Simplify DI Support (#6994)

Author: michaelstaib

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "8.0.202",
+    "version": "8.0.101",
     "rollForward": "latestMajor"
   }
 }

src/HotChocolate/ApolloFederation/test/ApolloFederation.Tests/CertificationSchema/AnnotationBased/SchemaSetup.cs

@@ -13,6 +13,5 @@ public static async Task<IRequestExecutor> CreateAsync()
             .AddGraphQL()
             .AddApolloFederation()
             .AddQueryType<Query>()
-            .RegisterService<Data>()
             .BuildRequestExecutorAsync();
 }

src/HotChocolate/ApolloFederation/test/ApolloFederation.Tests/CertificationSchema/CodeFirst/SchemaSetup.cs

@@ -13,6 +13,5 @@ public static async Task<IRequestExecutor> CreateAsync()
             .AddGraphQL()
             .AddApolloFederation()
             .AddQueryType<QueryType>()
-            .RegisterService<Data>()
             .BuildRequestExecutorAsync();
 }

src/HotChocolate/Core/src/Abstractions/ScopedServiceAttribute.cs

@@ -11,12 +11,8 @@ public class ServiceAttribute : Attribute
     /// <summary>
     /// Marks a resolver parameter as a service that shall be injected by the execution engine.
     /// </summary>
-    /// <param name="kind">
-    /// The scope of the service.
-    /// </param>
-    public ServiceAttribute(ServiceKind kind = ServiceKind.Default)
+    public ServiceAttribute()
     {
-        Kind = kind;
     }
 
 #if NET8_0_OR_GREATER
@@ -26,24 +22,14 @@ public ServiceAttribute(ServiceKind kind = ServiceKind.Default)
     /// <param name="key">
     /// A key that shall be used to resolve the service.
     /// </param>
-    /// <param name="kind">
-    /// The scope of the service.
-    /// </param>
-    public ServiceAttribute(string key, ServiceKind kind = ServiceKind.Default)
+    public ServiceAttribute(string key)
     {
         Key = key;
-        Kind = kind;
     }
 
     /// <summary>
     /// Gets the key that shall be used to resolve the service.
     /// </summary>
     public string? Key { get; }
 #endif
-
-    /// <summary>
-    /// Gets the service kind which specifies the way the service
-    /// shall be injected and handled by the execution engine.
-    /// </summary>
-    public ServiceKind Kind { get; }
 }

src/HotChocolate/Core/src/Abstractions/ServiceAttribute.cs

@@ -2,6 +2,7 @@
 using HotChocolate.Execution.DependencyInjection;
 using HotChocolate.Execution.Processing;
 using HotChocolate.Execution.Processing.Tasks;
+using HotChocolate.Resolvers;
 using HotChocolate.Utilities;
 
 namespace Microsoft.Extensions.DependencyInjection;
@@ -17,28 +18,17 @@ namespace Microsoft.Extensions.DependencyInjection;
 ///
 /// The <see cref="OperationContextFactory"/> MUST be a singleton.
 /// </summary>
-internal sealed class OperationContextFactory : IFactory<OperationContext>
+internal sealed class OperationContextFactory(
+    IFactory<ResolverTask> resolverTaskFactory,
+    ResultPool resultPool,
+    ITypeConverter typeConverter,
+    AggregateServiceScopeInitializer serviceScopeInitializer)
+    : IFactory<OperationContext>
 {
-    private readonly IFactory<ResolverTask> _resolverTaskFactory;
-    private readonly ResultPool _resultPool;
-    private readonly ITypeConverter _typeConverter;
-
-    public OperationContextFactory(
-        IFactory<ResolverTask> resolverTaskFactory,
-        ResultPool resultPool,
-        ITypeConverter typeConverter)
-    {
-        _resolverTaskFactory = resolverTaskFactory ??
-            throw new ArgumentNullException(nameof(resolverTaskFactory));
-        _resultPool = resultPool ??
-            throw new ArgumentNullException(nameof(resultPool));
-        _typeConverter = typeConverter ??
-            throw new ArgumentNullException(nameof(typeConverter));
-    }
-
     public OperationContext Create()
         => new OperationContext(
-            _resolverTaskFactory,
-            new ResultBuilder(_resultPool),
-            _typeConverter);
+            resolverTaskFactory,
+            new ResultBuilder(resultPool),
+            typeConverter,
+            serviceScopeInitializer);
 }

src/HotChocolate/Core/src/Abstractions/ServiceKind.cs

@@ -0,0 +1,55 @@
+using System;
+using HotChocolate.Execution.Configuration;
+using HotChocolate.Resolvers;
+
+// ReSharper disable once CheckNamespace
+namespace Microsoft.Extensions.DependencyInjection;
+
+public static partial class RequestExecutorBuilderExtensions
+{
+    /// <summary>
+    /// Adds a initializer to copy state between a request scoped service instance and
+    /// a resolver scoped service instance.
+    /// </summary>
+    /// <param name="builder">
+    /// The request executor builder.
+    /// </param>
+    /// <param name="initializer">
+    /// The initializer that is used to initialize the service scope.
+    /// </param>
+    /// <typeparam name="TService">
+    /// The type of the service that shall be initialized.
+    /// </typeparam>
+    /// <returns></returns>
+    /// <exception cref="ArgumentNullException">
+    /// The <paramref name="builder"/> is <c>null</c>.
+    /// </exception>
+    public static IRequestExecutorBuilder AddScopedServiceInitializer<TService>(
+        this IRequestExecutorBuilder builder,
+        Action<TService, TService> initializer)
+    {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        if (initializer == null)
+        {
+            throw new ArgumentNullException(nameof(initializer));
+        }
+
+        builder.Services.AddSingleton<IServiceScopeInitializer>(new DelegateServiceInitializer<TService>(initializer));
+        return builder;
+    }
+}
+
+file sealed class DelegateServiceInitializer<TService>(
+    Action<TService, TService> initializer)
+    : ServiceInitializer<TService>
+{
+    private readonly Action<TService, TService> _initializer = initializer ?? 
+        throw new ArgumentNullException(nameof(initializer));
+
+    protected override void Initialize(TService requestScopeService, TService resolverScopeService)
+        => _initializer(requestScopeService, resolverScopeService);
+}

src/HotChocolate/Core/src/Execution/DependencyInjection/Factories/OperationContextFactory.cs

@@ -10,6 +10,7 @@
 using HotChocolate.Execution.Processing;
 using HotChocolate.Fetching;
 using HotChocolate.Language;
+using HotChocolate.Resolvers;
 using Microsoft.Extensions.DependencyInjection.Extensions;
 using Microsoft.Extensions.ObjectPool;
 
@@ -36,6 +37,7 @@ public static IServiceCollection AddGraphQLCore(this IServiceCollection services
         services.TryAddSingleton<ObjectPoolProvider, DefaultObjectPoolProvider>();
         services.TryAddSingleton<DefaultRequestContextAccessor>();
         services.TryAddSingleton<IRequestContextAccessor>(sp => sp.GetRequiredService<DefaultRequestContextAccessor>());
+        services.TryAddSingleton<AggregateServiceScopeInitializer>();
 
         services.TryAddSingleton<ObjectPool<StringBuilder>>(sp =>
         {