perf: Use YamlDeserializer as singleton instance

src/Docfx.Build/ApiPage/ApiPageProcessor.cs

@@ -11,6 +11,8 @@ namespace Docfx.Build.ApiPage;
 
 class ApiPageDocumentProcessor(IMarkdownService markdownService) : IDocumentProcessor
 {
+    private static IDeserializer deserializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization().Build();
+
     IEnumerable<IDocumentBuildStep> IDocumentProcessor.BuildSteps => Array.Empty<IDocumentBuildStep>();
     void IDocumentProcessor.UpdateHref(FileModel model, IDocumentBuildContext context) { }
 
@@ -35,7 +37,6 @@ public ProcessingPriority GetProcessingPriority(FileAndType file)
 
     public FileModel Load(FileAndType file, ImmutableDictionary<string, object> metadata)
     {
-        var deserializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization().Build();
         var yml = EnvironmentContext.FileAbstractLayer.ReadAllText(file.File);
         var json = JsonSerializer.Serialize(deserializer.Deserialize<object>(yml));
         var data = JsonSerializer.Deserialize<ApiPage>(json, ApiPage.JsonSerializerOptions);

src/Docfx.Common/YamlUtility.cs

@@ -12,8 +12,8 @@ namespace Docfx.Common;
 
 public static class YamlUtility
 {
-    private static readonly ThreadLocal<YamlSerializer> serializer = new(() => new YamlSerializer(SerializationOptions.DisableAliases));
-    private static readonly ThreadLocal<YamlDeserializer> deserializer = new(() => new YamlDeserializer(ignoreUnmatched: true));
+    private static readonly YamlSerializer serializer = new(SerializationOptions.DisableAliases);
+    private static readonly YamlDeserializer deserializer = new(ignoreUnmatched: true);
 
     public static void Serialize(TextWriter writer, object graph)
     {
@@ -30,7 +30,7 @@ public static void Serialize(TextWriter writer, object graph, string comments)
                 writer.WriteLine(comment.TrimEnd('\r'));
             }
         }
-        serializer.Value.Serialize(writer, graph);
+        serializer.Serialize(writer, graph);
     }
 
     public static void Serialize(string path, object graph, string comments)
@@ -41,7 +41,7 @@ public static void Serialize(string path, object graph, string comments)
 
     public static T Deserialize<T>(TextReader reader)
     {
-        return deserializer.Value.Deserialize<T>(reader);
+        return deserializer.Deserialize<T>(reader);
     }
 
     public static T Deserialize<T>(string path)
@@ -55,8 +55,8 @@ public static T ConvertTo<T>(object obj)
         var sb = new StringBuilder();
         using (var writer = new StringWriter(sb))
         {
-            serializer.Value.Serialize(writer, obj);
+            serializer.Serialize(writer, obj);
         }
-        return deserializer.Value.Deserialize<T>(new StringReader(sb.ToString()));
+        return deserializer.Deserialize<T>(new StringReader(sb.ToString()));
     }
 }

src/Docfx.Dotnet/DotnetApiCatalog.cs

@@ -15,6 +15,8 @@ namespace Docfx.Dotnet;
 /// </summary>
 public static partial class DotnetApiCatalog
 {
+    private static IDeserializer deserializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization().Build();
+
     /// <summary>
     /// Generates metadata reference YAML files using docfx.json config.
     /// </summary>
@@ -96,13 +98,12 @@ void WriteMarkdown(string outputFolder, string id, Build.ApiPage.ApiPage apiPage
                     break;
 
                 case MetadataOutputFormat.ApiPage:
-                    var serializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization().Build();
                     CreatePages(WriteYaml, assemblies, config, options);
 
                     void WriteYaml(string outputFolder, string id, Build.ApiPage.ApiPage apiPage)
                     {
                         var json = JsonSerializer.Serialize(apiPage, Docfx.Build.ApiPage.ApiPage.JsonSerializerOptions);
-                        var obj = serializer.Deserialize(json);
+                        var obj = deserializer.Deserialize(json);
                         YamlUtility.Serialize(Path.Combine(outputFolder, $"{id}.yml"), obj, "YamlMime:ApiPage");
                     }
                     break;

src/Docfx.YamlSerialization/NodeDeserializers/EmitGenericCollectionNodeDeserializer.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Collections.Concurrent;
 using System.Reflection;
 using System.Reflection.Emit;
 using Docfx.YamlSerialization.Helpers;
@@ -20,9 +21,9 @@ public class EmitGenericCollectionNodeDeserializer : INodeDeserializer
     private readonly IObjectFactory _objectFactory;
     private readonly INamingConvention _enumNamingConvention;
     private readonly ITypeInspector _typeDescriptor;
-    private readonly Dictionary<Type, Type?> _gpCache =
+    private readonly ConcurrentDictionary<Type, Type?> _gpCache =
         new();
-    private readonly Dictionary<Type, Action<IParser, Type, Func<IParser, Type, object?>, object?, INamingConvention, ITypeInspector>> _actionCache =
+    private readonly ConcurrentDictionary<Type, Action<IParser, Type, Func<IParser, Type, object?>, object?, INamingConvention, ITypeInspector>> _actionCache =
         new();
 
     public EmitGenericCollectionNodeDeserializer(IObjectFactory objectFactory, INamingConvention enumNamingConvention, ITypeInspector typeDescriptor)

src/Docfx.YamlSerialization/NodeDeserializers/EmitGenericDictionaryNodeDeserializer.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Collections.Concurrent;
 using System.ComponentModel;
 using System.Reflection;
 using System.Reflection.Emit;
@@ -16,8 +17,8 @@ public class EmitGenericDictionaryNodeDeserializer : INodeDeserializer
     private static readonly MethodInfo DeserializeHelperMethod =
         typeof(EmitGenericDictionaryNodeDeserializer).GetMethod(nameof(DeserializeHelper))!;
     private readonly IObjectFactory _objectFactory;
-    private readonly Dictionary<Type, Type[]?> _gpCache = [];
-    private readonly Dictionary<Tuple<Type, Type>, Action<IParser, Type, Func<IParser, Type, object?>, object?>> _actionCache = [];
+    private readonly ConcurrentDictionary<Type, Type[]?> _gpCache = [];
+    private readonly ConcurrentDictionary<Tuple<Type, Type>, Action<IParser, Type, Func<IParser, Type, object?>, object?>> _actionCache = [];
 
     public EmitGenericDictionaryNodeDeserializer(IObjectFactory objectFactory)
     {

src/Docfx.YamlSerialization/ObjectFactories/DefaultEmitObjectFactory.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Collections.Concurrent;
 using System.Reflection;
 using System.Reflection.Emit;
 
@@ -10,7 +11,7 @@ namespace Docfx.YamlSerialization.ObjectFactories;
 
 public class DefaultEmitObjectFactory : ObjectFactoryBase
 {
-    private readonly Dictionary<Type, Func<object>> _cache = [];
+    private readonly ConcurrentDictionary<Type, Func<object>> _cache = [];
     private static Type[] EmptyTypes => Type.EmptyTypes;
 
     public override object Create(Type type)

src/Docfx.YamlSerialization/ObjectGraphTraversalStrategies/FullObjectGraphTraversalStrategy.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections;
+using System.Collections.Concurrent;
 using System.ComponentModel;
 using System.Diagnostics;
 using System.Reflection;
@@ -32,7 +33,7 @@ public class FullObjectGraphTraversalStrategy : IObjectGraphTraversalStrategy
     private readonly IObjectFactory _objectFactory;
 
     // private readonly Dictionary<Tuple<Type, Type>, Action<IPropertyDescriptor?, IObjectDescriptor, IObjectGraphVisitor, Type, Type, IObjectGraphVisitorContext, Stack<FullObjectGraphTraversalStrategy.ObjectPathSegment>, ObjectSerializer>> _behaviorCache = new();
-    private readonly Dictionary<Tuple<Type, Type, Type>, Action<FullObjectGraphTraversalStrategy, object, IObjectGraphVisitor, INamingConvention, IObjectGraphVisitorContext, Stack<ObjectPathSegment>, ObjectSerializer>> _traverseGenericDictionaryCache = new();
+    private readonly ConcurrentDictionary<Tuple<Type, Type, Type>, Action<FullObjectGraphTraversalStrategy, object, IObjectGraphVisitor, INamingConvention, IObjectGraphVisitorContext, Stack<ObjectPathSegment>, ObjectSerializer>> _traverseGenericDictionaryCache = new();
 
     protected YamlSerializer Serializer { get; }
 

src/Docfx.YamlSerialization/YamlSerializer.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Collections.Concurrent;
 using Docfx.YamlSerialization.Helpers;
 using Docfx.YamlSerialization.ObjectDescriptors;
 using Docfx.YamlSerialization.ObjectGraphTraversalStrategies;
@@ -141,7 +142,7 @@ private IEventEmitter CreateEventEmitter()
         {
             return new TypeAssigningEventEmitter(
                 writer,
-                new Dictionary<Type, TagName>(),
+                new ConcurrentDictionary<Type, TagName>(),
                 quoteNecessaryStrings: false,
                 quoteYaml1_1Strings: false,
                 defaultScalarStyle: ScalarStyle.Any,

test/docfx.Tests/SerializationTests/YamlSerializationTest.ApiPage.cs

@@ -12,6 +12,8 @@ namespace docfx.Tests;
 
 public partial class YamlSerializationTest
 {
+    private static IDeserializer deserializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization().Build();
+
     [Theory]
     [TestData<ApiPage>]
     public void YamlSerializationTest_ApiPage(string path)
@@ -30,9 +32,6 @@ private static ApiPage LoadApiPage(string path)
     {
         path = PathHelper.ResolveTestDataPath(path);
 
-        var deserializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization()
-                                                    .Build();
-
         // 1. Deserialize ApiPage yaml as Dictionary
         // 2. Serialize to json
         // 3. Deserialize as ApiPage instance
@@ -56,8 +55,6 @@ private static void ValidateApiPageRoundTrip(ApiPage model)
 
     private static string ToYaml(ApiPage model)
     {
-        var deserializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization().Build();
-
         var json = JsonSerializer.Serialize(model, Docfx.Build.ApiPage.ApiPage.JsonSerializerOptions);
         var obj = deserializer.Deserialize(json);
 
@@ -68,7 +65,6 @@ private static string ToYaml(ApiPage model)
 
     private static ApiPage ToApiPage(string yaml)
     {
-        var deserializer = new DeserializerBuilder().WithAttemptingUnquotedStringTypeDeserialization().Build();
         var dict = deserializer.Deserialize<Dictionary<object, object>>(new StringReader(yaml));
         var json = JsonSerializer.Serialize(dict);
         return JsonSerializer.Deserialize<ApiPage>(json, ApiPage.JsonSerializerOptions);