From 8423db2858cadd25c0a56245ea9bbf51a3b841f0 Mon Sep 17 00:00:00 2001
From: Tom Butcher <thomasbutcher15@gmail.com>
Date: Sun, 26 Jul 2026 15:00:37 +0100
Subject: [PATCH] Implemented a merge utility function for object updates in
 database.js to handle array merging correctly, enhancing cache update logic
 for improved data integrity.

---
 src/database/database.js | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/database/database.js b/src/database/database.js
index 98d2343..da9334a 100644
--- a/src/database/database.js
+++ b/src/database/database.js
@@ -37,6 +37,13 @@ cacheLogger.level = config.server.logLevel;
 
 const CACHE_TTL_SECONDS = parseInt(config.database.redis.cacheTtl || '30', 10);
 
+const mergeObjectUpdates = (target, source) =>
+  _.mergeWith(target, source, (objValue, srcValue) => {
+    if (Array.isArray(objValue) || Array.isArray(srcValue)) {
+      return srcValue;
+    }
+  });
+
 export const retrieveObjectCache = async ({ model, id, populate = [] }) => {
   if (!model || !id) return undefined;
 
@@ -79,13 +86,13 @@ export const updateObjectCache = async ({ model, id, object, populate = [] }) =>
     for (const key of matchingKeys) {
       logger.trace('Updating object cache:', key);
       const cachedObject = (await redisServer.getKey(key)) || {};
-      const mergedObject = _.merge(cachedObject, object);
+      const mergedObject = mergeObjectUpdates(cachedObject, object);
       await redisServer.setKey(key, mergedObject, CACHE_TTL_SECONDS);
       mergedObjects.push(mergedObject);
     }
 
     const cacheObject = (await redisServer.getKey(cacheKey)) || {};
-    const mergedObject = _.merge(cacheObject, object);
+    const mergedObject = mergeObjectUpdates(cacheObject, object);
     await redisServer.setKey(cacheKey, mergedObject, CACHE_TTL_SECONDS);
 
     cacheLogger.trace('Updated object cache:', {