Added more options for... options on JsonStringEnumMemberConverter.

Author: CodeBlanch

ClassLibraries/Macross.Json.Extensions/CHANGELOG.md

@@ -11,6 +11,15 @@
   `JsonStringEnumMemberConverter`. See the project [README](./README.md) for
   details on its usage.
 
+* Added a constructor on `JsonStringEnumMemberConverter` which accepts
+  `JsonStringEnumMemberConverterOptions options` & `params Type[]
+  targetEnumTypes` parameters for specifying the options to be used to
+  serialize/deserialize the specific target enum types.
+
+* Added `JsonStringEnumMemberConverterOptionsAttribute` which can be used to
+  decorate an enum type with the options to use when serializing/deserializing
+  its values.
+
 ## 2.0.0
 
 * `JsonMicrosoftDateTimeConverter` & `JsonMicrosoftDateTimeOffsetConverter` now

ClassLibraries/Macross.Json.Extensions/Code/Macross.Json.Extensions.csproj

@@ -24,7 +24,7 @@
     <GenerateAssemblyVersionAttribute>false</GenerateAssemblyVersionAttribute>
     <GeneratePackageOnBuild>false</GeneratePackageOnBuild>
     <VersionPrefix>2.1.0</VersionPrefix>
-    <VersionSuffix>beta1</VersionSuffix>
+    <VersionSuffix>beta2</VersionSuffix>
     <FileVersion>$(VersionPrefix)</FileVersion>
     <PackageProjectUrl>https://github.com/Macross-Software/core/tree/develop/ClassLibraries/Macross.Json.Extensions</PackageProjectUrl>
   </PropertyGroup>

ClassLibraries/Macross.Json.Extensions/Code/Properties/AssemblyInfo.cs

@@ -1,10 +1,13 @@
 using System;
 using System.Reflection;
+using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 
 [assembly: ComVisible(false)]
 [assembly: CLSCompliant(false)]
 
 [assembly: Guid("46de8812-8b05-40b9-8012-7702f9f31506")]
 
-[assembly: AssemblyVersion("2.1.0.21073")]
+[assembly: InternalsVisibleTo("Macross.Json.Extensions.Tests, PublicKey=002400000480000094000000060200000024000052534131000400000100010051b7a480b13cecfa44862449486c6884bd6168c325445a0848f48deca9643657c5ae85df3cf6ffdb24d5bd3e9b71dc074ca602544b83511fbce1f83f1d06bb8b7b564414c9d8c719e4e39b95643dfc8e9ce997b5e2a1542a8ff6379186f87b8b695fee82c506170c4fb8ffcbf2e68f4b5d270083f8909c67916500608ce747e9")]
+
+[assembly: AssemblyVersion("2.1.0.21074")]

ClassLibraries/Macross.Json.Extensions/Code/System.Text.Json.Serialization/JsonStringEnumMemberConverter.cs

@@ -1,4 +1,5 @@
-using System.Reflection;
+using System.Collections.Generic;
+using System.Reflection;
 using System.Runtime.Serialization;
 
 namespace System.Text.Json.Serialization
@@ -8,15 +9,13 @@ namespace System.Text.Json.Serialization
 	/// </summary>
 	public class JsonStringEnumMemberConverter : JsonConverterFactory
 	{
-		private readonly JsonNamingPolicy? _NamingPolicy;
-		private readonly bool _AllowIntegerValues;
-		private readonly ulong? _DeserializationFailureFallbackValue;
+		private readonly HashSet<Type>? _EnumTypes;
+		private readonly JsonStringEnumMemberConverterOptions? _Options;
 
 		/// <summary>
 		/// Initializes a new instance of the <see cref="JsonStringEnumMemberConverter"/> class.
 		/// </summary>
 		public JsonStringEnumMemberConverter()
-			: this(namingPolicy: null, allowIntegerValues: true)
 		{
 		}
 
@@ -30,46 +29,91 @@ public JsonStringEnumMemberConverter()
 		/// True to allow undefined enum values. When true, if an enum value isn't
 		/// defined it will output as a number rather than a string.
 		/// </param>
-		/// <param name="deserializationFailureFallbackValue">
-		/// Optional default value to use when a json string does not match
-		/// anything defined on the target enum. If not specified a <see
-		/// cref="JsonException"/> is thrown for all failures.
-		/// </param>
-		public JsonStringEnumMemberConverter(JsonNamingPolicy? namingPolicy = null, bool allowIntegerValues = true, ulong? deserializationFailureFallbackValue = null)
+		public JsonStringEnumMemberConverter(JsonNamingPolicy? namingPolicy = null, bool allowIntegerValues = true)
+			: this(new JsonStringEnumMemberConverterOptions { NamingPolicy = namingPolicy, AllowIntegerValues = allowIntegerValues })
 		{
-			_NamingPolicy = namingPolicy;
-			_AllowIntegerValues = allowIntegerValues;
-			_DeserializationFailureFallbackValue = deserializationFailureFallbackValue;
 		}
 
+		/// <summary>
+		/// Initializes a new instance of the <see cref="JsonStringEnumMemberConverter"/> class.
+		/// </summary>
+		/// <param name="options"><see cref="JsonStringEnumMemberConverterOptions"/>.</param>
+		/// <param name="targetEnumTypes">Optional list of supported enum types to be converted. Specify <see langword="null"/> or empty to convert all enums.</param>
+		public JsonStringEnumMemberConverter(JsonStringEnumMemberConverterOptions options, params Type[] targetEnumTypes)
+		{
+			_Options = options ?? throw new ArgumentNullException(nameof(options));
+
+			if (targetEnumTypes != null && targetEnumTypes.Length > 0)
+			{
+#if NETSTANDARD2_0
+				_EnumTypes = new HashSet<Type>();
+#else
+				_EnumTypes = new HashSet<Type>(targetEnumTypes.Length);
+#endif
+				foreach (Type enumType in targetEnumTypes)
+				{
+					if (enumType.IsEnum)
+					{
+						_EnumTypes.Add(enumType);
+						_EnumTypes.Add(typeof(Nullable<>).MakeGenericType(enumType));
+						continue;
+					}
+
+					if (enumType.IsGenericType)
+					{
+						(bool IsNullableEnum, Type? UnderlyingType) = TestNullableEnum(enumType);
+						if (IsNullableEnum)
+						{
+							_EnumTypes.Add(UnderlyingType!);
+							_EnumTypes.Add(enumType);
+							continue;
+						}
+					}
+
+					throw new NotSupportedException($"Type {enumType} is not supported by JsonStringEnumMemberConverter. Only enum types can be converted.");
+				}
+			}
+		}
+
+#pragma warning disable CA1062 // Validate arguments of public methods
 		/// <inheritdoc/>
 		public override bool CanConvert(Type typeToConvert)
 		{
 			// Don't perform a typeToConvert == null check for performance. Trust our callers will be nice.
-#pragma warning disable CA1062 // Validate arguments of public methods
-			return typeToConvert.IsEnum
+			return _EnumTypes != null
+				? _EnumTypes.Contains(typeToConvert)
+				: typeToConvert.IsEnum
 				|| (typeToConvert.IsGenericType && TestNullableEnum(typeToConvert).IsNullableEnum);
-#pragma warning restore CA1062 // Validate arguments of public methods
 		}
+#pragma warning restore CA1062 // Validate arguments of public methods
 
 		/// <inheritdoc/>
 		public override JsonConverter CreateConverter(Type typeToConvert, JsonSerializerOptions options)
 		{
 			(bool IsNullableEnum, Type? UnderlyingType) = TestNullableEnum(typeToConvert);
 
-			return IsNullableEnum
-				? (JsonConverter)Activator.CreateInstance(
-					typeof(NullableEnumMemberConverter<>).MakeGenericType(UnderlyingType),
-					BindingFlags.Instance | BindingFlags.Public,
-					binder: null,
-					args: new object?[] { _NamingPolicy, _AllowIntegerValues, _DeserializationFailureFallbackValue },
-					culture: null)
-				: (JsonConverter)Activator.CreateInstance(
-					typeof(EnumMemberConverter<>).MakeGenericType(typeToConvert),
-					BindingFlags.Instance | BindingFlags.Public,
-					binder: null,
-					args: new object?[] { _NamingPolicy, _AllowIntegerValues, _DeserializationFailureFallbackValue },
-					culture: null);
+			try
+			{
+				return IsNullableEnum
+					? (JsonConverter)Activator.CreateInstance(
+						typeof(NullableEnumMemberConverter<>).MakeGenericType(UnderlyingType),
+						BindingFlags.Instance | BindingFlags.Public,
+						binder: null,
+						args: new object?[] { _Options },
+						culture: null)
+					: (JsonConverter)Activator.CreateInstance(
+						typeof(EnumMemberConverter<>).MakeGenericType(typeToConvert),
+						BindingFlags.Instance | BindingFlags.Public,
+						binder: null,
+						args: new object?[] { _Options },
+						culture: null);
+			}
+			catch (TargetInvocationException targetInvocationEx)
+			{
+				if (targetInvocationEx.InnerException != null)
+					throw targetInvocationEx.InnerException;
+				throw;
+			}
 		}
 
 		private static (bool IsNullableEnum, Type? UnderlyingType) TestNullableEnum(Type typeToConvert)
@@ -79,16 +123,32 @@ private static (bool IsNullableEnum, Type? UnderlyingType) TestNullableEnum(Type
 			return (UnderlyingType?.IsEnum ?? false, UnderlyingType);
 		}
 
+		internal static ulong GetEnumValue(TypeCode enumTypeCode, object value)
+		{
+			return enumTypeCode switch
+			{
+				TypeCode.Int32 => (ulong)(int)value,
+				TypeCode.Int64 => (ulong)(long)value,
+				TypeCode.Int16 => (ulong)(short)value,
+				TypeCode.Byte => (byte)value,
+				TypeCode.UInt32 => (uint)value,
+				TypeCode.UInt64 => (ulong)value,
+				TypeCode.UInt16 => (ushort)value,
+				TypeCode.SByte => (ulong)(sbyte)value,
+				_ => throw new NotSupportedException($"Enum '{value}' of {enumTypeCode} type is not supported."),
+			};
+		}
+
 #pragma warning disable CA1812 // Remove class never instantiated
 		private class EnumMemberConverter<TEnum> : JsonConverter<TEnum>
 			where TEnum : struct, Enum
 #pragma warning restore CA1812 // Remove class never instantiated
 		{
 			private readonly JsonStringEnumMemberConverterHelper<TEnum> _JsonStringEnumMemberConverterHelper;
 
-			public EnumMemberConverter(JsonNamingPolicy? namingPolicy, bool allowIntegerValues, ulong? deserializationFailureFallbackValue)
+			public EnumMemberConverter(JsonStringEnumMemberConverterOptions? options)
 			{
-				_JsonStringEnumMemberConverterHelper = new JsonStringEnumMemberConverterHelper<TEnum>(namingPolicy, allowIntegerValues, deserializationFailureFallbackValue);
+				_JsonStringEnumMemberConverterHelper = new JsonStringEnumMemberConverterHelper<TEnum>(options);
 			}
 
 			public override TEnum Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
@@ -105,9 +165,9 @@ private class NullableEnumMemberConverter<TEnum> : JsonConverter<TEnum?>
 		{
 			private readonly JsonStringEnumMemberConverterHelper<TEnum> _JsonStringEnumMemberConverterHelper;
 
-			public NullableEnumMemberConverter(JsonNamingPolicy? namingPolicy, bool allowIntegerValues, ulong? deserializationFailureFallbackValue)
+			public NullableEnumMemberConverter(JsonStringEnumMemberConverterOptions? options)
 			{
-				_JsonStringEnumMemberConverterHelper = new JsonStringEnumMemberConverterHelper<TEnum>(namingPolicy, allowIntegerValues, deserializationFailureFallbackValue);
+				_JsonStringEnumMemberConverterHelper = new JsonStringEnumMemberConverterHelper<TEnum>(options);
 			}
 
 			public override TEnum? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)

ClassLibraries/Macross.Json.Extensions/Code/System.Text.Json.Serialization/JsonStringEnumMemberConverterHelper.cs

@@ -41,13 +41,20 @@ public EnumInfo(string name, TEnum enumValue, ulong rawValue)
 		private readonly Dictionary<TEnum, EnumInfo> _RawToTransformed;
 		private readonly Dictionary<string, EnumInfo> _TransformedToRaw;
 
-		public JsonStringEnumMemberConverterHelper(JsonNamingPolicy? namingPolicy, bool allowIntegerValues, ulong? deserializationFailureFallbackValue)
+		public JsonStringEnumMemberConverterHelper(JsonStringEnumMemberConverterOptions? options)
 		{
-			_AllowIntegerValues = allowIntegerValues;
 			_EnumType = typeof(TEnum);
+
+			JsonStringEnumMemberConverterOptions? computedOptions
+				= _EnumType.GetCustomAttribute<JsonStringEnumMemberConverterOptionsAttribute>(false)?.Options
+				?? options;
+
+			_AllowIntegerValues = computedOptions?.AllowIntegerValues ?? true;
 			_EnumTypeCode = Type.GetTypeCode(_EnumType);
 			_IsFlags = _EnumType.IsDefined(typeof(FlagsAttribute), true);
 
+			ulong? deserializationFailureFallbackValue = computedOptions?.ConvertedDeserializationFailureFallbackValue;
+
 			string[] builtInNames = _EnumType.GetEnumNames();
 			Array builtInValues = _EnumType.GetEnumValues();
 
@@ -59,14 +66,14 @@ public JsonStringEnumMemberConverterHelper(JsonNamingPolicy? namingPolicy, bool
 				Enum? enumValue = (Enum?)builtInValues.GetValue(i);
 				if (enumValue == null)
 					continue;
-				ulong rawValue = GetEnumValue(enumValue);
+				ulong rawValue = JsonStringEnumMemberConverter.GetEnumValue(_EnumTypeCode, enumValue);
 
 				string name = builtInNames[i];
 				FieldInfo field = _EnumType.GetField(name, EnumBindings)!;
 
 				string transformedName = field.GetCustomAttribute<EnumMemberAttribute>(true)?.Value ??
 										 field.GetCustomAttribute<JsonPropertyNameAttribute>(true)?.Name ??
-										 namingPolicy?.ConvertName(name) ??
+										 computedOptions?.NamingPolicy?.ConvertName(name) ??
 										 name;
 
 				if (enumValue is not TEnum typedValue)
@@ -78,6 +85,9 @@ public JsonStringEnumMemberConverterHelper(JsonNamingPolicy? namingPolicy, bool
 				_RawToTransformed[typedValue] = new EnumInfo(transformedName, typedValue, rawValue);
 				_TransformedToRaw[transformedName] = new EnumInfo(name, typedValue, rawValue);
 			}
+
+			if (deserializationFailureFallbackValue.HasValue && !_DeserializationFailureFallbackValue.HasValue)
+				throw new JsonException($"JsonStringEnumMemberConverter could not find a definition on Enum type {_EnumType} matching deserializationFailureFallbackValue '{deserializationFailureFallbackValue}'.");
 		}
 
 		public TEnum Read(ref Utf8JsonReader reader)
@@ -220,7 +230,7 @@ public void Write(Utf8JsonWriter writer, TEnum value)
 				return;
 			}
 
-			ulong rawValue = GetEnumValue(value);
+			ulong rawValue = JsonStringEnumMemberConverter.GetEnumValue(_EnumTypeCode, value);
 
 			if (_IsFlags)
 			{
@@ -289,22 +299,6 @@ public void Write(Utf8JsonWriter writer, TEnum value)
 			}
 		}
 
-		private ulong GetEnumValue(object value)
-		{
-			return _EnumTypeCode switch
-			{
-				TypeCode.Int32 => (ulong)(int)value,
-				TypeCode.Int64 => (ulong)(long)value,
-				TypeCode.Int16 => (ulong)(short)value,
-				TypeCode.Byte => (byte)value,
-				TypeCode.UInt32 => (uint)value,
-				TypeCode.UInt64 => (ulong)value,
-				TypeCode.UInt16 => (ushort)value,
-				TypeCode.SByte => (ulong)(sbyte)value,
-				_ => throw new NotSupportedException($"Enum '{value}' of {_EnumTypeCode} type is not supported."),
-			};
-		}
-
 		[MethodImpl(MethodImplOptions.AggressiveInlining)]
 		private TEnum ReturnDefaultValueOrThrowJsonException(string propertyValue)
 			=> _DeserializationFailureFallbackValue ?? throw ThrowHelper.GenerateJsonException_DeserializeUnableToConvertValue(_EnumType, propertyValue);