Make it easier to write to the result state and the result extensions. (

#5613)

src/HotChocolate/Core/src/Execution/Processing/DirectiveContext.cs

@@ -27,6 +27,8 @@ public DirectiveContext(IMiddlewareContext middlewareContext, IDirective directi
 
     public IOperation Operation => _middlewareContext.Operation;
 
+    public IOperationResultBuilder OperationResult => _middlewareContext.OperationResult;
+
     public ISelection Selection => _middlewareContext.Selection;
 
     public IVariableValueCollection Variables => _middlewareContext.Variables;

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

@@ -4,6 +4,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using HotChocolate.Execution.Properties;
+using HotChocolate.Execution.Serialization;
 using HotChocolate.Resolvers;
 using HotChocolate.Types;
 using Microsoft.Extensions.DependencyInjection;
@@ -12,6 +13,7 @@ namespace HotChocolate.Execution.Processing;
 
 internal partial class MiddlewareContext : IMiddlewareContext
 {
+    private readonly OperationResultBuilderFacade _operationResultBuilder = new();
     private readonly List<Func<ValueTask>> _cleanupTasks = new();
     private OperationContext _operationContext = default!;
     private IServiceProvider _services = default!;
@@ -29,6 +31,8 @@ public IServiceProvider Services
 
     public IOperation Operation => _operationContext.Operation;
 
+    public IOperationResultBuilder OperationResult => _operationResultBuilder;
+
     public IDictionary<string, object?> ContextData => _operationContext.ContextData;
 
     public IVariableValueCollection Variables => _operationContext.Variables;
@@ -69,6 +73,7 @@ public IReadOnlyList<ISelection> GetSelections(
             for (var i = 0; i < selectionCount; i++)
             {
                 var childSelection = Unsafe.Add(ref selectionRef, i);
+
                 if (childSelection.IsIncluded(operationIncludeFlags, allowInternals))
                 {
                     finalFields.Add(childSelection);
@@ -90,11 +95,12 @@ public void ReportError(string errorMessage)
                 nameof(errorMessage));
         }
 
-        ReportError(ErrorBuilder.New()
-            .SetMessage(errorMessage)
-            .SetPath(Path)
-            .AddLocation(_selection.SyntaxNode)
-            .Build());
+        ReportError(
+            ErrorBuilder.New()
+                .SetMessage(errorMessage)
+                .SetPath(Path)
+                .AddLocation(_selection.SyntaxNode)
+                .Build());
     }
 
     public void ReportError(Exception exception, Action<IErrorBuilder>? configure = null)
@@ -182,7 +188,9 @@ public async ValueTask<T> ResolveAsync<T>()
             _hasResolverResult = true;
         }
 
-        return _resolverResult is null ? default! : (T)_resolverResult;
+        return _resolverResult is null
+            ? default!
+            : (T)_resolverResult;
     }
 
     public T Resolver<T>() =>
@@ -257,4 +265,15 @@ public IMiddlewareContext Clone()
 
     IResolverContext IResolverContext.Clone()
         => Clone();
+
+    private sealed class OperationResultBuilderFacade : IOperationResultBuilder
+    {
+        public OperationContext Context { get; set; } = default!;
+
+        public void SetResultState(string key, object? value)
+            => Context.Result.SetContextData(key, value);
+
+        public void SetExtension<TValue>(string key, TValue value)
+            => Context.Result.SetExtension(key, new NeedsFormatting<TValue>(value));
+    }
 }

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

@@ -24,6 +24,7 @@ public void Initialize(
         IImmutableDictionary<string, object?> scopedContextData)
     {
         _operationContext = operationContext;
+        _operationResultBuilder.Context = _operationContext;
         _services = operationContext.Services;
         _selection = selection;
         ParentResult = parentResult;
@@ -49,6 +50,7 @@ public void Clean()
         _hasResolverResult = false;
         _result = default;
         _parser = default!;
+        _operationResultBuilder.Context = default!;
 
         Path = default!;
         ScopedContextData = default!;

src/HotChocolate/Core/src/Execution/Serialization/JsonResultFormatter.cs

@@ -4,14 +4,14 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
 using System.Text;
 using System.Text.Encodings.Web;
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
 using HotChocolate.Execution.Processing;
 using HotChocolate.Utilities;
+using static System.Text.Json.JsonSerializerDefaults;
 using static HotChocolate.Execution.ThrowHelper;
 
 namespace HotChocolate.Execution.Serialization;
@@ -22,6 +22,7 @@ namespace HotChocolate.Execution.Serialization;
 public sealed partial class JsonResultFormatter : IQueryResultFormatter, IExecutionResultFormatter
 {
     private readonly JsonWriterOptions _options;
+    private readonly JsonSerializerOptions _serializerOptions;
 
     /// <summary>
     /// Initializes a new instance of <see cref="JsonResultFormatter"/>.
@@ -34,7 +35,8 @@ public sealed partial class JsonResultFormatter : IQueryResultFormatter, IExecut
     /// </param>
     public JsonResultFormatter(bool indented = false, JavaScriptEncoder? encoder = null)
     {
-        _options = new JsonWriterOptions { Indented = indented, Encoder = encoder };
+        _options = new() { Indented = indented, Encoder = encoder };
+        _serializerOptions = new(Web) { WriteIndented = indented, Encoder = encoder };
     }
 
     /// <inheritdoc cref="IExecutionResultFormatter.FormatAsync"/>
@@ -606,7 +608,7 @@ private void WriteFieldValue(
                 WriteListResult(writer, resultMapList);
                 break;
 
-#if NET5_0_OR_GREATER
+#if NET6_0_OR_GREATER
             case JsonElement element:
                 WriteJsonElement(writer, element);
                 break;
@@ -615,6 +617,10 @@ private void WriteFieldValue(
                 writer.WriteRawValue(rawJsonValue.Value.Span, true);
                 break;
 #endif
+            case NeedsFormatting unformatted:
+                unformatted.FormatValue(writer, _serializerOptions);
+                break;
+
             case Dictionary<string, object?> dict:
                 WriteDictionary(writer, dict);
                 break;

src/HotChocolate/Core/src/Execution/Serialization/NeedsFormatting.cs

@@ -0,0 +1,61 @@
+using System.Text.Json;
+
+namespace HotChocolate.Execution.Serialization;
+
+/// <summary>
+/// This helper class allows us to indicate to the formatters that the inner value
+/// has a custom formatter.
+/// </summary>
+/// <remarks>
+/// The downside of this helper is that we bind it explicitly to JSON.
+/// If there were alternative query formatter that use different formats we would get
+/// into trouble with this.
+///
+/// This is also the reason for keeping this internal.
+/// </remarks>
+internal abstract class NeedsFormatting
+{
+    /// <summary>
+    /// Formats the value as JSON
+    /// </summary>
+    /// <param name="writer">
+    /// The JSON writer.
+    /// </param>
+    /// <param name="options">
+    /// The JSON serializer options.
+    /// </param>
+    public abstract void FormatValue(Utf8JsonWriter writer, JsonSerializerOptions options);
+}
+
+/// <summary>
+/// This helper class allows us to indicate to the formatters that the inner value
+/// has a custom formatter.
+/// </summary>
+/// <remarks>
+/// The downside of this helper is that we bind it explicitly to JSON.
+/// If there were alternative query formatter that use different formats we would get
+/// into trouble with this.
+///
+/// This is also the reason for keeping this internal.
+/// </remarks>
+internal sealed class NeedsFormatting<TValue> : NeedsFormatting
+{
+    private readonly TValue _value;
+
+    public NeedsFormatting(TValue value)
+    {
+        _value = value;
+    }
+
+    /// <summary>
+    /// Formats the value as JSON
+    /// </summary>
+    /// <param name="writer">
+    /// The JSON writer.
+    /// </param>
+    /// <param name="options">
+    /// The JSON serializer options.
+    /// </param>
+    public override void FormatValue(Utf8JsonWriter writer, JsonSerializerOptions options)
+        => JsonSerializer.Serialize(writer, _value, options);
+}

src/HotChocolate/Core/src/Execution/Serialization/RawJsonValue.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Text.Json;
 
 namespace HotChocolate.Execution.Serialization;
 
@@ -7,6 +8,13 @@ namespace HotChocolate.Execution.Serialization;
 /// The JSON query result formatter will take the inner <see cref="Value"/>
 /// and writes it without validation to the JSON response object.
 /// </summary>
+/// <remarks>
+/// The downside of this helper is that we bind it explicitly to JSON.
+/// If there were alternative query formatter that use different formats we would get
+/// into trouble with this.
+///
+/// This is also the reason for keeping this internal.
+/// </remarks>
 internal readonly struct RawJsonValue
 {
     /// <summary>

src/HotChocolate/Core/src/Types/Resolvers/IMiddlewareContext.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
-using HotChocolate.Execution;
 using HotChocolate.Types;
 
 #nullable enable
@@ -30,6 +29,11 @@ public interface IMiddlewareContext : IResolverContext
     /// <value></value>
     bool IsResultModified { get; }
 
+    /// <summary>
+    /// Allows to modify some aspects of the overall operation result.
+    /// </summary>
+    IOperationResultBuilder OperationResult { get; }
+
     /// <summary>
     /// Executes the field resolver and returns its result.
     /// </summary>

src/HotChocolate/Core/src/Types/Resolvers/IOperationResultBuilder.cs

@@ -0,0 +1,34 @@
+#nullable enable
+namespace HotChocolate.Resolvers;
+
+/// <summary>
+/// This helper allows modifying some aspects of the overall operation result object.
+/// </summary>
+public interface IOperationResultBuilder
+{
+    /// <summary>
+    /// Sets a property on the result context data which can be used for further processing
+    /// in the request pipeline.
+    /// </summary>
+    /// <param name="key">The key.</param>
+    /// <param name="value">The value.</param>
+    void SetResultState(string key, object? value);
+
+    /// <summary>
+    /// Sets a property on the result extension data which will
+    /// be serialized and send to the consumer.
+    ///
+    /// <code>
+    /// {
+    ///    ...
+    ///    "extensions": {
+    ///       "yourKey": "yourValue"
+    ///    }
+    /// }
+    /// </code>
+    ///
+    /// </summary>
+    /// <param name="key">The key.</param>
+    /// <param name="value">The value.</param>
+    void SetExtension<TValue>(string key, TValue value);
+}