Use the built-in JSON stream configuration provider

CHANGELOG.md

@@ -8,7 +8,8 @@ All notable changes to this project will be documented in this file.
 - Removed the Newtonsoft.Json companion package and custom serializer abstraction.
 - Made `AddObject` generic and added `JsonTypeInfo<T>` overloads for source-generated System.Text.Json metadata.
 - Added `AddObjectAsFallback` for registering object configuration at the lowest precedence.
-- Aligned object flattening with .NET 10 configuration semantics for null values, empty strings, empty objects, empty arrays, and null array elements.
+- Aligned object configuration with .NET 10 JSON configuration semantics for null values, empty strings, empty objects, empty arrays, and null array elements.
+- Reused the built-in JSON stream configuration provider instead of maintaining a custom JSON-to-configuration flattener and provider.
 
 ## 3.0.1 - 2024-07-12
 

Directory.Packages.props

@@ -13,6 +13,7 @@
     <PackageVersion Include="GitHubActionsTestLogger" Version="3.0.5" />
     <PackageVersion Include="Microsoft.Extensions.Configuration" Version="10.0.11" />
     <PackageVersion Include="Microsoft.Extensions.Configuration.Binder" Version="10.0.11" />
+    <PackageVersion Include="Microsoft.Extensions.Configuration.Json" Version="10.0.11" />
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
     <PackageVersion Include="MinVer" Version="7.0.0" />
     <PackageVersion Include="Moq" Version="4.18.4" />

src/Objects/Internal/SystemTextJsonConfigurationSerializer.cs

@@ -1,19 +1,56 @@
+using System;
+using System.IO;
 using System.Text.Json;
 using System.Text.Json.Serialization.Metadata;
+using Microsoft.Extensions.Configuration;
 
 namespace Kralizek.Extensions.Configuration.Internal;
 
 internal static class SystemTextJsonConfigurationSerializer
 {
     private static readonly JsonSerializerOptions JsonOptions = new();
 
-    public static JsonElement Serialize<T>(T source)
+    public static MemoryStream Serialize<T>(T source, string rootSectionName)
     {
-        return JsonSerializer.SerializeToElement(source, JsonOptions);
+        return Serialize(rootSectionName, writer => JsonSerializer.Serialize(writer, source, JsonOptions));
     }
 
-    public static JsonElement Serialize<T>(T source, JsonTypeInfo<T> jsonTypeInfo)
+    public static MemoryStream Serialize<T>(T source, JsonTypeInfo<T> jsonTypeInfo, string rootSectionName)
     {
-        return JsonSerializer.SerializeToElement(source, jsonTypeInfo);
+        return Serialize(rootSectionName, writer => JsonSerializer.Serialize(writer, source, jsonTypeInfo));
+    }
+
+    private static MemoryStream Serialize(string rootSectionName, Action<Utf8JsonWriter> serialize)
+    {
+        var stream = new MemoryStream();
+
+        using (var writer = new Utf8JsonWriter(stream))
+        {
+            var rootSections = GetRootSections(rootSectionName);
+
+            foreach (var rootSection in rootSections)
+            {
+                writer.WriteStartObject();
+                writer.WritePropertyName(rootSection);
+            }
+
+            serialize(writer);
+
+            for (var index = 0; index < rootSections.Length; index++)
+            {
+                writer.WriteEndObject();
+            }
+        }
+
+        stream.Position = 0;
+
+        return stream;
+    }
+
+    private static string[] GetRootSections(string rootSectionName)
+    {
+        return string.IsNullOrEmpty(rootSectionName)
+            ? Array.Empty<string>()
+            : rootSectionName.Split(new[] { ConfigurationPath.KeyDelimiter }, StringSplitOptions.None);
     }
 }

src/Objects/ObjectConfigurationExtensions.cs

@@ -1,8 +1,8 @@
 using System;
-using System.Collections.Generic;
-using System.Text.Json;
+using System.IO;
 using System.Text.Json.Serialization.Metadata;
 using Kralizek.Extensions.Configuration.Internal;
+using Microsoft.Extensions.Configuration.Json;
 
 // ReSharper disable CheckNamespace
 
@@ -12,7 +12,7 @@ public static class ObjectConfigurationExtensions
 {
     public static IConfigurationBuilder AddObject<T>(this IConfigurationBuilder configurationBuilder, T? objectToAdd, string? rootSectionName = "")
     {
-        return AddObject(configurationBuilder, objectToAdd, rootSectionName, static value => SystemTextJsonConfigurationSerializer.Serialize(value));
+        return AddObject(configurationBuilder, objectToAdd, rootSectionName, static (value, rootSection) => SystemTextJsonConfigurationSerializer.Serialize(value, rootSection));
     }
 
     public static IConfigurationBuilder AddObject<T>(this IConfigurationBuilder configurationBuilder, T? objectToAdd, JsonTypeInfo<T> jsonTypeInfo, string? rootSectionName = "")
@@ -22,12 +22,12 @@ public static IConfigurationBuilder AddObject<T>(this IConfigurationBuilder conf
             throw new ArgumentNullException(nameof(jsonTypeInfo));
         }
 
-        return AddObject(configurationBuilder, objectToAdd, rootSectionName, value => SystemTextJsonConfigurationSerializer.Serialize(value, jsonTypeInfo));
+        return AddObject(configurationBuilder, objectToAdd, rootSectionName, (value, rootSection) => SystemTextJsonConfigurationSerializer.Serialize(value, jsonTypeInfo, rootSection));
     }
 
     public static IConfigurationBuilder AddObjectAsFallback<T>(this IConfigurationBuilder configurationBuilder, T? objectToAdd, string? rootSectionName = "")
     {
-        return AddObjectAsFallback(configurationBuilder, objectToAdd, rootSectionName, static value => SystemTextJsonConfigurationSerializer.Serialize(value));
+        return AddObjectAsFallback(configurationBuilder, objectToAdd, rootSectionName, static (value, rootSection) => SystemTextJsonConfigurationSerializer.Serialize(value, rootSection));
     }
 
     public static IConfigurationBuilder AddObjectAsFallback<T>(this IConfigurationBuilder configurationBuilder, T? objectToAdd, JsonTypeInfo<T> jsonTypeInfo, string? rootSectionName = "")
@@ -37,10 +37,10 @@ public static IConfigurationBuilder AddObjectAsFallback<T>(this IConfigurationBu
             throw new ArgumentNullException(nameof(jsonTypeInfo));
         }
 
-        return AddObjectAsFallback(configurationBuilder, objectToAdd, rootSectionName, value => SystemTextJsonConfigurationSerializer.Serialize(value, jsonTypeInfo));
+        return AddObjectAsFallback(configurationBuilder, objectToAdd, rootSectionName, (value, rootSection) => SystemTextJsonConfigurationSerializer.Serialize(value, jsonTypeInfo, rootSection));
     }
 
-    private static IConfigurationBuilder AddObject<T>(IConfigurationBuilder configurationBuilder, T? objectToAdd, string? rootSectionName, Func<T, JsonElement> serialize)
+    private static IConfigurationBuilder AddObject<T>(IConfigurationBuilder configurationBuilder, T? objectToAdd, string? rootSectionName, Func<T, string, Stream> serialize)
     {
         if (configurationBuilder is null)
         {
@@ -52,12 +52,12 @@ private static IConfigurationBuilder AddObject<T>(IConfigurationBuilder configur
             return configurationBuilder;
         }
 
-        configurationBuilder.Add(CreateSource(objectToAdd, rootSectionName, serialize));
+        configurationBuilder.Sources.Add(CreateSource(objectToAdd, rootSectionName, serialize));
 
         return configurationBuilder;
     }
 
-    private static IConfigurationBuilder AddObjectAsFallback<T>(IConfigurationBuilder configurationBuilder, T? objectToAdd, string? rootSectionName, Func<T, JsonElement> serialize)
+    private static IConfigurationBuilder AddObjectAsFallback<T>(IConfigurationBuilder configurationBuilder, T? objectToAdd, string? rootSectionName, Func<T, string, Stream> serialize)
     {
         if (configurationBuilder is null)
         {
@@ -74,15 +74,11 @@ private static IConfigurationBuilder AddObjectAsFallback<T>(IConfigurationBuilde
         return configurationBuilder;
     }
 
-    private static ObjectConfigurationSource CreateSource<T>(T objectToAdd, string? rootSectionName, Func<T, JsonElement> serialize)
+    private static JsonStreamConfigurationSource CreateSource<T>(T objectToAdd, string? rootSectionName, Func<T, string, Stream> serialize)
     {
-        var rootSection = rootSectionName ?? string.Empty;
-
-        return new ObjectConfigurationSource(() =>
+        return new JsonStreamConfigurationSource
         {
-            var json = serialize(objectToAdd);
-
-            return JsonConfigurationFlattener.Flatten(json, rootSection);
-        });
+            Stream = serialize(objectToAdd, rootSectionName ?? string.Empty)
+        };
     }
 }

src/Objects/Objects.csproj

@@ -17,6 +17,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Configuration" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" />
     <PackageReference Include="PolySharp" PrivateAssets="all" />
     <PackageReference Include="System.Text.Json" />
   </ItemGroup>