Support .NET 10

- Add support for ASP.NET Core 10 and Microsoft.OpenApi v2.
- Add opt-in support for OpenAPI 3.1 when targeting `net10.0`.
- Mark `SerializeAsV2` as obsolete.
- Remove `--serializeasv2` switch (maybe can add it back as an obsolete option that means `--openapiversion 2.0`).

Author: martincostello

.github/workflows/build.yml

@@ -53,6 +53,7 @@ jobs:
         dotnet-version: |
           6.0.x
           8.0.x
+          9.0.x
 
     - name: Setup .NET SDK
       uses: actions/setup-dotnet@3951f0dfe7a07e2313ec93c75700083e2005cbab # v4.3.0

Directory.Build.props

@@ -24,6 +24,8 @@
     TODO Fix warning from Swashbuckle.AspNetCore with dotnet pack
     -->
     <NoWarn>$(NoWarn);NU5128</NoWarn>
+    <!-- TODO Remove once .NET 10 is stable -->
+    <NoWarn>$(NoWarn);NU5104</NoWarn>
     <NuGetAuditMode>direct</NuGetAuditMode>
     <!--
     TODO Go through the code and add nullable annotations

Directory.Packages.props

@@ -34,4 +34,9 @@
     <PackageVersion Include="xunit.core" Version="2.9.2" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="2.8.2" />
   </ItemGroup>
+  <ItemGroup Condition="$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net10.0'))">
+    <PackageVersion Update="Microsoft.AspNetCore.OpenApi" Version="10.0.0-preview.1.25120.3" />
+    <PackageVersion Update="Microsoft.OpenApi" Version="2.0.0-preview5" />
+    <PackageVersion Update="Microsoft.OpenApi.Readers" Version="2.0.0-preview5" />
+  </ItemGroup>
 </Project>

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "9.0.200",
+    "version": "10.0.100-preview.1.25120.13",
     "allowPrerelease": false,
     "rollForward": "latestMajor"
   }

perf/Swashbuckle.AspNetCore.Benchmarks/Swashbuckle.AspNetCore.Benchmarks.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <IsPackable>false</IsPackable>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFrameworks>net10.0;net8.0</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="..\..\src\Shared\JsonSchemaTypes.cs" Link="JsonSchemaTypes.cs" />

src/Shared/JsonExtensions.cs

@@ -0,0 +1,18 @@
+#if NET10_0_OR_GREATER
+using System.Text.Json;
+using System.Text.Json.Nodes;
+
+namespace Swashbuckle.AspNetCore;
+
+internal static class JsonExtensions
+{
+    private static readonly JsonSerializerOptions Options = new()
+    {
+        NewLine = "\n",
+        WriteIndented = true,
+    };
+
+    public static string ToJson(this JsonNode value)
+        => value.ToJsonString(Options);
+}
+#endif

src/Shared/JsonSchemaTypes.cs

@@ -1,12 +1,26 @@
+#if NET10_0_OR_GREATER
+using Microsoft.OpenApi.Models;
+#endif
+
 namespace Swashbuckle.AspNetCore;
 
 internal static class JsonSchemaTypes
 {
+#if NET10_0_OR_GREATER
+    public static readonly JsonSchemaType Array = JsonSchemaType.Array;
+    public static readonly JsonSchemaType Boolean = JsonSchemaType.Boolean;
+    public static readonly JsonSchemaType Integer = JsonSchemaType.Integer;
+    public static readonly JsonSchemaType Number = JsonSchemaType.Number;
+    public static readonly JsonSchemaType Null = JsonSchemaType.Null;
+    public static readonly JsonSchemaType Object = JsonSchemaType.Object;
+    public static readonly JsonSchemaType String = JsonSchemaType.String;
+#else
     public const string Array = "array";
     public const string Boolean = "boolean";
     public const string Integer = "integer";
     public const string Number = "number";
     public const string Null = "null";
     public const string Object = "object";
     public const string String = "string";
+#endif
 }

src/Swashbuckle.AspNetCore.Annotations/AnnotationsOperationFilter.cs

@@ -63,10 +63,13 @@ private static void ApplySwaggerOperationAttribute(
             if (swaggerOperationAttribute.OperationId != null)
                 operation.OperationId = swaggerOperationAttribute.OperationId;
 
+            // TODO Fix this
+#if !NET10_0_OR_GREATER
             if (swaggerOperationAttribute.Tags != null)
             {
                 operation.Tags = [.. swaggerOperationAttribute.Tags.Select(tagName => new OpenApiTag { Name = tagName })];
             }
+#endif
         }
 
         public static void ApplySwaggerOperationFilterAttributes(

src/Swashbuckle.AspNetCore.Annotations/SwaggerResponseAttribute.cs

@@ -22,10 +22,12 @@ public SwaggerResponseAttribute(int statusCode, string description = null, Type
             ContentTypes = contentTypes;
         }
 
+#if !NET10_0_OR_GREATER
         /// <summary>
         /// A short description of the response. GFM syntax can be used for rich text representation.
         /// </summary>
         public string Description { get; set; }
+#endif
 
         /// <summary>
         /// A collection of MIME types that the response can be produced with.

src/Swashbuckle.AspNetCore.Annotations/Swashbuckle.AspNetCore.Annotations.csproj

@@ -8,7 +8,7 @@
     <NoWarn>$(NoWarn);1591</NoWarn>
     <PackageTags>swagger;documentation;discovery;help;webapi;aspnet;aspnetcore;annotations</PackageTags>
     <SignAssembly>true</SignAssembly>
-    <TargetFrameworks>net9.0;net8.0;net6.0;netstandard2.0</TargetFrameworks>
+    <TargetFrameworks>net10.0;net9.0;net8.0;net6.0;netstandard2.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>