Optimized Resolver Context Initialization

src/HotChocolate/Core/src/Execution/Processing/MiddlewareContext.Pooling.cs

@@ -6,6 +6,9 @@ namespace HotChocolate.Execution.Processing;
 
 internal partial class MiddlewareContext
 {
+    private static readonly ImmutableDictionary<string, object?> _emptyLocalContextData =
+        ImmutableDictionary<string, object?>.Empty;
+
     public MiddlewareContext()
     {
         _childContext = new PureResolverContext(this);
@@ -26,10 +29,10 @@ public MiddlewareContext()
         ParentResult = parentResult;
         ResponseIndex = responseIndex;
         _parent = parent;
-        _parser = _operationContext.Services.GetRequiredService<InputParser>();
+        _parser = operationContext.InputParser;
         Path = path;
         ScopedContextData = scopedContextData;
-        LocalContextData = ImmutableDictionary<string, object?>.Empty;
+        LocalContextData = _emptyLocalContextData;
         Arguments = _selection.Arguments;
         RequestAborted = _operationContext.RequestAborted;
     }

src/HotChocolate/Core/src/Execution/Processing/OperationContext.Pooling.cs

@@ -6,7 +6,9 @@
 using HotChocolate.Execution.Instrumentation;
 using HotChocolate.Execution.Processing.Tasks;
 using HotChocolate.Fetching;
+using HotChocolate.Types;
 using HotChocolate.Utilities;
+using Microsoft.Extensions.DependencyInjection;
 using static HotChocolate.Execution.ThrowHelper;
 
 namespace HotChocolate.Execution.Processing;
@@ -29,6 +31,7 @@ internal sealed partial class OperationContext
     private IServiceProvider _services = default!;
     private Func<object?> _resolveQueryRootValue = default!;
     private IBatchDispatcher _batchDispatcher = default!;
+    private InputParser _inputParser = default!;
     private object? _rootValue;
     private bool _isInitialized;
 
@@ -66,6 +69,7 @@ internal sealed partial class OperationContext
         _operation = operation;
         _variables = variables;
         _services = scopedServices;
+        _inputParser = scopedServices.GetRequiredService<InputParser>();
         _rootValue = rootValue;
         _resolveQueryRootValue = resolveQueryRootValue;
         _batchDispatcher = batchDispatcher;
@@ -88,6 +92,7 @@ public void InitializeFrom(OperationContext context)
         _operation = context._operation;
         _variables = context._variables;
         _services = context._services;
+        _inputParser = context._inputParser;
         _rootValue = context._rootValue;
         _resolveQueryRootValue = context._resolveQueryRootValue;
         _batchDispatcher = context._batchDispatcher;

src/HotChocolate/Core/src/Execution/Processing/OperationContext.Services.cs

@@ -1,30 +1,25 @@
 using System;
+using HotChocolate.Types;
 
 namespace HotChocolate.Execution.Processing;
 
+// note: we are not asserting the properties here for performance reasons.
+// These properties are used by the middleware context which means that potentially
+// all fields will access them.
 internal sealed partial class OperationContext
 {
     /// <summary>
     /// Gets the request scoped services
     /// </summary>
-    public IServiceProvider Services
-    {
-        get
-        {
-            AssertInitialized();
-            return _services;
-        }
-    }
+    public IServiceProvider Services => _services;
 
     /// <summary>
     /// Gets the activator helper class.
     /// </summary>
-    public IActivator Activator
-    {
-        get
-        {
-            AssertInitialized();
-            return _activator;
-        }
-    }
+    public IActivator Activator => _activator;
+
+    /// <summary>
+    /// Gets access to the input parser.
+    /// </summary>
+    public InputParser InputParser => _inputParser;
 }