Azure Functions isolated process

src/Directory.Build.props

@@ -45,8 +45,11 @@
     <TestTargetFrameworks Condition="'$(IsMacOsArm)' == 'true'">net7.0; net6.0</TestTargetFrameworks>
     <AspNetTargetFrameworks Condition="'$(IsMacOsArm)' != 'true'">net7.0; net6.0; net5.0; netcoreapp3.1</AspNetTargetFrameworks>
     <AspNetTargetFrameworks Condition="'$(IsMacOsArm)' == 'true'">net7.0; net6.0</AspNetTargetFrameworks>
-    <AzfTargetFrameworks Condition="'$(IsMacOsArm)' != 'true'">net6.0; net5.0; netcoreapp3.1</AzfTargetFrameworks>
-    <AzfTargetFrameworks Condition="'$(IsMacOsArm)' == 'true'">net6.0</AzfTargetFrameworks>
+    <AzfTargetFrameworks Condition="'$(IsMacOsArm)' != 'true'">net7.0; net6.0; net5.0; netcoreapp3.1</AzfTargetFrameworks>
+    <AzfTargetFrameworks Condition="'$(IsMacOsArm)' == 'true'">net7.0; net6.0</AzfTargetFrameworks>
+    <!-- Azure Functions Isolated Process does not support netcoreapp3.1 (on net5.0+) -->
+    <AzfIsoProcTargetFrameworks Condition="'$(IsMacOsArm)' != 'true'">net7.0; net6.0; net5.0;</AzfIsoProcTargetFrameworks>
+    <AzfIsoProcTargetFrameworks Condition="'$(IsMacOsArm)' == 'true'">net7.0; net6.0</AzfIsoProcTargetFrameworks>
     <SourceGenTargetFrameworks>net7.0; net6.0; netstandard2.0</SourceGenTargetFrameworks>
   </PropertyGroup>
 

src/HotChocolate/AzureFunctions/Directory.Build.props

@@ -3,6 +3,7 @@
 
   <PropertyGroup>
     <TargetFrameworks>$(AzfTargetFrameworks)</TargetFrameworks>
+    <TargetFrameworks Condition="$(MSBuildProjectName.Contains('Isolated'))">$(AzfIsoProcTargetFrameworks)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
 

src/HotChocolate/AzureFunctions/src/HotChocolate.AzureFunctions.IsolatedProcess/Extensions/GraphQLRequestExecutorExtensions.cs

@@ -0,0 +1,52 @@
+using Microsoft.Azure.Functions.Worker.Http;
+
+namespace HotChocolate.AzureFunctions.IsolatedProcess;
+
+public static class GraphQLRequestExecutorExtensions
+{
+    public static Task<HttpResponseData> ExecuteAsync(
+        this IGraphQLRequestExecutor graphqlRequestExecutor,
+        HttpRequestData httpRequestData)
+    {
+        if (graphqlRequestExecutor is null)
+        {
+            throw new ArgumentNullException(nameof(graphqlRequestExecutor));
+        }
+
+        if (httpRequestData is null)
+        {
+            throw new ArgumentNullException(nameof(httpRequestData));
+        }
+
+        // Factored out Async logic to Address SonarCloud concern for exceptions in Async flow ...
+        return ExecuteGraphQLRequestInternalAsync(graphqlRequestExecutor, httpRequestData);
+    }
+
+    private static async Task<HttpResponseData> ExecuteGraphQLRequestInternalAsync(
+        IGraphQLRequestExecutor graphqlRequestExecutor,
+        HttpRequestData httpRequestData)
+    {
+        // Adapt the Isolated Process HttpRequestData to the HttpContext needed by
+        // HotChocolate and execute the Pipeline...
+        // NOTE: This must be disposed of properly to ensure our request/response
+        // resources are managed efficiently.
+        using var shim =
+            await HttpContextShim.CreateHttpContextAsync(httpRequestData).ConfigureAwait(false);
+
+        // Isolated Process doesn't natively support HttpContext so we must manually enable
+        // support for HttpContext injection within HotChocolate (e.g. into Resolvers) for
+        // low-level access.
+        httpRequestData.SetCurrentHttpContext(shim.HttpContext);
+
+        // Now we can execute the request by marshalling the HttpContext into the
+        // DefaultGraphQLRequestExecutor which will handle pre & post processing as needed ...
+        // NOTE: We discard the result returned (likely an EmptyResult) as all content is already
+        // written to the HttpContext Response.
+        await graphqlRequestExecutor.ExecuteAsync(shim.HttpContext.Request).ConfigureAwait(false);
+
+        // Last, in the Isolated Process model we marshall all data back to the HttpResponseData
+        // model and return it to the AzureFunctions process ...
+        // Therefore we need to marshall the Response back to the Isolated Process model ...
+        return await shim.CreateHttpResponseDataAsync().ConfigureAwait(false);
+    }
+}

src/HotChocolate/AzureFunctions/src/HotChocolate.AzureFunctions.IsolatedProcess/Extensions/HotChocolateAzFuncIsolatedProcessHostBuilderExtensions.cs

@@ -0,0 +1,61 @@
+using HotChocolate.AzureFunctions;
+using HotChocolate.Execution.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+
+// ReSharper disable once CheckNamespace
+namespace Microsoft.Azure.Functions.Extensions.DependencyInjection;
+
+/// <summary>
+/// Provides DI extension methods to configure a GraphQL server.
+/// </summary>
+public static class HotChocolateAzFuncIsolatedProcessHostBuilderExtensions
+{
+    /// <summary>
+    /// Adds a GraphQL server and Azure Functions integration services for
+    /// Azure Functions Isolated processing model.
+    /// </summary>
+    /// <param name="hostBuilder">
+    /// The <see cref="IFunctionsHostBuilder"/>.
+    /// </param>
+    /// <param name="configure">
+    /// The GraphQL configuration function that will be invoked, for chained
+    /// configuration, when the Host is built.
+    /// </param>
+    /// <param name="maxAllowedRequestSize">
+    /// The max allowed GraphQL request size.
+    /// </param>
+    /// <param name="apiRoute">
+    /// The API route that was used in the GraphQL Azure Function.
+    /// </param>
+    /// <returns>
+    /// Returns the <see cref="IHostBuilder"/> so that host configuration can be chained.
+    /// </returns>
+    /// <exception cref="ArgumentNullException">
+    /// The <see cref="IServiceCollection"/> is <c>null</c>.
+    /// </exception>
+    public static IHostBuilder AddGraphQLFunction(
+        this IHostBuilder hostBuilder,
+        Action<IRequestExecutorBuilder> configure,
+        int maxAllowedRequestSize = GraphQLAzureFunctionsConstants.DefaultMaxRequests,
+        string apiRoute = GraphQLAzureFunctionsConstants.DefaultGraphQLRoute)
+    {
+        if (hostBuilder is null)
+        {
+            throw new ArgumentNullException(nameof(hostBuilder));
+        }
+
+        if (configure is null)
+        {
+            throw new ArgumentNullException(nameof(configure));
+        }
+
+        hostBuilder.ConfigureServices(services =>
+        {
+            var executorBuilder = services.AddGraphQLFunction(maxAllowedRequestSize, apiRoute);
+            configure(executorBuilder);
+        });
+
+        return hostBuilder;
+    }
+}

src/HotChocolate/AzureFunctions/src/HotChocolate.AzureFunctions.IsolatedProcess/Extensions/HttpRequestDataExtensions.cs

@@ -0,0 +1,34 @@
+using HotChocolate.AzureFunctions.IsolatedProcess.Extensions;
+using Microsoft.AspNetCore.Http;
+using Microsoft.Azure.Functions.Worker.Http;
+using Microsoft.Net.Http.Headers;
+
+namespace HotChocolate.AzureFunctions.IsolatedProcess;
+
+public static class HttpRequestDataExtensions
+{
+    public static string GetContentType(
+        this HttpRequestData httpRequestData,
+        string defaultValue = GraphQLAzureFunctionsConstants.DefaultJsonContentType)
+    {
+        var contentType = httpRequestData.Headers.TryGetValues(
+            HeaderNames.ContentType,
+            out var contentTypeHeaders)
+            ? contentTypeHeaders.FirstOrDefault()
+            : defaultValue;
+
+        return contentType ?? defaultValue;
+    }
+
+    public static HttpRequestData SetCurrentHttpContext(
+        this HttpRequestData httpRequestData,
+        HttpContext httpContext)
+    {
+        httpRequestData.FunctionContext.InstanceServices.SetCurrentHttpContext(httpContext);
+        return httpRequestData;
+    }
+
+    public static async Task<string?> ReadResponseContentAsync(
+        this HttpResponseData httpResponseData)
+        => await httpResponseData.Body.ReadStreamAsStringAsync().ConfigureAwait(false);
+}

src/HotChocolate/AzureFunctions/src/HotChocolate.AzureFunctions.IsolatedProcess/HotChocolate.AzureFunctions.IsolatedProcess.csproj

@@ -0,0 +1,21 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <PackageId>HotChocolate.AzureFunctions.IsolatedProcess</PackageId>
+    <AssemblyName>HotChocolate.AzureFunctions.IsolatedProcess</AssemblyName>
+    <RootNamespace>HotChocolate.AzureFunctions.IsolatedProcess</RootNamespace>
+    <Description>This package contains the GraphQL AzureFunctions Isolated Process integration for Hot Chocolate.</Description>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Abstractions" Version="1.1.0" />
+    <PackageReference Include="Microsoft.Azure.Functions.Worker.Core" Version="1.4.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\HotChocolate.AzureFunctions\HotChocolate.AzureFunctions.csproj" />
+  </ItemGroup>
+
+</Project>

src/HotChocolate/AzureFunctions/src/HotChocolate.AzureFunctions.IsolatedProcess/HttpContextShim.cs

@@ -0,0 +1,135 @@
+using System.Net;
+using HotChocolate.AzureFunctions.IsolatedProcess.Extensions;
+using Microsoft.AspNetCore.Http;
+using Microsoft.Azure.Functions.Worker.Http;
+using Microsoft.Extensions.Primitives;
+
+namespace HotChocolate.AzureFunctions.IsolatedProcess;
+
+public sealed class HttpContextShim : IDisposable
+{
+    private bool _disposed;
+
+    public HttpContextShim(HttpContext httpContext)
+    {
+        HttpContext = httpContext ??
+            throw new ArgumentNullException(nameof(httpContext));
+        IsolatedProcessHttpRequestData = null;
+    }
+
+    public HttpContextShim(HttpContext httpContext, HttpRequestData? httpRequestData)
+    {
+        HttpContext = httpContext ??
+            throw new ArgumentNullException(nameof(httpContext));
+        IsolatedProcessHttpRequestData = httpRequestData ??
+            throw new ArgumentNullException(nameof(httpRequestData));
+    }
+
+    private HttpRequestData? IsolatedProcessHttpRequestData { get; set; }
+
+    // Must keep the Reference so we can safely Dispose!
+    public HttpContext HttpContext { get; }
+
+    /// <summary>
+    /// Factory method to Create an HttpContext that is AspNetCore compatible.
+    /// All pertinent data from the HttpRequestData provided by the
+    /// Azure Functions Isolated Process will be marshaled
+    /// into the HttpContext for HotChocolate to consume.
+    /// NOTE: This is done as Factory method (and not in the Constructor)
+    /// to support optimized Async reading of incoming Request Content/Stream.
+    /// </summary>
+    public static Task<HttpContextShim> CreateHttpContextAsync(HttpRequestData httpRequestData)
+    {
+        if (httpRequestData == null)
+        {
+            throw new ArgumentNullException(nameof(httpRequestData));
+        }
+
+        // Factored out Async logic to Address SonarCloud concern for exceptions in Async flow...
+        return CreateHttpContextInternalAsync(httpRequestData);
+    }
+
+    private static async Task<HttpContextShim> CreateHttpContextInternalAsync(
+        HttpRequestData httpRequestData)
+    {
+        var requestBody = await httpRequestData.ReadAsStringAsync().ConfigureAwait(false);
+
+        var httpContext = new HttpContextBuilder().CreateHttpContext(
+            requestHttpMethod: httpRequestData.Method,
+            requestUri: httpRequestData.Url,
+            requestBody: requestBody,
+            requestBodyContentType: httpRequestData.GetContentType(),
+            requestHeaders: httpRequestData.Headers,
+            claimsIdentities: httpRequestData.Identities,
+            contextItems: httpRequestData.FunctionContext.Items
+        );
+
+        // Ensure we track the HttpContext internally for cleanup when disposed!
+        return new HttpContextShim(httpContext, httpRequestData);
+    }
+
+    /// <summary>
+    /// Create an HttpResponseData containing the proxied response content results;
+    /// marshaled back from the HttpContext.
+    /// </summary>
+    /// <returns></returns>
+    public async Task<HttpResponseData> CreateHttpResponseDataAsync()
+    {
+        var httpContext = HttpContext
+            ?? throw new NullReferenceException(
+                "The HttpContext has not been initialized correctly.");
+
+        var httpRequestData = IsolatedProcessHttpRequestData
+            ?? throw new NullReferenceException(
+                "The HttpRequestData has not been initialized correctly.");
+
+        var httpStatusCode = (HttpStatusCode)httpContext.Response.StatusCode;
+
+        // Initialize the Http Response...
+        var httpResponseData = httpRequestData.CreateResponse(httpStatusCode);
+
+        // Marshall over all Headers from the HttpContext...
+        // Note: This should also handle Cookies since Cookies are stored as a Header value ....
+        var responseHeaders = httpContext.Response.Headers;
+
+        if (responseHeaders.Count > 0)
+        {
+            foreach (var (key, value) in responseHeaders)
+            {
+                httpResponseData.Headers.TryAddWithoutValidation(
+                    key,
+                    value.Select(sv => sv?.ToString()));
+            }
+        }
+
+        // Marshall the original response Bytes from HotChocolate...
+        // Note: This enables full support for GraphQL Json results/errors,
+        // binary downloads, SDL, & BCP binary data.
+        var responseBytes = await httpContext.ReadResponseBytesAsync().ConfigureAwait(false);
+
+        if (responseBytes != null)
+        {
+            await httpResponseData.WriteBytesAsync(responseBytes).ConfigureAwait(false);
+        }
+
+        return httpResponseData;
+    }
+
+    public void Dispose()
+    {
+        Dispose(true);
+        GC.SuppressFinalize(this);
+    }
+
+    private void Dispose(bool disposing)
+    {
+        if (!_disposed)
+        {
+            if (disposing)
+            {
+                HttpContext.DisposeSafely();
+            }
+            _disposed = true;
+        }
+    }
+}

src/HotChocolate/AzureFunctions/src/HotChocolate.AzureFunctions/Extensions/HotChocolateAzureFunctionServiceCollectionExtensions.cs

@@ -33,23 +33,46 @@ public static class HotChocolateAzureFunctionServiceCollectionExtensions
     /// </exception>
     public static IRequestExecutorBuilder AddGraphQLFunction(
         this IServiceCollection services,
-        int maxAllowedRequestSize = 20 * 1000 * 1000,
-        string apiRoute = "/api/graphql")
+        int maxAllowedRequestSize = GraphQLAzureFunctionsConstants.DefaultMaxRequests,
+        string apiRoute = GraphQLAzureFunctionsConstants.DefaultGraphQLRoute)
     {
         if (services is null)
-        {
             throw new ArgumentNullException(nameof(services));
-        }
 
         var executorBuilder =
             services.AddGraphQLServer(maxAllowedRequestSize: maxAllowedRequestSize);
 
+        // Register AzFunc Custom Binding Extensions for In-Process Functions.
+        // NOTE: This does not work for Isolated Process due to (but is not harmful at all of
+        // isolated process; it just remains dormant):
+        // 1) Bindings always execute in-process and values must be marshaled between
+        // the Host Process & the Isolated Process Worker!
+        // 2) Currently only String values are supported (obviously due to above complexities).
+        // More Info. here (using Blob binding docs):
+        // https://docs.microsoft.com/en-us/azure/azure-functions/functions-bindings-storage-
+        // blob-input?tabs=isolated-process%2Cextensionv5&pivots=programming-language-csharp#usage
         services.TryAddEnumerable(
             ServiceDescriptor.Singleton<IExtensionConfigProvider, GraphQLExtensions>());
 
+        //Add the Request Executor Dependency...
+        services.AddAzureFunctionsGraphQLRequestExecutorDependency(apiRoute);
+
+        return executorBuilder;
+    }
+
+    /// <summary>
+    /// Internal method to adds the Request Executor dependency for Azure Functions both
+    /// in-process and isolate-process. Normal configuration should use AddGraphQLFunction()
+    /// extension instead which correctly call this internally.
+    /// </summary>
+    public static IServiceCollection AddAzureFunctionsGraphQLRequestExecutorDependency(
+        this IServiceCollection services,
+        string apiRoute = GraphQLAzureFunctionsConstants.DefaultGraphQLRoute
+    )
+    {
         services.AddSingleton<IGraphQLRequestExecutor>(sp =>
         {
-            PathString path = apiRoute.TrimEnd('/');
+            PathString path = apiRoute?.TrimEnd('/');
             var fileProvider = CreateFileProvider();
             var options = new GraphQLServerOptions();
 
@@ -74,7 +97,7 @@ public static IRequestExecutorBuilder AddGraphQLFunction(
             return new DefaultGraphQLRequestExecutor(pipeline, options);
         });
 
-        return executorBuilder;
+        return services;
     }
 
     /// <summary>