feat: Implementierung von Caching im EmailTemplateRepository zur Leistungsverbesserung der ReadByNameAsync-Methode.

EnvelopeGenerator.Infrastructure/Repositories/EmailTemplateRepository.cs

@@ -3,16 +3,33 @@ using DigitalData.UserManager.Infrastructure.Repositories;
 using EnvelopeGenerator.Domain.Entities;
 using EnvelopeGenerator.Infrastructure.Contracts;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Caching.Memory;
 using static EnvelopeGenerator.Common.Constants;
 
 namespace EnvelopeGenerator.Infrastructure.Repositories
 {
     public class EmailTemplateRepository : CRUDRepository<EmailTemplate, int, EGDbContext>, IEmailTemplateRepository
     {
-        public EmailTemplateRepository(EGDbContext dbContext) : base(dbContext)
+        private readonly IMemoryCache _cache;
+
+		public EmailTemplateRepository(EGDbContext dbContext, IMemoryCache cache) : base(dbContext)
         {
+            _cache = cache;
         }
 
-        public async Task<EmailTemplate?> ReadByNameAsync(EmailTemplateType type) => await _dbSet.Where(t => t.Name == type.ToString()).FirstOrDefaultAsync();
+        private readonly Guid key_guid = Guid.NewGuid();
+
+		/// <summary>
+		/// Retrieves an email template based on its name. 
+		/// Utilizes in-memory caching to improve performance for the limited number of email templates available.
+		/// If the template is not found in the cache, it queries the database and stores the result in the cache.
+		/// </summary>
+		/// <param name="type">The type of the email template, which corresponds to its name.</param>
+		/// <returns>
+		/// A task that represents the asynchronous operation. The task result contains the email template 
+		/// if found, otherwise null.
+		/// </returns>
+		public async Task<EmailTemplate?> ReadByNameAsync(EmailTemplateType type) => await _cache.GetOrCreateAsync($"{type}{key_guid}", async _
+            => await _dbSet.Where(t => t.Name == type.ToString()).FirstOrDefaultAsync());
     }
 }