From 41e0d4691bc35285bb53d0feeb36870acba5859e Mon Sep 17 00:00:00 2001
From: TekH <h.tek@digitaldata.works>
Date: Fri, 6 Mar 2026 11:54:50 +0100
Subject: [PATCH] Add in-memory caching to ReadDefaultConfigQueryHandler

Injected IMemoryCache into ReadDefaultConfigQueryHandler and updated the Handle method to cache the default configuration for 30 minutes. This reduces database queries and improves performance for frequently accessed configuration data.
---
 .../Queries/ReadDefaultConfigQuery.cs         | 20 +++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/EnvelopeGenerator.Application/Configuration/Queries/ReadDefaultConfigQuery.cs b/EnvelopeGenerator.Application/Configuration/Queries/ReadDefaultConfigQuery.cs
index 0edf6f56..82f6314f 100644
--- a/EnvelopeGenerator.Application/Configuration/Queries/ReadDefaultConfigQuery.cs
+++ b/EnvelopeGenerator.Application/Configuration/Queries/ReadDefaultConfigQuery.cs
@@ -1,10 +1,13 @@
 using AutoMapper;
 using DigitalData.Core.Abstraction.Application.Repository;
 using DigitalData.Core.Exceptions;
+using EnvelopeGenerator.Application.Common;
 using EnvelopeGenerator.Application.Common.Dto;
 using EnvelopeGenerator.Domain.Entities;
 using MediatR;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Caching.Distributed;
+using Microsoft.Extensions.Caching.Memory;
 
 namespace EnvelopeGenerator.Application.Configuration.Queries;
 
@@ -28,15 +31,19 @@ public class ReadDefaultConfigQueryHandler : IRequestHandler<ReadDefaultConfigQu
 
     private readonly IMapper _mapper;
 
+    private readonly IMemoryCache _cache;
+
     /// <summary>
     /// 
     /// </summary>
     /// <param name="repo"></param>
     /// <param name="mapper"></param>
-    public ReadDefaultConfigQueryHandler(IRepository<Config> repo, IMapper mapper)
+    /// <param name="cache"></param>
+    public ReadDefaultConfigQueryHandler(IRepository<Config> repo, IMapper mapper, IMemoryCache cache)
     {
         _repo = repo;
         _mapper = mapper;
+        _cache = cache;
     }
 
     /// <summary>
@@ -48,10 +55,15 @@ public class ReadDefaultConfigQueryHandler : IRequestHandler<ReadDefaultConfigQu
     /// <exception cref="InvalidOperationException"></exception>
     public async Task<ConfigDto> Handle(ReadDefaultConfigQuery request, CancellationToken cancel)
     {
-        var config = request.EnforceSingleResult
-            ? await _repo.Query.SingleOrDefaultAsync(cancel)
-            : await _repo.Query.FirstOrDefaultAsync(cancel)
+        var config = await _cache.GetOrCreateAsync(CacheKey.DefaultConfig, entry =>
+        {
+            entry.AbsoluteExpirationRelativeToNow = TimeSpan.FromMinutes(30);
+            return request.EnforceSingleResult
+            ? _repo.Query.SingleOrDefaultAsync(cancel)
+            : _repo.Query.FirstOrDefaultAsync(cancel)
             ?? throw new NotFoundException("Default configuration could not be found. Ensure at least one configuration record exists in the database.");
+        });
+
         return _mapper.Map<ConfigDto>(config);
     }
 }
\ No newline at end of file