From b1cd6018baad1dd73e8d10cd6be0b633e8682b47 Mon Sep 17 00:00:00 2001
From: fruchti <fruchti@gvfr.de>
Date: Sun, 30 Mar 2025 20:54:22 +0200
Subject: [PATCH] Disallow auto-reboot when users are active

---
 hosts/Rupert.nix         |  1 +
 options/auto-upgrade.nix | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/hosts/Rupert.nix b/hosts/Rupert.nix
index 627b201..f2f822f 100644
--- a/hosts/Rupert.nix
+++ b/hosts/Rupert.nix
@@ -119,6 +119,7 @@ in
         gitPull = true;
         gitDeploymentKeyFile = "/secrets/ssh_id_gitea_nixos_configuration";
         gitUser = "fruchti";
+        rebootIgnoreUsersActive = [ "waldi" ];
     };
 
     # systemd.services.nixos-upgrade.onFailure = lib.mkIf config.system.autoUpgrade.enable [ "status-email@%n.service" ];
diff --git a/options/auto-upgrade.nix b/options/auto-upgrade.nix
index 9a84200..d0f9829 100644
--- a/options/auto-upgrade.nix
+++ b/options/auto-upgrade.nix
@@ -36,6 +36,13 @@ in
                 User used for the `git pull` operation (if `gitPull` is enabled).
             '';
         };
+        rebootIgnoreUsersActive = mkOption {
+            type = types.listOf types.str;
+            default = [];
+            description = mdDoc ''
+                If reboots are allowed, active users will prohibit a reboot. Users listed here are ignored from that check.
+            '';
+        };
     };
 
     config = mkIf cfg.enable {
@@ -156,6 +163,14 @@ in
                 EOF
                         )"
                         activate_configuration="no"
+
+                        # Check if any user sessions are open
+                        active_users=$(users | tr ' ' '\n' | sort | uniq | grep -vE '^(${concatStringsSep "|" cfg.rebootIgnoreUsersActive})$')
+                        if [ "$reboot_allowed" = "yes" ] && [ -n "$active_users" ] ; then
+                            reboot_allowed=no
+                            email_body="$(printf "%s\n%s\n%s" "$email_body" "The system cannot reboot since the following users are active:" "$active_users")"
+                        fi
+
                         if [ "$reboot_allowed" = "yes" ] && [ $exit_code -eq 0 ] ; then
                             email_body="$(printf "%s\n%s" "$email_body" "The system will reboot now.")"
                             do_reboot="yes"