Remove RequiresPreviewFeatures attribute for Lambda Response Streaming

.autover/changes/9e75413c-9cb6-4521-aaca-09b557fff2b3.json

@@ -0,0 +1,50 @@
+{
+  "Projects": [
+    {
+      "Name": "Amazon.Lambda.Core",
+      "Type": "Minor",
+      "ChangelogMessages": [
+        "Lambda response streaming is now available as GA. The RequiresPreviewFeatures attribute has been removed",
+		"The LambdaLogger.ConfigureStructuredLogging API has been deployed to the managed runtime. The RequiresPreviewFeatures attribute has been removed"
+      ]
+    },
+	{
+      "Name": "Amazon.Lambda.Annotations",
+      "Type": "Minor",
+      "ChangelogMessages": [
+        "Updated Amazon.Lambda.Core dependency to include Lambda Response Streaming support."
+      ]		
+	},
+	{
+      "Name": "Amazon.Lambda.AspNetCoreServer",
+      "Type": "Minor",
+      "ChangelogMessages": [
+		"Removed RequiresPreviewFeatures attribute for Lambda Response Streaming.",
+        "Updated Amazon.Lambda.Core dependency to include Lambda Response Streaming support.",
+		"Updated the base class AbstractAspNetCoreFunction to implement IDisposable. This is mostly needed for unit tests. In the Lambda environment there will only be one instance of AbstractAspNetCoreFunction subclass created."
+      ]		
+	},
+	{
+      "Name": "Amazon.Lambda.AspNetCoreServer.Hosting",
+      "Type": "Minor",
+      "ChangelogMessages": [
+		"Removed RequiresPreviewFeatures attribute for Lambda Response Streaming.",
+        "Updated Amazon.Lambda.Core dependency to include Lambda Response Streaming support."
+      ]		
+	},
+	{
+      "Name": "Amazon.Lambda.PowerShellHost",
+      "Type": "Minor",
+      "ChangelogMessages": [
+        "Updated Amazon.Lambda.Core dependency to include Lambda Response Streaming support."
+      ]		
+	},
+	{
+      "Name": "Amazon.Lambda.RuntimeSupport",
+      "Type": "Minor",
+      "ChangelogMessages": [
+        "Updated Amazon.Lambda.Core dependency to include Lambda Response Streaming support."
+      ]		
+	}
+  ]
+}

Libraries/src/Amazon.Lambda.AspNetCoreServer.Hosting/HostingOptions.cs

@@ -39,7 +39,6 @@ public class HostingOptions
     /// <c>FunctionHandlerAsync</c> writes directly to the Lambda response stream and
     /// returns <c>null</c>. Requires net8.0 or later.
     /// </summary>
-    [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
     public bool EnableResponseStreaming { get; set; } = false;
 
     /// <summary>

Libraries/src/Amazon.Lambda.AspNetCoreServer/APIGatewayHttpApiV2ProxyFunction.cs

@@ -59,7 +59,6 @@ private protected override void InternalCustomResponseExceptionHandling(APIGatew
         /// instead of <c>multiValueHeaders</c>. API Gateway HTTP API v2 expects the <c>headers</c>
         /// format; using <c>multiValueHeaders</c> causes a 500 Internal Server Error.
         /// </summary>
-        [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
         protected override Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude BuildStreamingPrelude(IHttpResponseFeature responseFeature)
         {
             var prelude = new Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude

Libraries/src/Amazon.Lambda.AspNetCoreServer/APIGatewayProxyFunction.cs

@@ -113,7 +113,6 @@ private protected override void InternalCustomResponseExceptionHandling(APIGatew
         /// </summary>
         /// <param name="responseFeature">The ASP.NET Core response feature for the current invocation.</param>
         /// <returns>A populated <see cref="Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude"/>.</returns>
-        [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
         protected override Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude BuildStreamingPrelude(IHttpResponseFeature responseFeature)
         {
             var prelude = new Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude

Libraries/src/Amazon.Lambda.AspNetCoreServer/AbstractAspNetCoreFunction.cs

@@ -24,12 +24,6 @@ namespace Amazon.Lambda.AspNetCoreServer
     /// </summary>
     public abstract class AbstractAspNetCoreFunction
     {
-        internal const string ParameterizedPreviewMessage =
-            "Response streaming is in preview till a new version of .NET Lambda runtime client that supports response streaming " +
-            "has been deployed to the .NET Lambda managed runtime. Till deployment has been made the feature can be used by deploying as an " +
-            "executable including the latest version of Amazon.Lambda.RuntimeSupport and setting the \"EnablePreviewFeatures\" in the Lambda " +
-            "project file to \"true\"";
-
         /// <summary>
         /// Key to access the ILambdaContext object from the HttpContext.Items collection.
         /// </summary>
@@ -47,13 +41,21 @@ public abstract class AbstractAspNetCoreFunction
     /// </summary>
     /// <typeparam name="TREQUEST"></typeparam>
     /// <typeparam name="TRESPONSE"></typeparam>
-    public abstract class AbstractAspNetCoreFunction<TREQUEST, TRESPONSE> : AbstractAspNetCoreFunction
+    public abstract class AbstractAspNetCoreFunction<TREQUEST, TRESPONSE> : AbstractAspNetCoreFunction, IDisposable
     {
         private protected IServiceProvider _hostServices;
         private protected LambdaServer _server;
         private protected ILogger _logger;
         private protected StartupMode _startupMode;
 
+        // The IHost created and owned by this instance in Start(). Retained so it can be disposed,
+        // releasing resources such as the configuration file-change watchers (inotify instances on Linux)
+        // that Host.CreateDefaultBuilder registers. Null when the function is constructed from an
+        // externally-owned IServiceProvider, in which case this instance does not own the host.
+        private IHost _host;
+
+        private bool _disposed;
+
         // Defines a mapping from registered content types to the response encoding format
         // which dictates what transformations should be applied before returning response content
         private readonly Dictionary<string, ResponseContentEncoding> _responseContentEncodingForContentType = new Dictionary<string, ResponseContentEncoding>
@@ -206,7 +208,6 @@ public void RegisterResponseContentEncodingForContentEncoding(string contentEnco
         /// buffering it and returning a typed response object (which will be <c>null</c>).
         /// Requires net8.0 or later.
         /// </summary>
-        [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
         public virtual bool EnableResponseStreaming { get; set; } = false;
 
 
@@ -364,6 +365,7 @@ protected void Start()
             });
 
             var host = builder.Build();
+            _host = host;
             PostCreateHost(host);
 
             host.Start();
@@ -678,7 +680,6 @@ protected virtual void PostMarshallResponseFeature(IHttpResponseFeature aspNetCo
         /// </summary>
         /// <param name="responseFeature">The ASP.NET Core response feature for the current invocation.</param>
         /// <returns>A populated <see cref="Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude"/>.</returns>
-        [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
         protected abstract Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude BuildStreamingPrelude(IHttpResponseFeature responseFeature);
 
         /// <summary>
@@ -689,7 +690,6 @@ protected virtual void PostMarshallResponseFeature(IHttpResponseFeature aspNetCo
         /// </summary>
         /// <param name="prelude">The HTTP response prelude containing status code and headers.</param>
         /// <returns>A writable <see cref="System.IO.Stream"/> for the response body.</returns>
-        [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
         protected virtual System.IO.Stream CreateLambdaResponseStream(
             Amazon.Lambda.Core.ResponseStreaming.HttpResponseStreamPrelude prelude)
         {
@@ -701,7 +701,6 @@ protected virtual System.IO.Stream CreateLambdaResponseStream(
         /// <see cref="EnableResponseStreaming"/> is <c>true</c>. Writes the response directly to a
         /// <see cref="Amazon.Lambda.Core.ResponseStreaming.LambdaResponseStream"/>.
         /// </summary>
-        [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
         private async Task ExecuteStreamingRequestAsync(InvokeFeatures features)
         {
             var responseFeature = (IHttpResponseFeature)features;
@@ -824,5 +823,37 @@ private async Task RunPipelineAsync(object context, InvokeFeatures features)
                 throw;
             }
         }
+
+        /// <summary>
+        /// Disposes the IHost created and owned by this instance in <see cref="Start"/>, releasing
+        /// resources it holds such as the configuration file-change watchers (inotify instances on Linux)
+        /// registered by Host.CreateDefaultBuilder. When the function was constructed from an
+        /// externally-owned IServiceProvider this instance does not own a host and disposal is a no-op.
+        /// </summary>
+        /// <param name="disposing"><c>true</c> when called from <see cref="Dispose()"/>.</param>
+        protected virtual void Dispose(bool disposing)
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            if (disposing)
+            {
+                _host?.Dispose();
+                _host = null;
+            }
+
+            _disposed = true;
+        }
+
+        /// <summary>
+        /// Disposes the resources owned by this function, including the IHost created in <see cref="Start"/>.
+        /// </summary>
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
     }
 }

Libraries/src/Amazon.Lambda.AspNetCoreServer/ApplicationLoadBalancerFunction.cs

@@ -225,7 +225,6 @@ private protected override void InternalCustomResponseExceptionHandling(Applicat
         }
 
         /// <inheritdoc/>
-        [System.Runtime.Versioning.RequiresPreviewFeatures(ParameterizedPreviewMessage)]
         protected override HttpResponseStreamPrelude BuildStreamingPrelude(IHttpResponseFeature responseFeature) => throw new NotImplementedException();
 
         private string GetSingleHeaderValue(ApplicationLoadBalancerRequest request, string headerName)

Libraries/src/Amazon.Lambda.AspNetCoreServer/Internal/StreamingResponseBodyFeature.cs

@@ -3,7 +3,6 @@
 using System;
 using System.IO;
 using System.IO.Pipelines;
-using System.Runtime.Versioning;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -20,7 +19,6 @@ namespace Amazon.Lambda.AspNetCoreServer.Internal
     /// <see cref="MemoryStream"/>; after <see cref="StartAsync"/> all writes go directly to the
     /// <see cref="LambdaResponseStream"/> obtained from the stream opener delegate.
     /// </summary>
-    [RequiresPreviewFeatures(AbstractAspNetCoreFunction.ParameterizedPreviewMessage)]
     internal class StreamingResponseBodyFeature : IHttpResponseBodyFeature
     {
         private readonly ILogger _logger;

Libraries/src/Amazon.Lambda.Core/LambdaLogger.cs

@@ -1,6 +1,7 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
 using System;
-using System.Reflection.Emit;
-using System.Runtime.Versioning;
 using System.Text;
 
 namespace Amazon.Lambda.Core
@@ -139,7 +140,6 @@ public static void Log(string level, Exception exception, string message, params
         /// When structured logging is enabled this method will allow overriding the default configuration the Lambda runtime uses for structured logging.
         /// </summary>
         /// <param name="options">The options to use for configuring structured logging.</param>
-        [RequiresPreviewFeatures("This method is in preview until the latest changes of the .NET Lambda runtime client have been deployed to the Lambda managed runtimes")]
         public static void ConfigureStructuredLogging(StructuredLoggingOptions options) => _configureStructuredLoggingAction(options);
 
         internal static void SetConfigureStructuredLoggingAction(Action<StructuredLoggingOptions> configureStructuredLoggingAction)

Libraries/src/Amazon.Lambda.Core/ResponseStreaming/HttpResponseStreamPrelude.cs

@@ -4,7 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Net;
-using System.Runtime.Versioning;
 using System.Text.Json;
 
 namespace Amazon.Lambda.Core.ResponseStreaming
@@ -15,7 +14,6 @@ namespace Amazon.Lambda.Core.ResponseStreaming
     /// headers, and cookies for the response. The prelude must be sent as the first chunk of the response stream, followed by the response body chunks.
     /// This allows you to set the status code and headers for the response before sending any of the response body.
     /// </summary>
-    [RequiresPreviewFeatures(LambdaResponseStreamFactory.PreviewMessage)]
     public class HttpResponseStreamPrelude
     {
         /// <summary>

Libraries/src/Amazon.Lambda.Core/ResponseStreaming/LambdaResponseStream.cs

@@ -4,7 +4,6 @@
 
 using System;
 using System.IO;
-using System.Runtime.Versioning;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -15,7 +14,6 @@ namespace Amazon.Lambda.Core.ResponseStreaming
     /// to the Lambda Runtime API. Returned by <see cref="LambdaResponseStreamFactory.CreateStream"/>.
     /// Integrates with standard .NET stream consumers such as <see cref="System.IO.StreamWriter"/>.
     /// </summary>
-    [RequiresPreviewFeatures(LambdaResponseStreamFactory.PreviewMessage)]
     public class LambdaResponseStream : Stream
     {
         private readonly ILambdaResponseStream _responseStream;

Libraries/src/Amazon.Lambda.Core/ResponseStreaming/LambdaResponseStreamFactory.cs

@@ -3,22 +3,14 @@
 #if NET8_0_OR_GREATER
 using System;
 using System.IO;
-using System.Runtime.Versioning;
 
 namespace Amazon.Lambda.Core.ResponseStreaming
 {
     /// <summary>
     /// Factory to create Lambda response streams for writing streaming responses in AWS Lambda functions. The created streams are write-only and non-seekable.
     /// </summary>
-    [RequiresPreviewFeatures(LambdaResponseStreamFactory.PreviewMessage)]
     public class LambdaResponseStreamFactory
     {
-        internal const string PreviewMessage =
-            "Response streaming is in preview till a new version of .NET Lambda runtime client that supports response streaming " +
-            "has been deployed to the .NET Lambda managed runtime. Till deployment has been made the feature can be used by deploying as an " +
-            "executable including the latest version of Amazon.Lambda.RuntimeSupport and setting the \"EnablePreviewFeatures\" in the Lambda " +
-            "project file to \"true\"";
-
         internal const string UninitializedFactoryMessage =
             "LambdaResponseStreamFactory is not initialized. This is caused by mismatch versions of Amazon.Lambda.Core and Amazon.Lambda.RuntimeSupport. " +
             "Update both packages to the current version to address the issue.";

Libraries/test/Amazon.Lambda.AspNetCoreServer.Hosting.Tests/Amazon.Lambda.AspNetCoreServer.Hosting.Tests.csproj

@@ -11,6 +11,8 @@
     <GenerateAssemblyCompanyAttribute>false</GenerateAssemblyCompanyAttribute>
     <GenerateAssemblyProductAttribute>false</GenerateAssemblyProductAttribute>
     <NoWarn>1701;1702;1705;CS0618;CS1591</NoWarn>
+    <!-- Applied automatically by "dotnet test" so DOTNET_USE_POLLING_FILE_WATCHER is set before the test host starts. See test.runsettings. -->
+    <RunSettingsFilePath>$(MSBuildProjectDirectory)\test.runsettings</RunSettingsFilePath>
   </PropertyGroup>
 
   <ItemGroup>

Libraries/test/Amazon.Lambda.AspNetCoreServer.Hosting.Tests/ResponseStreamingHostingTests.cs

@@ -1,8 +1,6 @@
 // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0
 
-
-using System.Runtime.Versioning;
 using Amazon.Lambda.AspNetCoreServer.Hosting.Internal;
 using Amazon.Lambda.AspNetCoreServer.Test;
 using Amazon.Lambda.Core;
@@ -16,7 +14,6 @@ namespace Amazon.Lambda.AspNetCoreServer.Hosting.Tests;
 /// <summary>
 /// Tests for response streaming integration in hosting (Requirement 10).
 /// </summary>
-[RequiresPreviewFeatures]
 public class ResponseStreamingHostingTests
 {
     [Fact]

Libraries/test/Amazon.Lambda.AspNetCoreServer.Hosting.Tests/ResponseStreamingPropertyTests.cs

@@ -1,8 +1,6 @@
 // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0
 
-using System.Runtime.Versioning;
-
 using Amazon.Lambda.AspNetCoreServer.Hosting.Internal;
 using Amazon.Lambda.Core;
 using Amazon.Lambda.RuntimeSupport;
@@ -14,7 +12,6 @@
 
 namespace Amazon.Lambda.AspNetCoreServer.Hosting.Tests;
 
-[RequiresPreviewFeatures]
 public class ResponseStreamingPropertyTests
 {
     private static IServiceProvider BuildServiceProvider(HostingOptions hostingOptions)

Libraries/test/Amazon.Lambda.AspNetCoreServer.Hosting.Tests/ServiceCollectionExtensionsTests.cs

@@ -135,26 +135,6 @@ public void AddAWSLambdaHosting_ApplicationLoadBalancer_RegistersHostingOptions(
         Assert.True(hostingOptions.ContentTypeEncodings.ContainsKey("image/png"));
     }
 
-    [Fact]
-    public void AddAWSLambdaHosting_NotInLambda_DoesNotRegisterHostingOptions()
-    {
-        // Arrange
-        var services = new ServiceCollection();
-        // No AWS_LAMBDA_FUNCTION_NAME environment variable set
-
-        // Act
-        services.AddAWSLambdaHosting(LambdaEventSource.HttpApi, options =>
-        {
-            options.DefaultResponseContentEncoding = ResponseContentEncoding.Base64;
-        });
-
-        var serviceProvider = services.BuildServiceProvider();
-
-        // Assert
-        var hostingOptions = serviceProvider.GetService<HostingOptions>();
-        Assert.Null(hostingOptions);
-    }
-
     [Fact]
     public void AddAWSLambdaHosting_ConfigurationIsApplied()
     {

Libraries/test/Amazon.Lambda.AspNetCoreServer.Hosting.Tests/test.runsettings

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RunSettings>
+  <RunConfiguration>
+    <!--
+      Force ASP.NET Core / Microsoft.Extensions configuration to use a polling file watcher instead of
+      the OS file-system watcher. On Linux the OS watcher is backed by inotify, and each host built via
+      Host.CreateDefaultBuilder / WebApplication registers several reloadOnChange watchers on appsettings*.json.
+      These tests construct many ASP.NET Core hosts and xUnit runs test classes in parallel; when this assembly
+      runs alongside Amazon.Lambda.AspNetCoreServer.Test in a single solution-wide test run, the concurrent number
+      of inotify instances exceeds the per-user limit (fs.inotify.max_user_instances, 128 by default on the CI
+      hosts), producing "The configured user limit (128) on the number of inotify instances has been reached".
+
+      The polling watcher uses a timer instead of inotify, so no inotify instances are consumed. VSTest sets
+      these variables before the test host process starts, so they take effect before any host is built.
+    -->
+    <EnvironmentVariables>
+      <DOTNET_USE_POLLING_FILE_WATCHER>1</DOTNET_USE_POLLING_FILE_WATCHER>
+    </EnvironmentVariables>
+  </RunConfiguration>
+</RunSettings>

Libraries/test/Amazon.Lambda.AspNetCoreServer.Test/Amazon.Lambda.AspNetCoreServer.Test.csproj

@@ -12,6 +12,8 @@
     <GenerateAssemblyCompanyAttribute>false</GenerateAssemblyCompanyAttribute>
     <GenerateAssemblyProductAttribute>false</GenerateAssemblyProductAttribute>
     <NoWarn>1701;1702;1705;CS0618;CS1591</NoWarn>
+    <!-- Applied automatically by "dotnet test" so DOTNET_USE_POLLING_FILE_WATCHER is set before the test host starts. See test.runsettings. -->
+    <RunSettingsFilePath>$(MSBuildProjectDirectory)\test.runsettings</RunSettingsFilePath>
   </PropertyGroup>
 
   <ItemGroup>