From 4f0673b04b8fb4463778d4e57184ffcc2d5bfa96 Mon Sep 17 00:00:00 2001
From: martincostello <martin@martincostello.com>
Date: Tue, 29 Jul 2025 14:33:03 +0100
Subject: [PATCH] Update media type for JSON Patch

- Use `Content-Type: application/json-patch+json` for JSON patch.
- Fix some code analyzer suggestions.
- Fix broken `build.cmd` for JsonPatch.

Adapted from #62057.

Resolves #61956.
---
 .../src/JsonPatchDocument.cs                  | 29 ++++++++++-----
 .../src/JsonPatchDocumentOfT.cs               | 17 +++++++--
 ...AspNetCore.JsonPatch.SystemTextJson.csproj |  4 +++
 src/Features/JsonPatch/build.cmd              |  2 +-
 .../JsonPatch/src/JsonPatchDocument.cs        | 36 +++++++++++++++----
 .../JsonPatch/src/JsonPatchDocumentOfT.cs     | 28 ++++++++++++---
 .../src/Microsoft.AspNetCore.JsonPatch.csproj |  1 +
 .../sample/Endpoints/MapSchemasEndpoints.cs   |  2 ++
 src/OpenApi/sample/Sample.csproj              |  5 +--
 ...t_documentName=schemas-by-ref.verified.txt | 23 ++++++++++++
 ...t_documentName=schemas-by-ref.verified.txt | 23 ++++++++++++
 11 files changed, 145 insertions(+), 25 deletions(-)

diff --git a/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocument.cs b/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocument.cs
index c57febaff4e9..684ef7a8d28d 100644
--- a/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocument.cs
+++ b/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocument.cs
@@ -3,8 +3,11 @@
 
 using System;
 using System.Collections.Generic;
+using System.Reflection;
 using System.Text.Json;
 using System.Text.Json.Serialization;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Http.Metadata;
 using Microsoft.AspNetCore.JsonPatch.SystemTextJson.Adapters;
 using Microsoft.AspNetCore.JsonPatch.SystemTextJson.Converters;
 using Microsoft.AspNetCore.JsonPatch.SystemTextJson.Exceptions;
@@ -18,7 +21,7 @@ namespace Microsoft.AspNetCore.JsonPatch.SystemTextJson;
 // documents for cases where there's no class/DTO to work on. Typical use case: backend not built in
 // .NET or architecture doesn't contain a shared DTO layer.
 [JsonConverter(typeof(JsonPatchDocumentConverter))]
-public class JsonPatchDocument : IJsonPatchDocument
+public class JsonPatchDocument : IJsonPatchDocument, IEndpointParameterMetadataProvider
 {
     public List<Operation> Operations { get; private set; }
 
@@ -27,7 +30,7 @@ public class JsonPatchDocument : IJsonPatchDocument
 
     public JsonPatchDocument()
     {
-        Operations = new List<Operation>();
+        Operations = [];
         SerializerOptions = JsonSerializerOptions.Default;
     }
 
@@ -205,12 +208,13 @@ IList<Operation> IJsonPatchDocument.GetOperations()
         {
             foreach (var op in Operations)
             {
-                var untypedOp = new Operation();
-
-                untypedOp.op = op.op;
-                untypedOp.value = op.value;
-                untypedOp.path = op.path;
-                untypedOp.from = op.from;
+                var untypedOp = new Operation
+                {
+                    op = op.op,
+                    value = op.value,
+                    path = op.path,
+                    from = op.from
+                };
 
                 allOps.Add(untypedOp);
             }
@@ -218,4 +222,13 @@ IList<Operation> IJsonPatchDocument.GetOperations()
 
         return allOps;
     }
+
+    /// <inheritdoc/>
+    static void IEndpointParameterMetadataProvider.PopulateMetadata(ParameterInfo parameter, EndpointBuilder builder)
+    {
+        ArgumentNullException.ThrowIfNull(parameter);
+        ArgumentNullException.ThrowIfNull(builder);
+
+        builder.Metadata.Add(new AcceptsMetadata(["application/json-patch+json"], parameter.ParameterType));
+    }
 }
diff --git a/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocumentOfT.cs b/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocumentOfT.cs
index afb3f9ab0858..a9f1671ce8e6 100644
--- a/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocumentOfT.cs
+++ b/src/Features/JsonPatch.SystemTextJson/src/JsonPatchDocumentOfT.cs
@@ -9,6 +9,8 @@
 using System.Reflection;
 using System.Text.Json;
 using System.Text.Json.Serialization;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Http.Metadata;
 using Microsoft.AspNetCore.JsonPatch.SystemTextJson.Adapters;
 using Microsoft.AspNetCore.JsonPatch.SystemTextJson.Converters;
 using Microsoft.AspNetCore.JsonPatch.SystemTextJson.Exceptions;
@@ -23,7 +25,7 @@ namespace Microsoft.AspNetCore.JsonPatch.SystemTextJson;
 // including type data in the JsonPatchDocument serialized as JSON (to allow for correct deserialization) - that's
 // not according to RFC 6902, and would thus break cross-platform compatibility.
 [JsonConverter(typeof(JsonPatchDocumentConverterFactory))]
-public class JsonPatchDocument<TModel> : IJsonPatchDocument where TModel : class
+public class JsonPatchDocument<TModel> : IJsonPatchDocument, IEndpointParameterMetadataProvider where TModel : class
 {
     public List<Operation<TModel>> Operations { get; private set; }
 
@@ -32,7 +34,7 @@ public class JsonPatchDocument<TModel> : IJsonPatchDocument where TModel : class
 
     public JsonPatchDocument()
     {
-        Operations = new List<Operation<TModel>>();
+        Operations = [];
         SerializerOptions = JsonSerializerOptions.Default;
     }
 
@@ -657,11 +659,20 @@ IList<Operation> IJsonPatchDocument.GetOperations()
         return allOps;
     }
 
+    /// <inheritdoc/>
+    static void IEndpointParameterMetadataProvider.PopulateMetadata(ParameterInfo parameter, EndpointBuilder builder)
+    {
+        ArgumentNullException.ThrowIfNull(parameter);
+        ArgumentNullException.ThrowIfNull(builder);
+
+        builder.Metadata.Add(new AcceptsMetadata(["application/json-patch+json"], typeof(TModel)));
+    }
+
     // Internal for testing
     internal string GetPath<TProp>(Expression<Func<TModel, TProp>> expr, string position)
     {
         var segments = GetPathSegments(expr.Body);
-        var path = String.Join("/", segments);
+        var path = string.Join('/', segments);
         if (position != null)
         {
             path += "/" + position;
diff --git a/src/Features/JsonPatch.SystemTextJson/src/Microsoft.AspNetCore.JsonPatch.SystemTextJson.csproj b/src/Features/JsonPatch.SystemTextJson/src/Microsoft.AspNetCore.JsonPatch.SystemTextJson.csproj
index 8174fe7c0c92..434a8cf7373a 100644
--- a/src/Features/JsonPatch.SystemTextJson/src/Microsoft.AspNetCore.JsonPatch.SystemTextJson.csproj
+++ b/src/Features/JsonPatch.SystemTextJson/src/Microsoft.AspNetCore.JsonPatch.SystemTextJson.csproj
@@ -16,6 +16,10 @@
     <Compile Include="$(SharedSourceRoot)CallerArgument\CallerArgumentExpressionAttribute.cs" LinkBase="Shared" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Reference Include="Microsoft.AspNetCore.Http.Abstractions" />
+  </ItemGroup>
+
   <ItemGroup>
     <InternalsVisibleTo Include="Microsoft.AspNetCore.JsonPatch.SystemTextJson.Tests" />
   </ItemGroup>
diff --git a/src/Features/JsonPatch/build.cmd b/src/Features/JsonPatch/build.cmd
index 5274e00264f0..a71232783bb2 100644
--- a/src/Features/JsonPatch/build.cmd
+++ b/src/Features/JsonPatch/build.cmd
@@ -1,3 +1,3 @@
 @ECHO OFF
-SET RepoRoot=%~dp0..\..
+SET RepoRoot=%~dp0..\..\..
 %RepoRoot%\eng\build.cmd -projects %~dp0**\*.*proj %*
diff --git a/src/Features/JsonPatch/src/JsonPatchDocument.cs b/src/Features/JsonPatch/src/JsonPatchDocument.cs
index 5b9152ccdb12..e3f79c455806 100644
--- a/src/Features/JsonPatch/src/JsonPatchDocument.cs
+++ b/src/Features/JsonPatch/src/JsonPatchDocument.cs
@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Reflection;
 using Microsoft.AspNetCore.JsonPatch.Adapters;
 using Microsoft.AspNetCore.JsonPatch.Converters;
 using Microsoft.AspNetCore.JsonPatch.Exceptions;
@@ -12,13 +13,22 @@
 using Newtonsoft.Json;
 using Newtonsoft.Json.Serialization;
 
+#if NET
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Http.Metadata;
+#endif
+
 namespace Microsoft.AspNetCore.JsonPatch;
 
 // Implementation details: the purpose of this type of patch document is to allow creation of such
 // documents for cases where there's no class/DTO to work on. Typical use case: backend not built in
 // .NET or architecture doesn't contain a shared DTO layer.
 [JsonConverter(typeof(JsonPatchDocumentConverter))]
+#if NET
+public class JsonPatchDocument : IJsonPatchDocument, IEndpointParameterMetadataProvider
+#else
 public class JsonPatchDocument : IJsonPatchDocument
+#endif
 {
     public List<Operation> Operations { get; private set; }
 
@@ -27,7 +37,7 @@ public class JsonPatchDocument : IJsonPatchDocument
 
     public JsonPatchDocument()
     {
-        Operations = new List<Operation>();
+        Operations = [];
         ContractResolver = new DefaultContractResolver();
     }
 
@@ -205,12 +215,13 @@ IList<Operation> IJsonPatchDocument.GetOperations()
         {
             foreach (var op in Operations)
             {
-                var untypedOp = new Operation();
-
-                untypedOp.op = op.op;
-                untypedOp.value = op.value;
-                untypedOp.path = op.path;
-                untypedOp.from = op.from;
+                var untypedOp = new Operation
+                {
+                    op = op.op,
+                    value = op.value,
+                    path = op.path,
+                    from = op.from
+                };
 
                 allOps.Add(untypedOp);
             }
@@ -218,4 +229,15 @@ IList<Operation> IJsonPatchDocument.GetOperations()
 
         return allOps;
     }
+
+#if NET
+    /// <inheritdoc/>
+    static void IEndpointParameterMetadataProvider.PopulateMetadata(ParameterInfo parameter, EndpointBuilder builder)
+    {
+        ArgumentNullException.ThrowIfNull(parameter);
+        ArgumentNullException.ThrowIfNull(builder);
+
+        builder.Metadata.Add(new AcceptsMetadata(["application/json-patch+json"], parameter.ParameterType));
+    }
+#endif
 }
diff --git a/src/Features/JsonPatch/src/JsonPatchDocumentOfT.cs b/src/Features/JsonPatch/src/JsonPatchDocumentOfT.cs
index a5340ef515c4..afefe6b4a9d1 100644
--- a/src/Features/JsonPatch/src/JsonPatchDocumentOfT.cs
+++ b/src/Features/JsonPatch/src/JsonPatchDocumentOfT.cs
@@ -6,6 +6,7 @@
 using System.Globalization;
 using System.Linq;
 using System.Linq.Expressions;
+using System.Reflection;
 using Microsoft.AspNetCore.JsonPatch.Adapters;
 using Microsoft.AspNetCore.JsonPatch.Converters;
 using Microsoft.AspNetCore.JsonPatch.Exceptions;
@@ -15,6 +16,11 @@
 using Newtonsoft.Json;
 using Newtonsoft.Json.Serialization;
 
+#if NET
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Http.Metadata;
+#endif
+
 namespace Microsoft.AspNetCore.JsonPatch;
 
 // Implementation details: the purpose of this type of patch document is to ensure we can do type-checking
@@ -22,7 +28,11 @@ namespace Microsoft.AspNetCore.JsonPatch;
 // including type data in the JsonPatchDocument serialized as JSON (to allow for correct deserialization) - that's
 // not according to RFC 6902, and would thus break cross-platform compatibility.
 [JsonConverter(typeof(TypedJsonPatchDocumentConverter))]
+#if NET
+public class JsonPatchDocument<TModel> : IJsonPatchDocument, IEndpointParameterMetadataProvider where TModel : class
+#else
 public class JsonPatchDocument<TModel> : IJsonPatchDocument where TModel : class
+#endif
 {
     public List<Operation<TModel>> Operations { get; private set; }
 
@@ -31,7 +41,7 @@ public class JsonPatchDocument<TModel> : IJsonPatchDocument where TModel : class
 
     public JsonPatchDocument()
     {
-        Operations = new List<Operation<TModel>>();
+        Operations = [];
         ContractResolver = new DefaultContractResolver();
     }
 
@@ -656,11 +666,22 @@ IList<Operation> IJsonPatchDocument.GetOperations()
         return allOps;
     }
 
+#if NET
+    /// <inheritdoc/>
+    static void IEndpointParameterMetadataProvider.PopulateMetadata(ParameterInfo parameter, EndpointBuilder builder)
+    {
+        ArgumentNullException.ThrowIfNull(parameter);
+        ArgumentNullException.ThrowIfNull(builder);
+
+        builder.Metadata.Add(new AcceptsMetadata(["application/json-patch+json"], typeof(TModel)));
+    }
+#endif
+
     // Internal for testing
     internal string GetPath<TProp>(Expression<Func<TModel, TProp>> expr, string position)
     {
         var segments = GetPathSegments(expr.Body);
-        var path = String.Join("/", segments);
+        var path = string.Join("/", segments);
         if (position != null)
         {
             path += "/" + position;
@@ -712,8 +733,7 @@ private List<string> GetPathSegments(Expression expr)
 
     private string GetPropertyNameFromMemberExpression(MemberExpression memberExpression)
     {
-        var jsonObjectContract = ContractResolver.ResolveContract(memberExpression.Expression.Type) as JsonObjectContract;
-        if (jsonObjectContract != null)
+        if (ContractResolver.ResolveContract(memberExpression.Expression.Type) is JsonObjectContract jsonObjectContract)
         {
             return jsonObjectContract.Properties
                 .First(jsonProperty => jsonProperty.UnderlyingName == memberExpression.Member.Name)
diff --git a/src/Features/JsonPatch/src/Microsoft.AspNetCore.JsonPatch.csproj b/src/Features/JsonPatch/src/Microsoft.AspNetCore.JsonPatch.csproj
index f4027ea5fd71..65f81617bc6e 100644
--- a/src/Features/JsonPatch/src/Microsoft.AspNetCore.JsonPatch.csproj
+++ b/src/Features/JsonPatch/src/Microsoft.AspNetCore.JsonPatch.csproj
@@ -24,6 +24,7 @@
   <ItemGroup>
     <Reference Include="Microsoft.CSharp" Condition="'$(TargetFrameworkIdentifier)' != '.NETCoreApp'" />
     <Reference Include="Newtonsoft.Json" />
+    <Reference Include="Microsoft.AspNetCore.Http.Abstractions" Condition="'$(TargetFrameworkIdentifier)' == '.NETCoreApp'" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/src/OpenApi/sample/Endpoints/MapSchemasEndpoints.cs b/src/OpenApi/sample/Endpoints/MapSchemasEndpoints.cs
index ee1840d07164..5aea239062db 100644
--- a/src/OpenApi/sample/Endpoints/MapSchemasEndpoints.cs
+++ b/src/OpenApi/sample/Endpoints/MapSchemasEndpoints.cs
@@ -4,6 +4,7 @@
 using System.Collections.Immutable;
 using System.ComponentModel;
 using Microsoft.AspNetCore.Http.HttpResults;
+using Microsoft.AspNetCore.JsonPatch.SystemTextJson;
 
 public static class SchemasEndpointsExtensions
 {
@@ -36,6 +37,7 @@ public static IEndpointRouteBuilder MapSchemasEndpoints(this IEndpointRouteBuild
         schemas.MapPost("/location", (LocationContainer location) => { });
         schemas.MapPost("/parent", (ParentObject parent) => Results.Ok(parent));
         schemas.MapPost("/child", (ChildObject child) => Results.Ok(child));
+        schemas.MapPatch("/json-patch", (JsonPatchDocument<ParentObject> patchDoc) => Results.NoContent());
 
         return endpointRouteBuilder;
     }
diff --git a/src/OpenApi/sample/Sample.csproj b/src/OpenApi/sample/Sample.csproj
index bc97ebe3f173..cb2dc20c05a5 100644
--- a/src/OpenApi/sample/Sample.csproj
+++ b/src/OpenApi/sample/Sample.csproj
@@ -16,12 +16,13 @@
     <Reference Include="Microsoft.AspNetCore" />
     <Reference Include="Microsoft.AspNetCore.Authentication.JwtBearer" />
     <Reference Include="Microsoft.AspNetCore.Hosting" />
-    <Reference Include="Microsoft.AspNetCore.OpenApi" />
     <Reference Include="Microsoft.AspNetCore.Http" />
     <Reference Include="Microsoft.AspNetCore.Http.Results" />
+    <Reference Include="Microsoft.AspNetCore.JsonPatch.SystemTextJson" />
+    <Reference Include="Microsoft.AspNetCore.Mvc" />
+    <Reference Include="Microsoft.AspNetCore.OpenApi" />
     <Reference Include="Microsoft.AspNetCore.StaticFiles" />
     <Reference Include="Microsoft.Extensions.FileProviders.Embedded" />
-    <Reference Include="Microsoft.AspNetCore.Mvc" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_0/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt b/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_0/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt
index 788ea787fa14..0eecf7e47ee5 100644
--- a/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_0/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt
+++ b/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_0/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt
@@ -507,6 +507,28 @@
           }
         }
       }
+    },
+    "/schemas-by-ref/json-patch": {
+      "patch": {
+        "tags": [
+          "Sample"
+        ],
+        "requestBody": {
+          "content": {
+            "application/json-patch+json": {
+              "schema": {
+                "$ref": "#/components/schemas/JsonPatchDocumentOfParentObject"
+              }
+            }
+          },
+          "required": true
+        },
+        "responses": {
+          "200": {
+            "description": "OK"
+          }
+        }
+      }
     }
   },
   "components": {
@@ -599,6 +621,7 @@
           }
         }
       },
+      "JsonPatchDocumentOfParentObject": { },
       "LocationContainer": {
         "required": [
           "location"
diff --git a/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_1/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt b/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_1/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt
index 326da7fb0fb7..166b57e6aaab 100644
--- a/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_1/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt
+++ b/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Integration/snapshots/OpenApi3_1/OpenApiDocumentIntegrationTests.VerifyOpenApiDocument_documentName=schemas-by-ref.verified.txt
@@ -507,6 +507,28 @@
           }
         }
       }
+    },
+    "/schemas-by-ref/json-patch": {
+      "patch": {
+        "tags": [
+          "Sample"
+        ],
+        "requestBody": {
+          "content": {
+            "application/json-patch+json": {
+              "schema": {
+                "$ref": "#/components/schemas/JsonPatchDocumentOfParentObject"
+              }
+            }
+          },
+          "required": true
+        },
+        "responses": {
+          "200": {
+            "description": "OK"
+          }
+        }
+      }
     }
   },
   "components": {
@@ -599,6 +621,7 @@
           }
         }
       },
+      "JsonPatchDocumentOfParentObject": { },
       "LocationContainer": {
         "required": [
           "location"