From 4241ac5de4f9ed5c3af780efc642331a86ff894a Mon Sep 17 00:00:00 2001
From: Markus Hartung <mail@hartmark.se>
Date: Wed, 25 Jan 2023 00:37:31 +0100
Subject: [PATCH] Fix decoding/encoding payloads with attribute decoration #456

---
 src/JWT/Builder/JwtBuilder.cs                 | 34 ++++++++++++-
 src/JWT/JWT.csproj                            |  2 +-
 .../Builder/JwtBuilderDecodeTests.cs          | 48 +++++++++++++++++++
 tests/JWT.Tests.Common/Models/TestData.cs     | 14 ++++++
 4 files changed, 96 insertions(+), 2 deletions(-)

diff --git a/src/JWT/Builder/JwtBuilder.cs b/src/JWT/Builder/JwtBuilder.cs
index 36f6c61f4..3d486ec80 100644
--- a/src/JWT/Builder/JwtBuilder.cs
+++ b/src/JWT/Builder/JwtBuilder.cs
@@ -3,6 +3,7 @@
 using System.Reflection;
 using JWT.Algorithms;
 using JWT.Serializers;
+using Newtonsoft.Json;
 using static JWT.Internal.EncodingHelper;
 
 namespace JWT.Builder
@@ -276,7 +277,7 @@ public string Encode(Type payloadType, object payload)
             EnsureCanEncode();
 
             var dic = payloadType.GetProperties(BindingFlags.Instance | BindingFlags.Public)
-                                 .ToDictionary(prop => prop.Name, prop => prop.GetValue(payload, null));
+                                 .ToDictionary(info => GetPropName(info, _jsonSerializerFactory), prop => prop.GetValue(payload, null));
 
             foreach (var pair in dic)
             {
@@ -286,6 +287,37 @@ public string Encode(Type payloadType, object payload)
             return Encode();
         }
 
+        private static string GetPropName(MemberInfo prop, IJsonSerializerFactory jsonSerializerFactory)
+        {
+            var customAttributes = prop.GetCustomAttributes(true);
+            foreach (var attribute in customAttributes)
+            {
+                if (jsonSerializerFactory.Create() is JsonNetSerializer)
+                {
+                    if (attribute is JsonPropertyAttribute jsonNetProperty)
+                    {
+                        return jsonNetProperty.PropertyName;
+                    }
+                }
+#if MODERN_DOTNET
+                else if (jsonSerializerFactory.Create() is SystemTextSerializer)
+                {
+                    if (attribute is System.Text.Json.Serialization.JsonPropertyNameAttribute systemTextSerializerProperty)
+                    {
+                        return systemTextSerializerProperty.Name;
+                    }
+                }
+#endif
+                else
+                {
+                    throw new NotSupportedException(
+                        $"{jsonSerializerFactory.Create().GetType().Name} is not supported");
+                }
+            }
+            
+            return prop.Name;
+        }
+
         /// <summary>
         /// Decodes a token using the supplied dependencies.
         /// </summary>
diff --git a/src/JWT/JWT.csproj b/src/JWT/JWT.csproj
index 7513c1e4a..9038b73e5 100644
--- a/src/JWT/JWT.csproj
+++ b/src/JWT/JWT.csproj
@@ -20,7 +20,7 @@
     <Authors>Alexander Batishchev, John Sheehan, Michael Lehenbauer</Authors>
     <PackageTags>jwt;json;authorization</PackageTags>
     <PackageLicenseExpression>CC0-1.0</PackageLicenseExpression>
-    <Version>10.0.1</Version>
+    <Version>10.0.2</Version>
     <FileVersion>10.0.0.0</FileVersion>
     <AssemblyVersion>10.0.0.0</AssemblyVersion>
     <RootNamespace>JWT</RootNamespace>
diff --git a/tests/JWT.Tests.Common/Builder/JwtBuilderDecodeTests.cs b/tests/JWT.Tests.Common/Builder/JwtBuilderDecodeTests.cs
index dbafb02cf..f67bd0082 100644
--- a/tests/JWT.Tests.Common/Builder/JwtBuilderDecodeTests.cs
+++ b/tests/JWT.Tests.Common/Builder/JwtBuilderDecodeTests.cs
@@ -433,5 +433,53 @@ public void Decode_ToDictionary_Without_Serializer_Should_Throw_Exception()
             action.Should()
                   .Throw<ArgumentNullException>();
         }
+        
+        [TestMethod]
+        public void Encode_Decode_ToJsonNetDecoratedType_Should_UseDecoratedName_Bug456()
+        {
+            var token = JwtBuilder.Create()
+                .WithAlgorithm(new NoneAlgorithm())
+                .WithJsonSerializer(new JsonNetSerializer());
+
+            var model = new TestData.TestDataJsonNetDecorated
+            {
+                AccessToken = "abc123",
+            };
+            
+            var encoded = token.Encode(model);
+            Assert.IsNotNull(encoded);
+
+            token = JwtBuilder.Create()
+                .WithAlgorithm(new NoneAlgorithm())
+                .WithJsonSerializer(new JsonNetSerializer());
+
+            var payloadDecoded = token.Decode<TestData.TestDataJsonNetDecorated>(encoded);
+            Assert.AreEqual(model.AccessToken, payloadDecoded.AccessToken);
+        }
+#if NETSTANDARD2_0 || NET6_0 || NET7_0
+
+        [TestMethod]
+        public void Encode_Decode_ToSystemTextSerializerDecoratedType_Should_UseDecoratedName_Bug456()
+        {
+            var token = JwtBuilder.Create()
+                .WithAlgorithm(new NoneAlgorithm())
+                .WithJsonSerializer(new SystemTextSerializer());
+
+            var model = new TestData.TestDataSystemTextSerializerDecorated
+            {
+                AccessToken = "abc123",
+            };
+            
+            var encoded = token.Encode(model);
+            Assert.IsNotNull(encoded);
+
+            token = JwtBuilder.Create()
+                .WithAlgorithm(new NoneAlgorithm())
+                .WithJsonSerializer(new SystemTextSerializer());
+
+            var payloadDecoded = token.Decode<TestData.TestDataSystemTextSerializerDecorated>(encoded);
+            Assert.AreEqual(model.AccessToken, payloadDecoded.AccessToken);
+        }
+#endif
     }
 }
diff --git a/tests/JWT.Tests.Common/Models/TestData.cs b/tests/JWT.Tests.Common/Models/TestData.cs
index 94da079e8..9ffeb270a 100644
--- a/tests/JWT.Tests.Common/Models/TestData.cs
+++ b/tests/JWT.Tests.Common/Models/TestData.cs
@@ -17,6 +17,20 @@ public static class TestData
             Age = 33
         };
 
+        public class TestDataJsonNetDecorated
+        {
+            [Newtonsoft.Json.JsonProperty("AT")]
+            public string AccessToken { get; set; }
+        }
+        
+#if NETSTANDARD2_0 || NET6_0 || NET7_0
+        public class TestDataSystemTextSerializerDecorated
+        {
+            [System.Text.Json.Serialization.JsonPropertyName("AT")]
+            public string AccessToken { get; set; }
+        }
+#endif
+        
         public const string Secret = "GQDstcKsx0NHjPOuXOYg5MbeJ1XT0uFiwDVvVBrk";
         public const string Secret2 = "QWORIJkmQWEDIHbjhOIHAUSDFOYnUGWEYT";