test: Use Parallel.ForEachAsync

Author: xC0dex

src/OpenApi/src/Services/OpenApiDocumentService.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Collections.Concurrent;
 using System.Collections.Frozen;
 using System.ComponentModel;
 using System.ComponentModel.DataAnnotations;
@@ -46,7 +47,7 @@ internal sealed class OpenApiDocumentService(
     /// are unique within the lifetime of an application and serve as helpful associators between
     /// operations, API descriptions, and their respective transformer contexts.
     /// </summary>
-    private readonly Dictionary<string, OpenApiOperationTransformerContext> _operationTransformerContextCache = new();
+    private readonly ConcurrentDictionary<string, OpenApiOperationTransformerContext> _operationTransformerContextCache = new();
     private static readonly ApiResponseType _defaultApiResponseType = new() { StatusCode = StatusCodes.Status200OK };
 
     private static readonly FrozenSet<string> _disallowedHeaderParameters = new[] { HeaderNames.Accept, HeaderNames.Authorization, HeaderNames.ContentType }.ToFrozenSet(StringComparer.OrdinalIgnoreCase);

src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/OpenApiDocumentConcurrentRequestTests.cs

@@ -13,20 +13,14 @@ public async Task MapOpenApi_HandlesConcurrentRequests()
     {
         // Arrange
         var client = fixture.CreateClient();
-        var requests = new List<Task<HttpResponseMessage>>
-        {
-            client.GetAsync("/openapi/v1.json"),
-            client.GetAsync("/openapi/v1.json"),
-            client.GetAsync("/openapi/v1.json")
-        };
 
         // Act
-        var results = await Task.WhenAll(requests);
-
-        // Assert
-        foreach (var result in results)
+        await Parallel.ForAsync(0, 150, async (_, ctx) =>
         {
-            Assert.Equal(HttpStatusCode.OK, result.StatusCode);
-        }
+            var response = await client.GetAsync("/openapi/v1.json", ctx);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+        });
     }
 }