
   security.acme.defaults.email = "infra@forkos.org";
+
+  # Enable system diffs.
+  system.activationScripts.system-diff = {
+    supportsDryActivation = true; # safe: only outputs to stdout
+    text = ''
+      if [ -e /run/current-system ]; then
+        PATH=$PATH:${pkgs.nix}/bin ${pkgs.nvd}/bin/nvd diff /run/current-system $systemConfig
+      fi
+    '';
+  };
 }