Resolve PR comments

Author: Michael-Wamae

src/Microsoft.OpenApi/Models/OpenApiDiscriminator.cs

@@ -1,7 +1,6 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
-using System;
 using System.Collections.Generic;
 using Microsoft.OpenApi.Interfaces;
 using Microsoft.OpenApi.Models.References;
@@ -50,8 +49,7 @@ public OpenApiDiscriminator(OpenApiDiscriminator discriminator)
         /// <param name="writer"></param>
         public void SerializeAsV31(IOpenApiWriter writer)
         {
-            SerializeInternal(writer,
-               (writer, referenceElement) => referenceElement.SerializeAsV31(writer));
+            SerializeInternal(writer);
 
             // extensions
             writer.WriteExtensions(Extensions, OpenApiSpecVersion.OpenApi3_1);
@@ -64,16 +62,16 @@ public void SerializeAsV31(IOpenApiWriter writer)
         /// </summary>
         public void SerializeAsV3(IOpenApiWriter writer)
         {
-            SerializeInternal(writer,
-                (writer, referenceElement) => referenceElement.SerializeAsV3(writer));
+            SerializeInternal(writer);
 
             writer.WriteEndObject();
         }
 
         /// <summary>
         /// Serialize <see cref="OpenApiDiscriminator"/> to Open Api v3.0
         /// </summary>
-        private void SerializeInternal(IOpenApiWriter writer, Action<IOpenApiWriter, IOpenApiReferenceHolder> action)
+        /// <param name="writer"></param>
+        private void SerializeInternal(IOpenApiWriter writer)
         {
             Utils.CheckArgumentNull(writer);
 
@@ -83,7 +81,13 @@ private void SerializeInternal(IOpenApiWriter writer, Action<IOpenApiWriter, IOp
             writer.WriteProperty(OpenApiConstants.PropertyName, PropertyName);
 
             // mapping
-            writer.WriteOptionalMap(OpenApiConstants.Mapping, Mapping, (w, key, reference) => action(w, reference));
+            writer.WriteOptionalMap(OpenApiConstants.Mapping, Mapping, (w, s) =>
+            {
+                if (!string.IsNullOrEmpty(s.Reference.ReferenceV3) && s.Reference.ReferenceV3 is not null)
+                {
+                    w.WriteValue(s.Reference.ReferenceV3);
+                }
+            });
         }
 
         /// <summary>

src/Microsoft.OpenApi/Reader/V3/OpenApiDiscriminatorDeserializer.cs

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
-using System.Collections.Generic;
+using System;
 using System.Linq;
 using Microsoft.OpenApi.Models;
 using Microsoft.OpenApi.Models.References;
@@ -24,7 +24,7 @@ internal static partial class OpenApiV3Deserializer
                 },
                 {
                     "mapping",
-                    (o, n, doc) => o.Mapping = n.CreateMap(LoadMapping, doc)
+                    (o, n, doc) => o.Mapping = n.CreateSimpleMap((node) => LoadMapping(node, doc))
                 }
             };
 
@@ -44,10 +44,8 @@ public static OpenApiDiscriminator LoadDiscriminator(ParseNode node, OpenApiDocu
         }
         public static OpenApiSchemaReference LoadMapping(ParseNode node, OpenApiDocument hostDocument)
         {
-            var mapNode = node.CheckMapNode("mapping");
-
-            var pointer = mapNode.GetReferencePointer();
-            var reference = GetReferenceIdAndExternalResource(pointer!);
+            var pointer = node.GetScalarValue() ?? throw new InvalidOperationException("Could not get a pointer reference");
+            var reference = GetReferenceIdAndExternalResource(pointer);
             return new OpenApiSchemaReference(reference.Item1, hostDocument, reference.Item2);
         }
     }

src/Microsoft.OpenApi/Reader/V3/OpenApiV3VersionService.cs

@@ -5,12 +5,9 @@
 using System.Collections.Generic;
 using System.Linq;
 using Microsoft.OpenApi.Any;
-using Microsoft.OpenApi.Exceptions;
-using Microsoft.OpenApi.Extensions;
 using Microsoft.OpenApi.Interfaces;
 using Microsoft.OpenApi.Models;
 using Microsoft.OpenApi.Models.References;
-using Microsoft.OpenApi.Properties;
 using Microsoft.OpenApi.Reader.ParseNodes;
 
 namespace Microsoft.OpenApi.Reader.V3

src/Microsoft.OpenApi/Reader/V31/OpenApiDiscriminatorDeserializer.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using System.Linq;
 using Microsoft.OpenApi.Extensions;
 using Microsoft.OpenApi.Models;
@@ -26,7 +25,7 @@ internal static partial class OpenApiV31Deserializer
                 {
                     "mapping", (o, n, doc) =>
                     {
-                        o.Mapping = n.CreateMap(LoadMapping, doc);
+                        o.Mapping = n.CreateSimpleMap((node) => LoadMapping(node, doc));
                     }
                 }
             };
@@ -52,10 +51,8 @@ public static OpenApiDiscriminator LoadDiscriminator(ParseNode node, OpenApiDocu
 
         public static OpenApiSchemaReference LoadMapping(ParseNode node, OpenApiDocument hostDocument)
         {
-            var mapNode = node.CheckMapNode("mapping");
-
-            var pointer = mapNode.GetReferencePointer();
-            var reference = GetReferenceIdAndExternalResource(pointer!);
+            var pointer = node.GetScalarValue() ?? throw new InvalidOperationException("Could not get a pointer reference");
+            var reference = GetReferenceIdAndExternalResource(pointer);
             return new OpenApiSchemaReference(reference.Item1, hostDocument, reference.Item2);
         }
     }

src/Microsoft.OpenApi/Reader/V31/OpenApiV31VersionService.cs

@@ -5,12 +5,9 @@
 using System.Collections.Generic;
 using System.Linq;
 using Microsoft.OpenApi.Any;
-using Microsoft.OpenApi.Exceptions;
-using Microsoft.OpenApi.Extensions;
 using Microsoft.OpenApi.Interfaces;
 using Microsoft.OpenApi.Models;
 using Microsoft.OpenApi.Models.References;
-using Microsoft.OpenApi.Properties;
 using Microsoft.OpenApi.Reader.ParseNodes;
 using Microsoft.OpenApi.Reader.V3;
 

test/Microsoft.OpenApi.Readers.Tests/V31Tests/Samples/OpenApiDocument/docWithExample.yaml

@@ -75,10 +75,8 @@ components: # Reusable components for the API
       discriminator: # The discriminator for resolving the concrete schema type
         propertyName: petType
         mapping:
-          cat:
-            $ref: '#/components/schemas/Cat'
-          dog:
-            $ref: '#/components/schemas/Dog'
+          cat: '#/components/schemas/Cat'
+          dog: '#/components/schemas/Dog'
     Cat: # A schema for a cat object
       allOf:
         - $ref: '#/components/schemas/Pet'

test/Microsoft.OpenApi.Readers.Tests/V3Tests/OpenApiDiscriminatorTests.cs

@@ -2,14 +2,11 @@
 // Licensed under the MIT license.
 
 using System;
-using System.Diagnostics;
 using System.IO;
 using System.Threading.Tasks;
 using Microsoft.OpenApi.Models;
 using Microsoft.OpenApi.Models.References;
 using Microsoft.OpenApi.Reader;
-using Microsoft.VisualStudio.TestPlatform.Utilities;
-using Newtonsoft.Json;
 using Xunit;
 
 namespace Microsoft.OpenApi.Readers.Tests.V3Tests
@@ -41,7 +38,7 @@ public async Task ParseBasicDiscriminatorShouldSucceed()
                    Mapping =
                     {
                             ["puppy"] = new OpenApiSchemaReference("Dog", openApiDocument),
-                            ["kitten"] = new OpenApiSchemaReference("Cat", openApiDocument)
+                            ["monster"] = new OpenApiSchemaReference("schema.json" , openApiDocument, "https://gigantic-server.com/schemas/Monster/schema.json")
                     }
                }, discriminator);
         }

test/Microsoft.OpenApi.Readers.Tests/V3Tests/Samples/OpenApiDiscriminator/basicDiscriminator.yaml

@@ -1,6 +1,4 @@
 propertyName: pet_type
 mapping:
-    puppy: 
-      $ref: '#/components/schemas/Dog'
-    kitten: 
-      $ref: '#/components/schemas/Cat'
+    puppy: '#/components/schemas/Dog'
+    monster: https://gigantic-server.com/schemas/Monster/schema.json