some fixes

Author: dmitry-bym

JsonKnownTypes.sln

@@ -7,6 +7,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "JsonKnownTypes", "src\JsonK
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "JsonKnownTypes.UnitTests", "tests\JsonKnownTypes.UnitTests\JsonKnownTypes.UnitTests.csproj", "{3DE82BA5-F66A-4E39-AC18-427D22778E32}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "JsonKnownTypes.Benchmark", "tests\JsonKnownTypes.Benchmark\JsonKnownTypes.Benchmark.csproj", "{F8736333-CFCC-4C27-9199-7EC2134AE462}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -21,6 +23,10 @@ Global
 		{3DE82BA5-F66A-4E39-AC18-427D22778E32}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{3DE82BA5-F66A-4E39-AC18-427D22778E32}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{3DE82BA5-F66A-4E39-AC18-427D22778E32}.Release|Any CPU.Build.0 = Release|Any CPU
+		{F8736333-CFCC-4C27-9199-7EC2134AE462}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{F8736333-CFCC-4C27-9199-7EC2134AE462}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{F8736333-CFCC-4C27-9199-7EC2134AE462}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{F8736333-CFCC-4C27-9199-7EC2134AE462}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

README.md

@@ -1,5 +1,5 @@
 # JsonKnownTypes .Net Standard
-[![nuget](https://img.shields.io/badge/nuget-v0.4.0-orange?style=flat-square)](https://www.nuget.org/packages/JsonKnownTypes)
+[![nuget](https://img.shields.io/badge/nuget-v0.4.1-orange?style=flat-square)](https://www.nuget.org/packages/JsonKnownTypes)
 [![downloads](https://img.shields.io/nuget/dt/JsonKnownTypes?style=flat-square)](https://www.nuget.org/packages/JsonKnownTypes)
 [![lisence](https://img.shields.io/badge/lisence-MIT-green?style=flat-square)](https://github.com/dmitry-bym/JsonKnownTypes/blob/master/LICENSE)
 

resources/json.net.png

@@ -1,7 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
-using System.Linq.Expressions;
 using JsonKnownTypes.Exceptions;
 
 namespace JsonKnownTypes
@@ -11,14 +9,12 @@ internal class DiscriminatorValues
         public string FieldName { get; }
         private Dictionary<string, Type> DiscriminatorToType { get; }
         private Dictionary<Type, string> TypeToDiscriminator { get; }
-        private Dictionary<Type, Func<object>> TypeToConstructor { get; }
 
         public DiscriminatorValues(string fieldName)
         {
             FieldName = fieldName;
             DiscriminatorToType = new Dictionary<string, Type>();
             TypeToDiscriminator = new Dictionary<Type, string>();
-            TypeToConstructor = new Dictionary<Type, Func<object>>();
         }
 
         public int Count
@@ -46,25 +42,8 @@ public void AddType(Type type, string discriminator)
             if (DiscriminatorToType.ContainsKey(discriminator))
                 throw new JsonKnownTypesException($"{discriminator} discriminator already in use");
 
-            TypeToConstructor.Add(type, GenerateConstructor(type));
             TypeToDiscriminator.Add(type, discriminator);
             DiscriminatorToType.Add(discriminator, type);
         }
-
-        
-        public object CreateInstance(Type type) 
-            => TypeToConstructor[type]();
-
-        private static Func<object> GenerateConstructor(Type type)
-        {
-            var constructor = type.GetConstructors().FirstOrDefault(x => x.GetParameters().Length == 0) 
-                      ?? throw new JsonKnownTypesException($"{type.Name} type has no constructor without parameters");
-
-            var newExpr = Expression.New(constructor);
-
-            var convertExpr = Expression.Convert(newExpr, typeof(object));
-            var lambda = Expression.Lambda<Func<object>>(convertExpr);
-            return lambda.Compile();
-        }
     }
 }

resources/v0.3.0.png

@@ -10,7 +10,7 @@
 
   <PropertyGroup>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
-    <Version>0.4.0</Version>
+    <Version>0.4.1</Version>
     <Authors>Dmitry Kaznacheev</Authors>
     <PackageProjectUrl>https://github.com/dmitry-bym/JsonKnownTypes</PackageProjectUrl>
     <PackageLicenseUrl>https://github.com/dmitry-bym/JsonKnownTypes/blob/master/LICENSE</PackageLicenseUrl>

resources/v0.4.1.png

@@ -17,6 +17,10 @@ private readonly DiscriminatorValues _typesDiscriminatorValues
         public override bool CanConvert(Type objectType)
             => _typesDiscriminatorValues.Contains(objectType);
 
+        private readonly ThreadLocal<bool> _isInRead = new ThreadLocal<bool>();
+
+        public override bool CanRead { get => !_isInRead.Value; }
+
         public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
         {
             if (reader.TokenType == JsonToken.Null) return null;
@@ -31,10 +35,14 @@ public override object ReadJson(JsonReader reader, Type objectType, object exist
             if (_typesDiscriminatorValues.TryGetType(discriminator, out var typeForObject))
             {
                 var jsonReader = jObject.CreateReader();
-                var target = _typesDiscriminatorValues.CreateInstance(typeForObject);
+                
+                _isInRead.Value = true;
+
+                var obj = serializer.Deserialize(jsonReader, typeForObject);
 
-                serializer.Populate(jsonReader, target);
-                return target;
+                _isInRead.Value = false;
+                
+                return obj;
             }
 
             throw new JsonKnownTypesException($"{discriminator} discriminator is not registered for {nameof(T)} type");

src/JsonKnownTypes/DiscriminatorValues.cs

@@ -6,12 +6,12 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="AutoFixture" Version="4.11.0" />
     <PackageReference Include="BenchmarkDotNet" Version="0.12.1" />
   </ItemGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\src\JsonKnownTypes\JsonKnownTypes.csproj" />
-    <ProjectReference Include="..\tests\JsonKnownTypes.UnitTests\JsonKnownTypes.UnitTests.csproj" />
+    <ProjectReference Include="..\..\src\JsonKnownTypes\JsonKnownTypes.csproj" />
   </ItemGroup>
 
 </Project>