Fix key-value mapping in GetOrAddMany and add tests

Refactored GetOrAddMany and GetOrAddManyAsync in DistributedCache to ensure returned key-value pairs are correctly mapped by key, regardless of order from the factory. Added unit tests to verify correct mapping and concurrency behavior.

framework/src/Volo.Abp.Caching/Volo/Abp/Caching/DistributedCache.cs

@@ -19,7 +19,7 @@ namespace Volo.Abp.Caching;
 /// Represents a distributed cache of <typeparamref name="TCacheItem" /> type.
 /// </summary>
 /// <typeparam name="TCacheItem">The type of cache item being cached.</typeparam>
-public class DistributedCache<TCacheItem> : 
+public class DistributedCache<TCacheItem> :
     IDistributedCache<TCacheItem>
     where TCacheItem : class
 {
@@ -683,35 +683,30 @@ public class DistributedCache<TCacheItem, TCacheKey> : IDistributedCache<TCacheI
             result = cachedValues.Concat(ToCacheItems(cachedBytes, readKeys)).ToArray();
         }
 
-        if (result.All(x => x.Value != null))
-        {
-            return result!;
-        }
+        var resultMap = result
+            .Where(x => x.Value != null)
+            .ToDictionary(x => x.Key, x => x.Value);
 
-        var missingKeys = new List<TCacheKey>();
-        var missingValuesIndex = new List<int>();
-        for (var i = 0; i < keyArray.Length; i++)
+        if (resultMap.Count == keyArray.Length)
         {
-            if (result[i].Value != null)
-            {
-                continue;
-            }
-
-            missingKeys.Add(keyArray[i]);
-            missingValuesIndex.Add(i);
+            return keyArray
+                .Select(key => new KeyValuePair<TCacheKey, TCacheItem?>(key, resultMap[key]))
+                .ToArray();
         }
 
+        var missingKeys = keyArray.Where(key => !resultMap.ContainsKey(key)).ToList();
         var missingValues = factory.Invoke(missingKeys).ToArray();
-        var valueQueue = new Queue<KeyValuePair<TCacheKey, TCacheItem>>(missingValues);
 
         SetMany(missingValues, optionsFactory?.Invoke(), hideErrors, considerUow);
 
-        foreach (var index in missingValuesIndex)
+        foreach (var pair in missingValues)
         {
-            result[index] = valueQueue.Dequeue()!;
+            resultMap[pair.Key] = pair.Value;
         }
 
-        return result;
+        return keyArray
+            .Select(key => new KeyValuePair<TCacheKey, TCacheItem?>(key, resultMap.GetOrDefault(key)))
+            .ToArray();
     }
 
 
@@ -779,35 +774,30 @@ public class DistributedCache<TCacheItem, TCacheKey> : IDistributedCache<TCacheI
             result = cachedValues.Concat(ToCacheItems(cachedBytes, readKeys)).ToArray();
         }
 
-        if (result.All(x => x.Value != null))
-        {
-            return result;
-        }
+        var resultMap = result
+            .Where(x => x.Value != null)
+            .ToDictionary(x => x.Key, x => x.Value);
 
-        var missingKeys = new List<TCacheKey>();
-        var missingValuesIndex = new List<int>();
-        for (var i = 0; i < keyArray.Length; i++)
+        if (resultMap.Count == keyArray.Length)
         {
-            if (result[i].Value != null)
-            {
-                continue;
-            }
-
-            missingKeys.Add(keyArray[i]);
-            missingValuesIndex.Add(i);
+            return keyArray
+                .Select(key => new KeyValuePair<TCacheKey, TCacheItem?>(key, resultMap[key]))
+                .ToArray();
         }
 
+        var missingKeys = keyArray.Where(key => !resultMap.ContainsKey(key)).ToList();
         var missingValues = (await factory.Invoke(missingKeys)).ToArray();
-        var valueQueue = new Queue<KeyValuePair<TCacheKey, TCacheItem>>(missingValues);
 
         await SetManyAsync(missingValues, optionsFactory?.Invoke(), hideErrors, considerUow, token);
 
-        foreach (var index in missingValuesIndex)
+        foreach (var pair in missingValues)
         {
-            result[index] = valueQueue.Dequeue()!;
+            resultMap[pair.Key] = pair.Value;
         }
 
-        return result;
+        return keyArray
+            .Select(key => new KeyValuePair<TCacheKey, TCacheItem?>(key, resultMap.GetOrDefault(key)))
+            .ToArray();
     }
 
     /// <summary>

framework/test/Volo.Abp.Caching.Tests/Volo/Abp/Caching/DistributedCache_Tests.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
 using Shouldly;
 using Volo.Abp.Testing;
@@ -751,6 +752,74 @@ public class DistributedCache_Tests : AbpIntegratedTest<AbpCachingTestModule>
         cacheValue[1].Value.Name.ShouldBe("jack");
     }
 
+    [Fact]
+    public async Task GetOrAddManyAsync_Should_Return_Values_By_Key_With_Uow()
+    {
+        var key1 = "testkey";
+        var key2 = "testkey2";
+        var keys = new[] { key1, key2 };
+
+        using (GetRequiredService<IUnitOfWorkManager>().Begin())
+        {
+            var personCache = GetRequiredService<IDistributedCache<PersonCacheItem>>();
+
+            await personCache.SetAsync(key2, new PersonCacheItem("cached"), considerUow: true);
+
+            var result = await personCache.GetOrAddManyAsync(keys, missingKeys =>
+            {
+                missingKeys.ToArray().ShouldBe(new[] { key1 });
+                return Task.FromResult(new List<KeyValuePair<string, PersonCacheItem>>
+                {
+                    new(key1, new PersonCacheItem("factory"))
+                });
+            }, considerUow: true);
+
+            result.Length.ShouldBe(2);
+            result[0].Key.ShouldBe(key1);
+            result[0].Value.ShouldNotBeNull();
+            result[0].Value.Name.ShouldBe("factory");
+            result[1].Key.ShouldBe(key2);
+            result[1].Value.ShouldNotBeNull();
+            result[1].Value.Name.ShouldBe("cached");
+        }
+    }
+
+    [Fact]
+    public async Task GetOrAddManyAsync_Should_Map_By_Key_Under_Concurrency()
+    {
+        var key1 = "testkey";
+        var key2 = "testkey2";
+        var keys = new[] { key1, key2 };
+
+        var personCache = GetRequiredService<IDistributedCache<PersonCacheItem>>();
+
+        async Task<List<KeyValuePair<string, PersonCacheItem>>> Factory(IEnumerable<string> missingKeys)
+        {
+            await Task.Yield();
+
+            return missingKeys
+                .Reverse()
+                .Select(x => new KeyValuePair<string, PersonCacheItem>(x, new PersonCacheItem(x == key1 ? "v1" : "v2")))
+                .ToList();
+        }
+
+        var task1 = personCache.GetOrAddManyAsync(keys, Factory);
+        var task2 = personCache.GetOrAddManyAsync(keys, Factory);
+
+        var results = await Task.WhenAll(task1, task2);
+
+        foreach (var result in results)
+        {
+            result.Length.ShouldBe(2);
+
+            result[0].Key.ShouldBe(key1);
+            result[0].Value!.Name.ShouldBe("v1");
+
+            result[1].Key.ShouldBe(key2);
+            result[1].Value!.Name.ShouldBe("v2");
+        }
+    }
+
     [Fact]
     public async Task Cache_Should_Only_Available_In_Uow_For_GetOrAddManyAsync()
     {