From 0b6317accb896944d8632d4f02a2aabc6ea4a789 Mon Sep 17 00:00:00 2001
From: Stephan de Wit <stephan.de.wit@deciso.com>
Date: Tue, 22 Aug 2023 08:50:45 +0200
Subject: [PATCH] MVC: Add allowEmpty option to UniqueConstraint

This is useful in cases where "empty" has special meaning, but is allowed
to occur multiple times, while any set value still has to adhere
to the unique constraint.
---
 .../OPNsense/Base/Constraints/UniqueConstraint.php       | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/opnsense/mvc/app/models/OPNsense/Base/Constraints/UniqueConstraint.php b/src/opnsense/mvc/app/models/OPNsense/Base/Constraints/UniqueConstraint.php
index 2c194d6e1..1390084c6 100644
--- a/src/opnsense/mvc/app/models/OPNsense/Base/Constraints/UniqueConstraint.php
+++ b/src/opnsense/mvc/app/models/OPNsense/Base/Constraints/UniqueConstraint.php
@@ -45,9 +45,18 @@ class UniqueConstraint extends BaseConstraint
      */
     public function validate($validator, $attribute): bool
     {
+        $allowEmpty = ($this->getOption('allowEmpty') === 'Y') ? true : false;
+        if ($allowEmpty && !empty($this->getOptionValueList('addFields'))) {
+            throw new \Exception('UniqueConstraint allowEmpty and addFields cannot be used in tandem');
+        }
+
         $node = $this->getOption('node');
         $fieldSeparator = chr(10) . chr(0);
         if ($node) {
+            if ($allowEmpty && empty((string)$node)) {
+                return true;
+            }
+
             $containerNode = $node;
             $nodeName = $node->getInternalXMLTagName();
             $parentNode = $node->getParentNode();