Register local refs within external documents with unique GUID

Author: irvinesunday

src/Microsoft.OpenApi/Reader/Services/OpenApiRemoteReferenceCollector.cs

@@ -1,6 +1,7 @@
 // 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;
@@ -14,6 +15,7 @@ namespace Microsoft.OpenApi.Reader.Services
     internal class OpenApiRemoteReferenceCollector : OpenApiVisitorBase
     {
         private readonly Dictionary<string, OpenApiReference> _references = new();
+        private Guid _guid = new();
 
         /// <summary>
         /// List of external references collected from OpenApiDocument
@@ -32,19 +34,30 @@ public IEnumerable<OpenApiReference> References
         /// <param name="referenceable"></param>
         public override void Visit(IOpenApiReferenceable referenceable)
         {
-            AddReference(referenceable.Reference);
+            AddExternalReference(referenceable.Reference);
+            AddLocalReference(referenceable.Reference);
         }
 
         /// <summary>
         /// Collect external reference
         /// </summary>
-        private void AddReference(OpenApiReference reference)
+        private void AddExternalReference(OpenApiReference reference)
         {
             if (reference is {IsExternal: true} &&
                 !_references.ContainsKey(reference.ExternalResource))
             {
                 _references.Add(reference.ExternalResource, reference);
             }
         }
+
+        private void AddLocalReference(OpenApiReference reference)
+        {
+            if (reference is { IsExternal: false } &&
+                !_references.ContainsKey(reference.ReferenceV3))
+            {
+                reference.ExternalResource = _guid.ToString();
+                _references.Add(reference.ReferenceV3, reference);
+            }
+        }
     }
 }

src/Microsoft.OpenApi/Reader/Services/OpenApiWorkspaceLoader.cs

@@ -39,21 +39,32 @@ internal async Task<OpenApiDiagnostic> LoadAsync(OpenApiReference reference,
             // Walk references
             foreach (var item in referenceCollector.References)
             {
+
                 // If not already in workspace, load it and process references
                 if (!_workspace.Contains(item.ExternalResource))
                 {
-                    var input = await _loader.LoadAsync(new(item.ExternalResource, UriKind.RelativeOrAbsolute));
-                    var result = await OpenApiDocument.LoadAsync(input, format, _readerSettings, cancellationToken);
-                    // Merge diagnostics
-                    if (result.OpenApiDiagnostic != null)
+                    if (!Guid.TryParse(item.ExternalResource, out _))
                     {
-                        diagnostic.AppendDiagnostic(result.OpenApiDiagnostic, item.ExternalResource);
+                        var input = await _loader.LoadAsync(new(item.ExternalResource, UriKind.RelativeOrAbsolute));
+                        var result = await OpenApiDocument.LoadAsync(input, format, _readerSettings, cancellationToken);
+                        // Merge diagnostics
+                        if (result.OpenApiDiagnostic != null)
+                        {
+                            diagnostic.AppendDiagnostic(result.OpenApiDiagnostic, item.ExternalResource);
+                        }
+                        if (result.OpenApiDocument != null)
+                        {
+                            var loadDiagnostic = await LoadAsync(item, result.OpenApiDocument, format, diagnostic, cancellationToken);
+                            diagnostic = loadDiagnostic;
+                        }
                     }
-                    if (result.OpenApiDocument != null)
+                    else // local ref in an external file, add this to the documents registry
                     {
-                        var loadDiagnostic = await LoadAsync(item, result.OpenApiDocument, format,  diagnostic, cancellationToken);
-                        diagnostic = loadDiagnostic;
-                    }
+                        if (!_workspace.Contains(item.ExternalResource))
+                        {
+                            _workspace.AddDocument(reference.ExternalResource, document);
+                        }
+                    }                    
                 }
             }