Avoid full store list materialization in core fallback paths

src/Business/Grand.Business.Common/Services/Stores/StoreService.cs

@@ -56,6 +56,16 @@ public virtual async Task<IList<Store>> GetAllStores()
         });
     }
 
+    /// <summary>
+    ///     Gets the first configured store
+    /// </summary>
+    /// <returns>Store</returns>
+    public virtual Task<Store?> GetFirstStore()
+    {
+        return _cacheBase.GetAsync(CacheKey.STORES_FIRST_KEY, () => Task.FromResult(
+            _storeRepository.Table.OrderBy(x => x.DisplayOrder).FirstOrDefault()));
+    }
+
     /// <summary>
     ///     Gets a store
     /// </summary>
@@ -109,8 +119,7 @@ public virtual async Task DeleteStore(Store store)
     {
         ArgumentNullException.ThrowIfNull(store);
 
-        var allStores = await GetAllStores();
-        if (allStores.Count == 1)
+        if (!_storeRepository.Table.Skip(1).Any())
             throw new Exception("You cannot delete the only configured store");
 
         await _storeRepository.DeleteAsync(store);
@@ -128,8 +137,13 @@ public virtual async Task DeleteStore(Store store)
     /// <returns></returns>
     public async Task<Store?> GetStoreByHost(string host)
     {
-        var allStores = await GetAllStores();
-        return allStores.FirstOrDefault(s => s.ContainsHostValue(host));
+        if (string.IsNullOrEmpty(host))
+            return null;
+
+        var key = string.Format(CacheKey.STORES_BY_HOST_KEY, host.ToLowerInvariant());
+        return await _cacheBase.GetAsync(key, () => Task.FromResult(
+            _storeRepository.Table.FirstOrDefault(s =>
+                s.Domains.Any(domain => domain.HostName.Equals(host, StringComparison.OrdinalIgnoreCase)))));
     }
 
     #endregion

src/Business/Grand.Business.Core/Interfaces/Common/Stores/IStoreService.cs

@@ -15,6 +15,12 @@ public interface IStoreService
     /// <returns>Stores</returns>
     Task<IList<Store>> GetAllStores();
 
+    /// <summary>
+    ///     Gets the first configured store
+    /// </summary>
+    /// <returns>Store</returns>
+    Task<Store?> GetFirstStore();
+
     /// <summary>
     ///     Gets a store
     /// </summary>

src/Business/Grand.Business.Marketing/Services/Campaigns/CampaignService.cs

@@ -249,7 +249,7 @@ public virtual async Task<int> SendCampaign(Campaign campaign, EmailAccount emai
 
             var builder = new LiquidObjectBuilder(mediator);
             var store = await storeService.GetStoreById(campaign.StoreId) ??
-                        (await storeService.GetAllStores()).FirstOrDefault();
+                        await storeService.GetFirstStore();
 
             builder.AddStoreTokens(store, language, emailAccount)
                 .AddNewsLetterSubscriptionTokens(subscription, store, contextAccessor.StoreContext.CurrentHost);
@@ -303,7 +303,7 @@ public virtual async Task SendCampaign(Campaign campaign, EmailAccount emailAcco
                        (await languageService.GetAllLanguages()).FirstOrDefault();
 
         var store = await storeService.GetStoreById(campaign.StoreId) ??
-                    (await storeService.GetAllStores()).FirstOrDefault();
+                    await storeService.GetFirstStore();
 
         var builder = new LiquidObjectBuilder(mediator);
         builder.AddStoreTokens(store, language, emailAccount);

src/Business/Grand.Business.Messages/Services/MessageProviderService.cs

@@ -76,7 +76,7 @@ public MessageProviderService(
 
     protected virtual async Task<Store> GetStore(string storeId)
     {
-        return await _storeService.GetStoreById(storeId) ?? (await _storeService.GetAllStores()).FirstOrDefault();
+        return await _storeService.GetStoreById(storeId) ?? await _storeService.GetFirstStore();
     }
 
     protected virtual async Task<MessageTemplate> GetMessageTemplate(string messageTemplateName, string storeId)
@@ -1161,7 +1161,7 @@ public virtual async Task<int> SendGiftVoucherMessage(GiftVoucher giftVoucher, O
 
         Store store = null;
         if (order != null) store = await _storeService.GetStoreById(order.StoreId);
-        store ??= (await _storeService.GetAllStores()).FirstOrDefault();
+        store ??= await _storeService.GetFirstStore();
 
         var language = await EnsureLanguageIsActive(languageId, store?.Id);
 
@@ -1843,7 +1843,7 @@ public virtual async Task<int> SendAuctionEndedStoreOwnerMessage(Product product
         }
         else
         {
-            var store = (await _storeService.GetAllStores()).FirstOrDefault();
+            var store = await _storeService.GetFirstStore();
             var language = await EnsureLanguageIsActive(languageId, store?.Id);
             messageTemplate = await GetMessageTemplate("AuctionExpired.StoreOwnerNotification", "");
             if (messageTemplate == null)

src/Core/Grand.Infrastructure/Caching/Constants/CommonCacheKey.cs

@@ -155,6 +155,19 @@ public static partial class CacheKey
     /// </remarks>
     public static string STORES_BY_ID_KEY => "Grand.stores.id-{0}";
 
+    /// <summary>
+    ///     Key for caching
+    /// </summary>
+    public static string STORES_FIRST_KEY => "Grand.stores.first";
+
+    /// <summary>
+    ///     Key for caching
+    /// </summary>
+    /// <remarks>
+    ///     {0} : host
+    /// </remarks>
+    public static string STORES_BY_HOST_KEY => "Grand.stores.host-{0}";
+
     #endregion
 
     #region Tax

src/Tests/Grand.Business.Common.Tests/Services/Stores/StoreServiceTests.cs

@@ -2,6 +2,7 @@
 using Grand.Data;
 using Grand.Domain.Stores;
 using Grand.Infrastructure.Caching;
+using Grand.Infrastructure.Caching.Constants;
 using Grand.Infrastructure.Events;
 using MediatR;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
@@ -21,6 +22,8 @@ public class StoreServiceTests
     public void Init()
     {
         _cacheMock = new Mock<ICacheBase>();
+        _cacheMock.Setup(c => c.GetAsync(It.IsAny<string>(), It.IsAny<Func<Task<Store>>>()))
+            .Returns<string, Func<Task<Store>>>((_, acquire) => acquire());
         _mediatorMock = new Mock<IMediator>();
         _repository = new Mock<IRepository<Store>>();
         _service = new StoreService(_cacheMock.Object, _repository.Object, _mediatorMock.Object);
@@ -47,8 +50,7 @@ public async Task UpdateStore_ValidArgument_InvokeExpectedMethods()
     [TestMethod]
     public async Task DeleteStore_ValidArgument_InvokeExpectedMethods()
     {
-        _cacheMock.Setup(c => c.GetAsync(It.IsAny<string>(), It.IsAny<Func<Task<List<Store>>>>()))
-            .Returns(Task.FromResult(new List<Store> { new(), new() }));
+        _repository.Setup(c => c.Table).Returns(new List<Store> { new(), new() }.AsQueryable());
         await _service.DeleteStore(new Store());
         _repository.Verify(c => c.DeleteAsync(It.IsAny<Store>()), Times.Once);
         _mediatorMock.Verify(c => c.Publish(It.IsAny<EntityDeleted<Store>>(), default), Times.Once);
@@ -59,8 +61,7 @@ public async Task DeleteStore_ValidArgument_InvokeExpectedMethods()
     public void DeleteStore_OnlyOneStore_ThrowException()
     {
         //can not remove store if it is only one 
-        _cacheMock.Setup(c => c.GetAsync(It.IsAny<string>(), It.IsAny<Func<Task<List<Store>>>>()))
-            .Returns(Task.FromResult(new List<Store> { new() }));
+        _repository.Setup(c => c.Table).Returns(new List<Store> { new() }.AsQueryable());
         Assert.ThrowsExactlyAsync<Exception>(async () => await _service.DeleteStore(new Store()));
     }
 
@@ -80,16 +81,15 @@ public async Task GetStoreByHost_MatchingHost_ReturnsMatchingStore()
             new DomainHost { HostName = "store2.com", Url = "http://store2.com", Primary = true }
         };
 
-        var stores = new List<Store> { store1, store2 };
-
-        _cacheMock.Setup(c => c.GetAsync(It.IsAny<string>(), It.IsAny<Func<Task<List<Store>>>>()))
-            .Returns(Task.FromResult(stores));
+        _repository.Setup(c => c.Table).Returns(new List<Store> { store1, store2 }.AsQueryable());
 
         // Act
         var result = await _service.GetStoreByHost("store1.com");
 
         // Assert
         Assert.AreEqual(store1, result);
+        _cacheMock.Verify(c => c.GetAsync(string.Format(CacheKey.STORES_BY_HOST_KEY, "store1.com"),
+            It.IsAny<Func<Task<Store>>>()), Times.Once);
     }
 
     [TestMethod]
@@ -108,15 +108,25 @@ public async Task GetStoreByHost_NoMatchingHost_ReturnsNullStore()
             new DomainHost { HostName = "store2.com", Url = "http://store2.com", Primary = true }
         };
 
-        var stores = new List<Store> { store1, store2 };
-
-        _cacheMock.Setup(c => c.GetAsync(It.IsAny<string>(), It.IsAny<Func<Task<List<Store>>>>()))
-            .Returns(Task.FromResult(stores));
+        _repository.Setup(c => c.Table).Returns(new List<Store> { store1, store2 }.AsQueryable());
 
         // Act - host not found in any DomainHost
         var result = await _service.GetStoreByHost("nonexisting.com");
 
         // Assert - returns first store
         Assert.IsNull(result);
     }
+
+    [TestMethod]
+    public async Task GetFirstStore_ReturnsStoreWithLowestDisplayOrder()
+    {
+        var store1 = new Store { DisplayOrder = 2 };
+        var store2 = new Store { DisplayOrder = 1 };
+        _repository.Setup(c => c.Table).Returns(new List<Store> { store1, store2 }.AsQueryable());
+
+        var result = await _service.GetFirstStore();
+
+        Assert.AreEqual(store2, result);
+        _cacheMock.Verify(c => c.GetAsync(CacheKey.STORES_FIRST_KEY, It.IsAny<Func<Task<Store>>>()), Times.Once);
+    }
 }

src/Web/Grand.Web.Common/StoreContextSetter.cs

@@ -58,7 +58,7 @@ protected async Task<Store> CurrentStore(string id = null)
         }
 
         // Fallback: return the first available store
-        return (await _storeService.GetAllStores()).FirstOrDefault();
+        return await _storeService.GetFirstStore();
     }
 
     /// <summary>
@@ -89,4 +89,3 @@ private sealed class CurrentStoreContext : IStoreContext
     }
 }
 
-

src/Web/Grand.Web.Common/WorkContextSetter.cs

@@ -440,7 +440,7 @@ protected async Task<Store> CurrentStore(string id = null)
         if (!string.IsNullOrEmpty(id))
             return await _storeService.GetStoreById(id);
 
-        return (await _storeService.GetAllStores()).FirstOrDefault();
+        return await _storeService.GetFirstStore();
     }
 
     private sealed class CurrentWorkContext : IWorkContext