fix: makes reference fields immutable

baywet · baywet · commit fda05d465ef8 · 2025-02-04T12:18:22.000-05:00
diff --git a/src/Microsoft.OpenApi/Models/OpenApiReference.cs b/src/Microsoft.OpenApi/Models/OpenApiReference.cs
@@ -4,14 +4,28 @@
 using System;
 using Microsoft.OpenApi.Extensions;
 using Microsoft.OpenApi.Interfaces;
+using Microsoft.OpenApi.Models.Interfaces;
 using Microsoft.OpenApi.Writers;
 
+#if !NET5_0_OR_GREATER
+namespace System.Runtime.CompilerServices {
+   using System.ComponentModel;
+   /// <summary>
+   /// Reserved to be used by the compiler for tracking metadata.
+   /// This class should not be used by developers in source code.
+   /// </summary>
+   [EditorBrowsable(EditorBrowsableState.Never)]
+   internal static class IsExternalInit {
+   }
+}
+#endif
+
 namespace Microsoft.OpenApi.Models
 {
     /// <summary>
     /// A simple object to allow referencing other components in the specification, internally and externally.
     /// </summary>
-    public class OpenApiReference : IOpenApiSerializable
+    public class OpenApiReference : IOpenApiSerializable, IOpenApiDescribedElement, IOpenApiSummarizedElement
     {
         /// <summary>
         /// A short summary which by default SHOULD override that of the referenced component.
@@ -32,13 +46,13 @@ public class OpenApiReference : IOpenApiSerializable
         /// 1. a absolute/relative file path, for example:  ../commons/pet.json
         /// 2. a Url, for example: http://localhost/pet.json
         /// </summary>
-        public string ExternalResource { get; set; }
+        public string ExternalResource { get; init; }
 
         /// <summary>
         /// The element type referenced.
         /// </summary>
         /// <remarks>This must be present if <see cref="ExternalResource"/> is not present.</remarks>
-        public ReferenceType? Type { get; set; }
+        public ReferenceType? Type { get; init; }
 
         /// <summary>
         /// The identifier of the reusable component of one particular ReferenceType.
@@ -47,7 +61,7 @@ public class OpenApiReference : IOpenApiSerializable
         /// If ExternalResource is not present, this is the name of the component without the reference type name.
         /// For example, if the reference is '#/components/schemas/componentName', the Id is 'componentName'.
         /// </summary>
-        public string Id { get; set; }
+        public string Id { get; init; }
 
         /// <summary>
         /// Gets a flag indicating whether this reference is an external reference.
@@ -62,12 +76,12 @@ public class OpenApiReference : IOpenApiSerializable
         /// <summary>
         /// Gets a flag indicating whether a file is a valid OpenAPI document or a fragment
         /// </summary>
-        public bool IsFragment = false;
+        public bool IsFragment { get; init; }
 
         /// <summary>
         /// The OpenApiDocument that is hosting the OpenApiReference instance. This is used to enable dereferencing the reference.
         /// </summary>
-        public OpenApiDocument HostDocument { get; set; }
+        public OpenApiDocument HostDocument { get; init; }
 
         /// <summary>
         /// Gets the full reference string for v3.0.
@@ -145,12 +159,13 @@ public OpenApiReference() { }
         /// </summary>
         public OpenApiReference(OpenApiReference reference)
         {
-            Summary = reference?.Summary;
-            Description = reference?.Description;
-            ExternalResource = reference?.ExternalResource;
-            Type = reference?.Type;
-            Id = reference?.Id;
-            HostDocument = reference?.HostDocument;
+            Utils.CheckArgumentNull(reference);
+            Summary = reference.Summary;
+            Description = reference.Description;
+            ExternalResource = reference.ExternalResource;
+            Type = reference.Type;
+            Id = reference.Id;
+            HostDocument = reference.HostDocument;
         }
 
         /// <summary>
diff --git a/src/Microsoft.OpenApi/Reader/V3/OpenApiV3VersionService.cs b/src/Microsoft.OpenApi/Reader/V3/OpenApiV3VersionService.cs
@@ -116,7 +116,7 @@ public OpenApiReference ConvertToOpenApiReference(
                     }
                     // Where fragments point into a non-OpenAPI document, the id will be the complete fragment identifier
                     var id = segments[1];
-                    var openApiReference = new OpenApiReference();
+                    var isFragment = false;
 
                     // $ref: externalSource.yaml#/Pet
                     if (id.StartsWith("/components/", StringComparison.Ordinal))
@@ -152,12 +152,16 @@ public OpenApiReference ConvertToOpenApiReference(
                     }
                     else
                     {
-                        openApiReference.IsFragment = true;
+                        isFragment = true;
                     }
 
-                    openApiReference.ExternalResource = segments[0];
-                    openApiReference.Type = type;
-                    openApiReference.Id = id;
+                    var openApiReference = new OpenApiReference
+                    {
+                        ExternalResource = segments[0],
+                        Type = type,
+                        Id = id,
+                        IsFragment = isFragment,
+                    };
 
                     return openApiReference;
                 }
diff --git a/src/Microsoft.OpenApi/Services/ReferenceHostDocumentSetter.cs b/src/Microsoft.OpenApi/Services/ReferenceHostDocumentSetter.cs
@@ -23,7 +23,10 @@ public override void Visit(IOpenApiReferenceHolder referenceHolder)
         {
             if (referenceHolder.Reference != null)
             {
-                referenceHolder.Reference.HostDocument = _currentDocument;
+                referenceHolder.Reference = new OpenApiReference(referenceHolder.Reference)
+                {
+                    HostDocument = _currentDocument,
+                };
             }
         }
     }
diff --git a/test/Microsoft.OpenApi.Readers.Tests/ReferenceService/TryLoadReferenceV2Tests.cs b/test/Microsoft.OpenApi.Readers.Tests/ReferenceService/TryLoadReferenceV2Tests.cs
@@ -118,7 +118,11 @@ public async Task LoadResponseAndSchemaReference()
                     }
                 };
 
-            ((OpenApiSchemaReference)expected.Content["application/json"].Schema).Reference.HostDocument = result.Document;
+            var schemaReference = (OpenApiSchemaReference)expected.Content["application/json"].Schema;
+            schemaReference.Reference = new OpenApiReference(schemaReference.Reference)
+            {
+                HostDocument = result.Document,
+            };
             var actual = reference.Target;
 
             // Assert
diff --git a/test/Microsoft.OpenApi.Readers.Tests/V3Tests/OpenApiDocumentTests.cs b/test/Microsoft.OpenApi.Readers.Tests/V3Tests/OpenApiDocumentTests.cs
@@ -1046,11 +1046,11 @@ public async Task ParseModifiedPetStoreDocumentWithTagAndSecurityShouldSucceed()
                     }
             };
 
-            tagReference1.Reference.HostDocument = expected;
-            tagReference2.Reference.HostDocument = expected;
-            petSchemaReference.Reference.HostDocument = expected;
-            newPetSchemaReference.Reference.HostDocument = expected;
-            errorModelSchemaReference.Reference.HostDocument = expected;
+            tagReference1.Reference = new OpenApiReference(tagReference1.Reference) {HostDocument = expected };
+            tagReference2.Reference = new OpenApiReference(tagReference2.Reference) {HostDocument = expected };
+            petSchemaReference.Reference = new OpenApiReference(petSchemaReference.Reference) {HostDocument = expected };
+            newPetSchemaReference.Reference = new OpenApiReference(newPetSchemaReference.Reference) {HostDocument = expected };
+            errorModelSchemaReference.Reference = new OpenApiReference(errorModelSchemaReference.Reference) {HostDocument = expected };
 
             actual.Document.Should().BeEquivalentTo(expected, options => options
             .IgnoringCyclicReferences()
@@ -1284,7 +1284,7 @@ public async Task ParseDocWithRefsUsingProxyReferencesSucceeds()
             var outputDoc = (await doc.SerializeAsYamlAsync(OpenApiSpecVersion.OpenApi3_0)).MakeLineBreaksEnvironmentNeutral();
             var expectedParam = expected.Paths["/pets"].Operations[OperationType.Get].Parameters[0];
             var expectedParamReference = Assert.IsType<OpenApiParameterReference>(expectedParam);
-            expectedParamReference.Reference.HostDocument = doc;
+            expectedParamReference.Reference = new OpenApiReference(expectedParamReference.Reference) {HostDocument = doc};
 
             var actualParamReference = Assert.IsType<OpenApiParameterReference>(actualParam);
 
diff --git a/test/Microsoft.OpenApi.Tests/PublicApi/PublicApi.approved.txt b/test/Microsoft.OpenApi.Tests/PublicApi/PublicApi.approved.txt
@@ -957,21 +957,21 @@ namespace Microsoft.OpenApi.Models
         public OpenApiPaths() { }
         public OpenApiPaths(Microsoft.OpenApi.Models.OpenApiPaths paths) { }
     }
-    public class OpenApiReference : Microsoft.OpenApi.Interfaces.IOpenApiElement, Microsoft.OpenApi.Interfaces.IOpenApiSerializable
+    public class OpenApiReference : Microsoft.OpenApi.Interfaces.IOpenApiElement, Microsoft.OpenApi.Interfaces.IOpenApiSerializable, Microsoft.OpenApi.Models.Interfaces.IOpenApiDescribedElement, Microsoft.OpenApi.Models.Interfaces.IOpenApiSummarizedElement
     {
-        public bool IsFragment;
         public OpenApiReference() { }
         public OpenApiReference(Microsoft.OpenApi.Models.OpenApiReference reference) { }
         public string Description { get; set; }
-        public string ExternalResource { get; set; }
-        public Microsoft.OpenApi.Models.OpenApiDocument HostDocument { get; set; }
-        public string Id { get; set; }
         public bool IsExternal { get; }
         public bool IsLocal { get; }
         public string ReferenceV2 { get; }
         public string ReferenceV3 { get; }
         public string Summary { get; set; }
-        public Microsoft.OpenApi.Models.ReferenceType? Type { get; set; }
+        public string ExternalResource { get; init; }
+        public Microsoft.OpenApi.Models.OpenApiDocument HostDocument { get; init; }
+        public string Id { get; init; }
+        public bool IsFragment { get; init; }
+        public Microsoft.OpenApi.Models.ReferenceType? Type { get; init; }
         public void SerializeAsV2(Microsoft.OpenApi.Writers.IOpenApiWriter writer) { }
         public void SerializeAsV3(Microsoft.OpenApi.Writers.IOpenApiWriter writer) { }
         public void SerializeAsV31(Microsoft.OpenApi.Writers.IOpenApiWriter writer) { }

Original file line number	Diff line number	Diff line change
`@@ -116,7 +116,7 @@ public OpenApiReference ConvertToOpenApiReference(`
`116`	`116`	`}`
`117`	`117`	`// Where fragments point into a non-OpenAPI document, the id will be the complete fragment identifier`
`118`	`118`	`var id = segments[1];`
`119`		`- var openApiReference = new OpenApiReference();`
	`119`	`+ var isFragment = false;`
`120`	`120`
`121`	`121`	`// $ref: externalSource.yaml#/Pet`
`122`	`122`	`if (id.StartsWith("/components/", StringComparison.Ordinal))`
`@@ -152,12 +152,16 @@ public OpenApiReference ConvertToOpenApiReference(`
`152`	`152`	`}`
`153`	`153`	`else`
`154`	`154`	`{`
`155`		`- openApiReference.IsFragment = true;`
	`155`	`+ isFragment = true;`
`156`	`156`	`}`
`157`	`157`
`158`		`- openApiReference.ExternalResource = segments[0];`
`159`		`- openApiReference.Type = type;`
`160`		`- openApiReference.Id = id;`
	`158`	`+ var openApiReference = new OpenApiReference`
	`159`	`+ {`
	`160`	`+ ExternalResource = segments[0],`
	`161`	`+ Type = type,`
	`162`	`+ Id = id,`
	`163`	`+ IsFragment = isFragment,`
	`164`	`+ };`
`161`	`165`
`162`	`166`	`return openApiReference;`
`163`	`167`	`}`
Original file line number	Diff line number	Diff line change
`@@ -23,7 +23,10 @@ public override void Visit(IOpenApiReferenceHolder referenceHolder)`
`23`	`23`	`{`
`24`	`24`	`if (referenceHolder.Reference != null)`
`25`	`25`	`{`
`26`		`- referenceHolder.Reference.HostDocument = _currentDocument;`
	`26`	`+ referenceHolder.Reference = new OpenApiReference(referenceHolder.Reference)`
	`27`	`+ {`
	`28`	`+ HostDocument = _currentDocument,`
	`29`	`+ };`
`27`	`30`	`}`
`28`	`31`	`}`
`29`	`32`	`}`