Add root property jsonSchemaDialect

src/Microsoft.OpenApi.Readers/ParsingContext.cs

@@ -69,7 +69,7 @@ internal OpenApiDocument Parse(YamlDocument yamlDocument)
                 case string version when version.is3_0() || version.is3_1():
                     VersionService = new OpenApiV3VersionService(Diagnostic);
                     doc = VersionService.LoadDocument(RootNode);
-                    this.Diagnostic.SpecificationVersion = OpenApiSpecVersion.OpenApi3_0;
+                    this.Diagnostic.SpecificationVersion = version.is3_1() ? OpenApiSpecVersion.OpenApi3_1 : OpenApiSpecVersion.OpenApi3_0;
                     ValidateRequiredFields(doc, version);
                     break;
 

src/Microsoft.OpenApi.Readers/V3/OpenApiDocumentDeserializer.cs

@@ -21,6 +21,7 @@ internal static partial class OpenApiV3Deserializer
                 } /* Version is valid field but we already parsed it */
             },
             {"info", (o, n) => o.Info = LoadInfo(n)},
+            {"jsonSchemaDialect", (o, n) => o.JsonSchemaDialect = n.GetScalarValue() },
             {"servers", (o, n) => o.Servers = n.CreateList(LoadServer)},
             {"paths", (o, n) => o.Paths = LoadPaths(n)},
             {"webhooks", (o, n) => o.Webhooks = LoadPaths(n)},

src/Microsoft.OpenApi/Extensions/OpenApiSerializableExtensions.cs

@@ -117,6 +117,10 @@ public static void Serialize<T>(this T element, IOpenApiWriter writer, OpenApiSp
 
             switch (specVersion)
             {
+                case OpenApiSpecVersion.OpenApi3_1:
+                    element.SerializeAsV3(writer, OpenApiSpecVersion.OpenApi3_1);
+                    break;
+
                 case OpenApiSpecVersion.OpenApi3_0:
                     element.SerializeAsV3(writer);
                     break;

src/Microsoft.OpenApi/Interfaces/IOpenApiSerializable.cs

@@ -14,7 +14,8 @@ public interface IOpenApiSerializable : IOpenApiElement
         /// Serialize Open API element to v3.0.
         /// </summary>
         /// <param name="writer">The writer.</param>
-        void SerializeAsV3(IOpenApiWriter writer);
+        /// <param name="specVersion">The OpenApi specification version.</param>
+        void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion specVersion = OpenApiSpecVersion.OpenApi3_0);
 
         /// <summary>
         /// Serialize Open API element to v2.0.

src/Microsoft.OpenApi/Models/OpenApiCallback.cs

@@ -79,7 +79,7 @@ public void AddPathItem(RuntimeExpression expression, OpenApiPathItem pathItem)
         /// <summary>
         /// Serialize <see cref="OpenApiCallback"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {

src/Microsoft.OpenApi/Models/OpenApiComponents.cs

@@ -97,7 +97,7 @@ public OpenApiComponents(OpenApiComponents components)
         /// <summary>
         /// Serialize <see cref="OpenApiComponents"/> to Open Api v3.0.
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -293,8 +293,10 @@ public void SerializeAsV3(IOpenApiWriter writer)
                     }
                 });
 
-            // pathItems
-            writer.WriteOptionalMap(
+            // pathItems - only present in v3.1
+            if(version == OpenApiSpecVersion.OpenApi3_1)
+            {
+                writer.WriteOptionalMap(
                 OpenApiConstants.PathItems,
                 PathItems,
                 (w, key, component) =>
@@ -310,9 +312,10 @@ public void SerializeAsV3(IOpenApiWriter writer)
                         component.SerializeAsV3(w);
                     }
                 });
-
+            }
+
             // extensions
-            writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_0);
+            writer.WriteExtensions(Extensions, version);
 
             writer.WriteEndObject();
         }

src/Microsoft.OpenApi/Models/OpenApiConstants.cs

@@ -19,6 +19,11 @@ public static class OpenApiConstants
         /// Field: Info
         /// </summary>
         public const string Info = "info";
+
+        /// <summary>
+        /// Field: JsonSchemaDialect
+        /// </summary>
+        public const string JsonSchemaDialect = "jsonSchemaDialect";
 
         /// <summary>
         /// Field: Webhooks

src/Microsoft.OpenApi/Models/OpenApiContact.cs

@@ -54,11 +54,11 @@ public OpenApiContact(OpenApiContact contact)
         /// <summary>
         /// Serialize <see cref="OpenApiContact"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
-            WriteInternal(writer, OpenApiSpecVersion.OpenApi3_0);
+            WriteInternal(writer, version);
         }
-
+        
         /// <summary>
         /// Serialize <see cref="OpenApiContact"/> to Open Api v2.0
         /// </summary>

src/Microsoft.OpenApi/Models/OpenApiDiscriminator.cs

@@ -39,7 +39,7 @@ public OpenApiDiscriminator(OpenApiDiscriminator discriminator)
         /// <summary>
         /// Serialize <see cref="OpenApiDiscriminator"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {

src/Microsoft.OpenApi/Models/OpenApiDocument.cs

@@ -29,6 +29,11 @@ public class OpenApiDocument : IOpenApiSerializable, IOpenApiExtensible
         /// </summary>
         public OpenApiInfo Info { get; set; }
 
+        /// <summary>
+        /// The default value for the $schema keyword within Schema Objects contained within this OAS document. This MUST be in the form of a URI.
+        /// </summary>
+        public string JsonSchemaDialect { get; set; }
+
         /// <summary>
         /// An array of Server Objects, which provide connectivity information to a target server.
         /// </summary>
@@ -89,6 +94,7 @@ public OpenApiDocument(OpenApiDocument document)
         {
             Workspace = document?.Workspace != null ? new(document?.Workspace) : null;
             Info = document?.Info != null ? new(document?.Info) : null;
+            JsonSchemaDialect = document?.JsonSchemaDialect ?? JsonSchemaDialect;
             Servers = document?.Servers != null ? new List<OpenApiServer>(document.Servers) : null;
             Paths = document?.Paths != null ? new(document?.Paths) : null;
             Webhooks = document?.Webhooks != null ? new Dictionary<string, OpenApiPathItem>(document.Webhooks) : null;
@@ -102,7 +108,7 @@ public OpenApiDocument(OpenApiDocument document)
         /// <summary>
         /// Serialize <see cref="OpenApiDocument"/> to the latest patch of OpenAPI object V3.0.
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -112,19 +118,36 @@ public void SerializeAsV3(IOpenApiWriter writer)
             writer.WriteStartObject();
 
             // openapi
-            writer.WriteProperty(OpenApiConstants.OpenApi, "3.0.1");
-
+            switch (version)
+            {
+                case OpenApiSpecVersion.OpenApi3_1:
+                    writer.WriteProperty(OpenApiConstants.OpenApi, "3.1.0");
+                    break;
+                case OpenApiSpecVersion.OpenApi3_0:
+                    writer.WriteProperty(OpenApiConstants.OpenApi, "3.0.1");
+                    break;
+                default:
+                    writer.WriteProperty(OpenApiConstants.OpenApi, "3.0.1");
+                    break;
+            }
+
             // info
             writer.WriteRequiredObject(OpenApiConstants.Info, Info, (w, i) => i.SerializeAsV3(w));
 
+            // jsonSchemaDialect
+            if(version == OpenApiSpecVersion.OpenApi3_1)
+                writer.WriteProperty(OpenApiConstants.JsonSchemaDialect, JsonSchemaDialect);
+
             // servers
             writer.WriteOptionalCollection(OpenApiConstants.Servers, Servers, (w, s) => s.SerializeAsV3(w));
 
             // paths
             writer.WriteRequiredObject(OpenApiConstants.Paths, Paths, (w, p) => p.SerializeAsV3(w));
 
             // webhooks
-            writer.WriteOptionalMap(
+            if (version == OpenApiSpecVersion.OpenApi3_1)
+            {
+                writer.WriteOptionalMap(
                 OpenApiConstants.Webhooks,
                 Webhooks,
                 (w, key, component) =>
@@ -140,6 +163,7 @@ public void SerializeAsV3(IOpenApiWriter writer)
                         component.SerializeAsV3(w);
                     }
                 });
+            }                
 
             // components
             writer.WriteOptionalObject(OpenApiConstants.Components, Components, (w, c) => c.SerializeAsV3(w));
@@ -157,7 +181,7 @@ public void SerializeAsV3(IOpenApiWriter writer)
             writer.WriteOptionalObject(OpenApiConstants.ExternalDocs, ExternalDocs, (w, e) => e.SerializeAsV3(w));
 
             // extensions
-            writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_0);
+            writer.WriteExtensions(Extensions, version);
 
             writer.WriteEndObject();
         }

src/Microsoft.OpenApi/Models/OpenApiEncoding.cs

@@ -74,7 +74,7 @@ public OpenApiEncoding(OpenApiEncoding encoding)
         /// <summary>
         /// Serialize <see cref="OpenApiExternalDocs"/> to Open Api v3.0.
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -99,7 +99,7 @@ public void SerializeAsV3(IOpenApiWriter writer)
             writer.WriteProperty(OpenApiConstants.AllowReserved, AllowReserved, false);
 
             // extensions
-            writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_0);
+            writer.WriteExtensions(Extensions, version);
 
             writer.WriteEndObject();
         }

src/Microsoft.OpenApi/Models/OpenApiExample.cs

@@ -76,7 +76,7 @@ public OpenApiExample(OpenApiExample example)
         /// <summary>
         /// Serialize <see cref="OpenApiExample"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {

src/Microsoft.OpenApi/Models/OpenApiExtensibleDictionary.cs

@@ -41,7 +41,7 @@ protected OpenApiExtensibleDictionary(
         /// <summary>
         /// Serialize to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -55,7 +55,7 @@ public void SerializeAsV3(IOpenApiWriter writer)
                 writer.WriteRequiredObject(item.Key, item.Value, (w, p) => p.SerializeAsV3(w));
             }
 
-            writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_0);
+            writer.WriteExtensions(Extensions, version);
 
             writer.WriteEndObject();
         }

src/Microsoft.OpenApi/Models/OpenApiExternalDocs.cs

@@ -47,11 +47,11 @@ public OpenApiExternalDocs(OpenApiExternalDocs externalDocs)
         /// <summary>
         /// Serialize <see cref="OpenApiExternalDocs"/> to Open Api v3.0.
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
-            WriteInternal(writer, OpenApiSpecVersion.OpenApi3_0);
+            WriteInternal(writer, version);
         }
-
+        
         /// <summary>
         /// Serialize <see cref="OpenApiExternalDocs"/> to Open Api v2.0.
         /// </summary>

src/Microsoft.OpenApi/Models/OpenApiHeader.cs

@@ -115,7 +115,7 @@ public OpenApiHeader(OpenApiHeader header)
         /// <summary>
         /// Serialize <see cref="OpenApiHeader"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {

src/Microsoft.OpenApi/Models/OpenApiInfo.cs

@@ -76,7 +76,7 @@ public OpenApiInfo(OpenApiInfo info)
         /// <summary>
         /// Serialize <see cref="OpenApiInfo"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -88,9 +88,12 @@ public void SerializeAsV3(IOpenApiWriter writer)
             // title
             writer.WriteProperty(OpenApiConstants.Title, Title);
 
-            // summary
-            writer.WriteProperty(OpenApiConstants.Summary, Summary);
-
+            // summary - present in 3.1
+            if (version == OpenApiSpecVersion.OpenApi3_1)
+            {
+                writer.WriteProperty(OpenApiConstants.Summary, Summary);
+            }
+
             // description
             writer.WriteProperty(OpenApiConstants.Description, Description);
 

src/Microsoft.OpenApi/Models/OpenApiLicense.cs

@@ -53,9 +53,9 @@ public OpenApiLicense(OpenApiLicense license)
         /// <summary>
         /// Serialize <see cref="OpenApiLicense"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
-            WriteInternal(writer, OpenApiSpecVersion.OpenApi3_0);
+            WriteInternal(writer, version);
         }
 
         /// <summary>
@@ -78,8 +78,11 @@ private void WriteInternal(IOpenApiWriter writer, OpenApiSpecVersion specVersion
             // name
             writer.WriteProperty(OpenApiConstants.Name, Name);
 
-            // identifier
-            writer.WriteProperty(OpenApiConstants.Identifier, Identifier);
+            // identifier - present in v3.1
+            if (specVersion == OpenApiSpecVersion.OpenApi3_1)
+            {
+                writer.WriteProperty(OpenApiConstants.Identifier, Identifier);
+            }
 
             // url
             writer.WriteProperty(OpenApiConstants.Url, Url?.OriginalString);

src/Microsoft.OpenApi/Models/OpenApiLink.cs

@@ -85,7 +85,7 @@ public OpenApiLink(OpenApiLink link)
         /// <summary>
         /// Serialize <see cref="OpenApiLink"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {

src/Microsoft.OpenApi/Models/OpenApiMediaType.cs

@@ -63,7 +63,7 @@ public OpenApiMediaType(OpenApiMediaType mediaType)
         /// <summary>
         /// Serialize <see cref="OpenApiMediaType"/> to Open Api v3.0.
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -85,7 +85,7 @@ public void SerializeAsV3(IOpenApiWriter writer)
             writer.WriteOptionalMap(OpenApiConstants.Encoding, Encoding, (w, e) => e.SerializeAsV3(w));
 
             // extensions
-            writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_0);
+            writer.WriteExtensions(Extensions, version);
 
             writer.WriteEndObject();
         }

src/Microsoft.OpenApi/Models/OpenApiOAuthFlow.cs

@@ -61,7 +61,7 @@ public OpenApiOAuthFlow(OpenApiOAuthFlow oAuthFlow)
         /// <summary>
         /// Serialize <see cref="OpenApiOAuthFlow"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -83,7 +83,7 @@ public void SerializeAsV3(IOpenApiWriter writer)
             writer.WriteRequiredMap(OpenApiConstants.Scopes, Scopes, (w, s) => w.WriteValue(s));
 
             // extensions
-            writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_0);
+            writer.WriteExtensions(Extensions, version);
 
             writer.WriteEndObject();
         }

src/Microsoft.OpenApi/Models/OpenApiOAuthFlows.cs

@@ -59,7 +59,7 @@ public OpenApiOAuthFlows(OpenApiOAuthFlows oAuthFlows)
         /// <summary>
         /// Serialize <see cref="OpenApiOAuthFlows"/> to Open Api v3.0
         /// </summary>
-        public void SerializeAsV3(IOpenApiWriter writer)
+        public void SerializeAsV3(IOpenApiWriter writer, OpenApiSpecVersion version = OpenApiSpecVersion.OpenApi3_0)
         {
             if (writer == null)
             {
@@ -87,7 +87,7 @@ public void SerializeAsV3(IOpenApiWriter writer)
                 (w, o) => o.SerializeAsV3(w));
 
             // extensions
-            writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_0);
+            writer.WriteExtensions(Extensions, version);
 
             writer.WriteEndObject();
         }