Update response compression docs and add test (#1208)

Author: Shane32

README.md

@@ -675,7 +675,7 @@ follows:
 builder.Services.AddResponseCompression(options =>
 {
     options.EnableForHttps = true; // may lead to CRIME and BREACH attacks
-    options.MimeTypes = new[] { "application/json", "application/graphql-response+json" };
+    options.MimeTypes = ResponseCompressionDefaults.MimeTypes.Append("application/graphql-response+json");
 })
 
 // place this first/early in the pipeline
@@ -687,7 +687,7 @@ added to the `MimeTypes` option.  You may choose to enable other content types a
 
 Please note that enabling response compression over HTTPS can lead to CRIME and BREACH
 attacks.  These side-channel attacks typically affects sites that rely on cookies for
-authentication.  Please read [this](https://docs.microsoft.com/en-us/aspnet/core/performance/response-compression?view=aspnetcore-6.0)
+authentication.  Please read [this](https://docs.microsoft.com/en-us/aspnet/core/performance/response-compression)
 and [this](http://www.breachattack.com/#howitworks) for more details.
 
 ### ASP.NET Core 2.1 / .NET Framework 4.8

tests/Transports.AspNetCore.Tests/Middleware/CompressionTests.cs

@@ -0,0 +1,67 @@
+#if !NETCOREAPP2_1 && !NET48
+
+using System.IO.Compression;
+using System.Net.Http.Headers;
+using Microsoft.AspNetCore.ResponseCompression;
+
+namespace Tests.Middleware;
+
+public class CompressionTests
+{
+    [Fact]
+    public async Task ResponseCompression_ShouldCompressGraphQLResponse()
+    {
+        // Arrange
+        var hostBuilder = new WebHostBuilder();
+        hostBuilder.ConfigureServices(services =>
+        {
+            services.AddGraphQL(b => b
+                .AddAutoSchema<Query>()
+                .AddSystemTextJson());
+            services.AddRouting();
+            services.AddResponseCompression(options =>
+            {
+                options.EnableForHttps = true;
+                options.MimeTypes = ResponseCompressionDefaults.MimeTypes.Append("application/graphql-response+json");
+            });
+        });
+        hostBuilder.Configure(app =>
+        {
+            app.UseResponseCompression();
+            app.UseGraphQL();
+        });
+
+        using var server = new TestServer(hostBuilder);
+        using var client = server.CreateClient();
+
+        // Act
+        using var request = new HttpRequestMessage(HttpMethod.Post, "/graphql");
+        var content = new StringContent("{hello}");
+        content.Headers.ContentType = new MediaTypeHeaderValue("application/graphql");
+        request.Content = content;
+        request.Headers.Add("Accept-Encoding", "gzip");
+
+        using var response = await client.SendAsync(request);
+
+        // Assert
+        response.EnsureSuccessStatusCode();
+
+        // Check if response is compressed
+        response.Content.Headers.ContentEncoding.ShouldContain("gzip");
+
+        // Decompress and verify content
+        using var responseStream = await response.Content.ReadAsStreamAsync();
+        using var decompressionStream = new GZipStream(responseStream, CompressionMode.Decompress);
+        using var reader = new StreamReader(decompressionStream);
+        var decompressedContent = await reader.ReadToEndAsync();
+
+        decompressedContent.ShouldBe("""{"data":{"hello":"world"}}""");
+    }
+
+    public class Query
+    {
+        public static string Hello => "world";
+    }
+}
+
+#endif