Refactor user ID validation and optimize city search results. Updated user ID check to use Number.isNaN for better clarity. Added a comment indicating that city results are capped at 50 in the database query to reduce latency.

src/modules/user/handlers/connections/searchCities.ts

@@ -30,7 +30,7 @@ export const handler = safeHandler(
     const userInfo = await verifyUserToken(token);
     const userId = Number(userInfo.id);
 
-    if (!userId || isNaN(userId)) {
+    if (!userId || Number.isNaN(userId)) {
       throw new ApiError(400, 'Invalid user ID');
     }
 
@@ -78,7 +78,7 @@ export const handler = safeHandler(
       body: JSON.stringify({
         success: true,
         message: 'Cities found successfully',
-        data: results,
+        data: results, // already capped at 50 in DB query
         count: results.length,
       }),
     };

src/modules/user/services/user.service.ts

@@ -1932,9 +1932,11 @@ export class UserService {
         id: true,
         cityName: true,
         stateXid: true,
-        isActive: true,
-        createdAt: true,
       },
+      orderBy: {
+        cityName: 'asc',
+      },
+      take: 50, // reduce latency by limiting results at DB level
     });
 
     return results;