Track JSON perf with source generation

Author: pranavkm

src/Components/benchmarkapps/Wasm.Performance/TestApp/Pages/Json.razor

@@ -8,6 +8,7 @@
 
 <button id="serialize-small" @onclick=SerializeSmall>Serialize (small)</button>
 <button id="serialize-large" @onclick=SerializeLarge>Serialize (large)</button>
+<button id="serialize-large-sourcegen" @onclick=SerializeLargeSourceGen>Serialize (large with sourcegen)</button>
 
 <p><pre style="border: 1px solid black; overflow: scroll;">@serializedValue</pre></p>
 @if (serializedValue != null)
@@ -17,6 +18,7 @@
 
 <button id="deserialize-small" @onclick=DeserializeSmall>Deserialize (small)</button>
 <button id="deserialize-large" @onclick=DeserializeLarge>Deserialize (large)</button>
+<button id="deserialize-large-sourcegen" @onclick=DeserializeLargeSourceGen>Deserialize (large with sourcegen)</button>
 
 @if (numPeopleDeserialized > 0)
 {
@@ -26,6 +28,7 @@
 @code {
     Person smallOrgChart = Person.GenerateOrgChart(1, 4);
     Person largeOrgChart = Person.GenerateOrgChart(5, 4);
+    PersonJsonContext personJsonContext = new(new(JsonSerializerDefaults.Web));
     string smallOrgChartJson;
     string largeOrgChartJson;
     int numPeopleDeserialized;
@@ -55,12 +58,18 @@
     void SerializeLarge()
         => serializedValue = JsonSerializer.Serialize(largeOrgChart);
 
+    void SerializeLargeSourceGen()
+        => serializedValue = JsonSerializer.Serialize(largeOrgChart, personJsonContext.Person);
+
     void DeserializeSmall()
         => numPeopleDeserialized = Deserialize(smallOrgChartJson);
 
     void DeserializeLarge()
         => numPeopleDeserialized = Deserialize(largeOrgChartJson);
 
+    void DeserializeLargeSourceGen()
+        => numPeopleDeserialized = CountPeople(JsonSerializer.Deserialize<Person>(largeOrgChartJson, personJsonContext.Person));
+
     static int Deserialize(string json)
     {
         var ceo = JsonSerializer.Deserialize<Person>(json);

src/Components/benchmarkapps/Wasm.Performance/TestApp/Person.cs

@@ -15,7 +15,7 @@ public class Person
         public int Salary { get; set; }
         public bool IsAdmin { get; set; }
         public List<Person> Subordinates { get; set; }
-        public Dictionary<string, object> SecurityClearances { get; set; }
+        public Dictionary<string, bool> SecurityClearances { get; set; }
 
         public static Person GenerateOrgChart(int totalDepth, int numDescendantsPerNode, int thisDepth = 0, string namePrefix = null, int siblingIndex = 0)
         {
@@ -28,7 +28,7 @@ public static Person GenerateOrgChart(int totalDepth, int numDescendantsPerNode,
                 IsAdmin = siblingIndex % 2 == 0,
                 Salary = 10000000 / (thisDepth + 1),
                 SecurityClearances = Clearances
-                    .ToDictionary(c => c, _ => (object)(rng.Next(0, 2) == 0)),
+                    .ToDictionary(c => c, _ => rng.Next(0, 2) == 0),
                 Subordinates = Enumerable.Range(0, thisDepth < totalDepth ? numDescendantsPerNode : 0)
                     .Select(index => GenerateOrgChart(totalDepth, numDescendantsPerNode, thisDepth + 1, name, index))
                     .ToList()

src/Components/benchmarkapps/Wasm.Performance/TestApp/PersonJsonContext.cs

@@ -0,0 +1,12 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Text.Json.Serialization;
+
+namespace Wasm.Performance.TestApp
+{
+    [JsonSerializable(typeof(Person), GenerationMode = JsonSourceGenerationMode.MetadataAndSerialization)]
+    internal partial class PersonJsonContext : JsonSerializerContext
+    {
+    }
+}

src/Components/benchmarkapps/Wasm.Performance/TestApp/Wasm.Performance.TestApp.csproj

@@ -13,5 +13,6 @@
 
   <ItemGroup>
     <Reference Include="Microsoft.AspNetCore.Components.WebAssembly" />
+    <Reference Include="System.Text.Json" />
   </ItemGroup>
 </Project>

src/Components/benchmarkapps/Wasm.Performance/TestApp/wwwroot/benchmarks/jsonHandling.js

@@ -31,6 +31,14 @@ group('JSON handling', () => {
       }
     });
 
+  benchmark('Serialize 340kb (Source Generated)', () =>
+    benchmarkJson(app, '#serialize-large-sourcegen', '#serialized-length', 339803), {
+      descriptor: {
+        name: 'blazorwasm/jsonserialize-sourcegen-340kb',
+        description: 'Serialize JSON (SourceGen) 340kb - Time in ms'
+      }
+    });
+
   benchmark('Deserialize 1kb', () =>
     benchmarkJson(app, '#deserialize-small', '#deserialized-count', 5), {
       descriptor: {
@@ -47,6 +55,14 @@ group('JSON handling', () => {
       }
     });
 
+  benchmark('Deserialize 340kb (Source Generated)', () =>
+    benchmarkJson(app, '#deserialize-large-sourcegen', '#deserialized-count', 1365), {
+      descriptor: {
+        name: 'blazorwasm/jsondeserialize-sourcegen-340kb',
+        description: 'Deserialize JSON (SourceGen) 340kb - Time in ms'
+      }
+    });
+
   benchmark('Serialize 340kb (JavaScript)', () => {
     const json = JSON.stringify(largeObjectToSerialize);
     if (json.length !== 339803) {