Fix: relative references in subdirectory documents are not loading #1674

src/Microsoft.OpenApi.YamlReader/OpenApiYamlReader.cs

@@ -26,25 +26,27 @@ public class OpenApiYamlReader : IOpenApiReader
 
         /// <inheritdoc/>
         public async Task<ReadResult> ReadAsync(Stream input,
+                                                Uri location,
                                                 OpenApiReaderSettings settings,
                                                 CancellationToken cancellationToken = default)
         {
             if (input is null) throw new ArgumentNullException(nameof(input));
             if (input is MemoryStream memoryStream)
             {
-                return Read(memoryStream, settings);
+                return Read(memoryStream, location, settings);
             } 
             else 
             {
                 using var preparedStream = new MemoryStream();
                 await input.CopyToAsync(preparedStream, copyBufferSize, cancellationToken).ConfigureAwait(false);
                 preparedStream.Position = 0;
-                return Read(preparedStream, settings);
+                return Read(preparedStream, location, settings);
             }
         }
 
         /// <inheritdoc/>
         public ReadResult Read(MemoryStream input,
+                               Uri location,
                                OpenApiReaderSettings settings)
         {
             if (input is null) throw new ArgumentNullException(nameof(input));
@@ -74,13 +76,13 @@ public ReadResult Read(MemoryStream input,
                 };
             }
 
-            return Read(jsonNode, settings);
+            return Read(jsonNode, location, settings);
         }
 
         /// <inheritdoc/>
-        public static ReadResult Read(JsonNode jsonNode, OpenApiReaderSettings settings)
+        public static ReadResult Read(JsonNode jsonNode, Uri location, OpenApiReaderSettings settings)
         {
-            return _jsonReader.Read(jsonNode, settings);
+            return _jsonReader.Read(jsonNode, location, settings);
         }
 
         /// <inheritdoc/>

src/Microsoft.OpenApi/Interfaces/IOpenApiReader.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license. 
 
+using System;
 using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
@@ -18,18 +19,20 @@ public interface IOpenApiReader
         /// Async method to reads the stream and parse it into an Open API document.
         /// </summary>
         /// <param name="input">The stream input.</param>
+        /// <param name="location">Location of where the document that is getting loaded is saved</param>
         /// <param name="settings"> The OpenApi reader settings.</param>
         /// <param name="cancellationToken">Propagates notification that an operation should be cancelled.</param>
         /// <returns></returns>
-        Task<ReadResult> ReadAsync(Stream input, OpenApiReaderSettings settings, CancellationToken cancellationToken = default);
+        Task<ReadResult> ReadAsync(Stream input, Uri location, OpenApiReaderSettings settings, CancellationToken cancellationToken = default);
 
         /// <summary>
         /// Provides a synchronous method to read the input memory stream and parse it into an Open API document.
         /// </summary>
         /// <param name="input"></param>
+        /// <param name="location">Location of where the document that is getting loaded is saved</param>
         /// <param name="settings"></param>
         /// <returns></returns>
-        ReadResult Read(MemoryStream input, OpenApiReaderSettings settings);
+        ReadResult Read(MemoryStream input, Uri location, OpenApiReaderSettings settings);
 
         /// <summary>
         /// Reads the MemoryStream and parses the fragment of an OpenAPI description into an Open API Element.

src/Microsoft.OpenApi/Interfaces/IOpenApiVersionService.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 
+using System;
 using Microsoft.OpenApi.Models;
 using Microsoft.OpenApi.Reader.ParseNodes;
 
@@ -24,8 +25,9 @@ internal interface IOpenApiVersionService
         /// Converts a generic RootNode instance into a strongly typed OpenApiDocument
         /// </summary>
         /// <param name="rootNode">RootNode containing the information to be converted into an OpenAPI Document</param>
+        /// <param name="location">Location of where the document that is getting loaded is saved</param>
         /// <returns>Instance of OpenApiDocument populated with data from rootNode</returns>
-        OpenApiDocument LoadDocument(RootNode rootNode);
+        OpenApiDocument LoadDocument(RootNode rootNode, Uri location);
 
         /// <summary>
         /// Gets the description and summary scalar values in a reference object for V3.1 support

src/Microsoft.OpenApi/Interfaces/IStreamLoader.cs

@@ -17,9 +17,11 @@ public interface IStreamLoader
         /// <summary>
         /// Use Uri to locate data and convert into an input object.
         /// </summary>
+        /// <param name="baseUrl">Base URL of parent to which a relative reference could be loaded. 
+        /// If the <paramref name="uri"/> is an absolute parameter the value of this parameter will be ignored</param>
         /// <param name="uri">Identifier of some source of an OpenAPI Description</param>
         /// <param name="cancellationToken">The cancellation token.</param>
         /// <returns>A data object that can be processed by a reader to generate an <see cref="OpenApiDocument"/></returns>
-        Task<Stream> LoadAsync(Uri uri, CancellationToken cancellationToken = default);
+        Task<Stream> LoadAsync(Uri baseUrl, Uri uri, CancellationToken cancellationToken = default);
     }
 }

src/Microsoft.OpenApi/Models/OpenApiDocument.cs

@@ -110,9 +110,9 @@ public ISet<OpenApiTag>? Tags
         public IDictionary<string, object>? Metadata { get; set; }
 
         /// <summary>
-        /// Implements IBaseDocument
+        /// Absolute location of the document or a generated placeholder if location is not given
         /// </summary>
-        public Uri BaseUri { get; }
+        public Uri BaseUri { get; internal set; }
 
         /// <summary>
         /// Parameter-less constructor
@@ -572,14 +572,15 @@ private static string ConvertByteArrayToString(byte[] hash)
             }
             else
             {
-                string relativePath = OpenApiConstants.ComponentsSegment + reference.Type.GetDisplayName() + "/" + id;
+                string relativePath = $"#{OpenApiConstants.ComponentsSegment}{reference.Type.GetDisplayName()}/{id}";
+                Uri? externalResourceUri = useExternal ? Workspace?.GetDocumentId(reference.ExternalResource) : null;
 
-                uriLocation = useExternal
-                    ? Workspace?.GetDocumentId(reference.ExternalResource)?.OriginalString + relativePath
+                uriLocation = useExternal && externalResourceUri is not null
+                    ? externalResourceUri.AbsoluteUri + relativePath
                     : BaseUri + relativePath;
             }
 
-            return Workspace?.ResolveReference<IOpenApiReferenceable>(uriLocation);
+            return Workspace?.ResolveReference<IOpenApiReferenceable>(new Uri(uriLocation).AbsoluteUri);
         }
 
         /// <summary>

src/Microsoft.OpenApi/Reader/OpenApiJsonReader.cs

@@ -25,9 +25,11 @@ public class OpenApiJsonReader : IOpenApiReader
         /// Reads the memory stream input and parses it into an Open API document.
         /// </summary>
         /// <param name="input">Memory stream containing OpenAPI description to parse.</param>
+        /// <param name="location">Location of where the document that is getting loaded is saved</param>
         /// <param name="settings">The Reader settings to be used during parsing.</param>
         /// <returns></returns>
         public ReadResult Read(MemoryStream input,
+                               Uri location,
                                OpenApiReaderSettings settings)
         {
             if (input is null) throw new ArgumentNullException(nameof(input));
@@ -52,16 +54,18 @@ public ReadResult Read(MemoryStream input,
                 };
             }
 
-            return Read(jsonNode, settings);
+            return Read(jsonNode, location, settings);
         }
 
         /// <summary>
         /// Parses the JsonNode input into an Open API document.
         /// </summary>
         /// <param name="jsonNode">The JsonNode input.</param>
+        /// <param name="location">Location of where the document that is getting loaded is saved</param>
         /// <param name="settings">The Reader settings to be used during parsing.</param>
         /// <returns></returns>
         public ReadResult Read(JsonNode jsonNode,
+                               Uri location,
                                OpenApiReaderSettings settings)
         {
             if (jsonNode is null) throw new ArgumentNullException(nameof(jsonNode));
@@ -79,7 +83,7 @@ public ReadResult Read(JsonNode jsonNode,
             try
             {
                 // Parse the OpenAPI Document
-                document = context.Parse(jsonNode);
+                document = context.Parse(jsonNode, location);
                 document.SetReferenceHostDocument();
             }
             catch (OpenApiException ex)
@@ -115,10 +119,12 @@ public ReadResult Read(JsonNode jsonNode,
         /// Reads the stream input asynchronously and parses it into an Open API document.
         /// </summary>
         /// <param name="input">Memory stream containing OpenAPI description to parse.</param>
+        /// <param name="location">Location of where the document that is getting loaded is saved</param>
         /// <param name="settings">The Reader settings to be used during parsing.</param>
         /// <param name="cancellationToken">Propagates notifications that operations should be cancelled.</param>
         /// <returns></returns>
         public async Task<ReadResult> ReadAsync(Stream input,
+                                                Uri location,
                                                 OpenApiReaderSettings settings,
                                                 CancellationToken cancellationToken = default)
         {
@@ -144,7 +150,7 @@ public async Task<ReadResult> ReadAsync(Stream input,
                 };
             }
 
-            return Read(jsonNode, settings);
+            return Read(jsonNode, location, settings);
         }
 
         /// <inheritdoc/>

src/Microsoft.OpenApi/Reader/OpenApiModelFactory.cs

@@ -240,7 +240,13 @@ private static async Task<ReadResult> InternalLoadAsync(Stream input, string for
         {
             settings ??= DefaultReaderSettings.Value;
             var reader = settings.GetReader(format);
-            var readResult = await reader.ReadAsync(input, settings, cancellationToken).ConfigureAwait(false);
+            var location = new Uri(OpenApiConstants.BaseRegistryUri);
+            if (input is FileStream fileStream)
+            {
+                location = new Uri(fileStream.Name);
+            }
+
+            var readResult = await reader.ReadAsync(input, location, settings, cancellationToken).ConfigureAwait(false);
 
             if (settings.LoadExternalRefs)
             {
@@ -258,13 +264,10 @@ private static async Task<ReadResult> InternalLoadAsync(Stream input, string for
 
         private static async Task<OpenApiDiagnostic> LoadExternalRefsAsync(OpenApiDocument? document, OpenApiReaderSettings settings, string? format = null, CancellationToken token = default)
         {
-            // Create workspace for all documents to live in.
-            var baseUrl = settings.BaseUrl ?? new Uri(OpenApiConstants.BaseRegistryUri);
-            var openApiWorkSpace = new OpenApiWorkspace(baseUrl);
-
-            // Load this root document into the workspace
-            var streamLoader = new DefaultStreamLoader(baseUrl, settings.HttpClient);
-            var workspaceLoader = new OpenApiWorkspaceLoader(openApiWorkSpace, settings.CustomExternalLoader ?? streamLoader, settings);
+            // Load this document into the workspace
+            var streamLoader = new DefaultStreamLoader(settings.HttpClient);
+            var workspace = document?.Workspace ?? new OpenApiWorkspace();
+            var workspaceLoader = new OpenApiWorkspaceLoader(workspace, settings.CustomExternalLoader ?? streamLoader, settings);
             return await workspaceLoader.LoadAsync(new OpenApiReference() { ExternalResource = "/" }, document, format ?? OpenApiConstants.Json, null, token).ConfigureAwait(false);
         }
 
@@ -280,8 +283,9 @@ private static ReadResult InternalLoad(MemoryStream input, string format, OpenAp
                 throw new ArgumentException($"Cannot parse the stream: {nameof(input)} is empty or contains no elements.");
             }
 
+            var location = new Uri(OpenApiConstants.BaseRegistryUri);
             var reader = settings.GetReader(format);
-            var readResult = reader.Read(input, settings);
+            var readResult = reader.Read(input, location, settings);
             return readResult;
         }
 

src/Microsoft.OpenApi/Reader/ParsingContext.cs

@@ -62,8 +62,9 @@ public ParsingContext(OpenApiDiagnostic diagnostic)
         /// Initiates the parsing process.  Not thread safe and should only be called once on a parsing context
         /// </summary>
         /// <param name="jsonNode">Set of Json nodes to parse.</param>
+        /// <param name="location">Location of where the document that is getting loaded is saved</param>
         /// <returns>An OpenApiDocument populated based on the passed yamlDocument </returns>
-        public OpenApiDocument Parse(JsonNode jsonNode)
+        public OpenApiDocument Parse(JsonNode jsonNode, Uri location)
         {
             RootNode = new RootNode(this, jsonNode);
 
@@ -75,20 +76,20 @@ public OpenApiDocument Parse(JsonNode jsonNode)
             {
                 case string version when version.is2_0():
                     VersionService = new OpenApiV2VersionService(Diagnostic);
-                    doc = VersionService.LoadDocument(RootNode);
+                    doc = VersionService.LoadDocument(RootNode, location);
                     this.Diagnostic.SpecificationVersion = OpenApiSpecVersion.OpenApi2_0;
                     ValidateRequiredFields(doc, version);
                     break;
 
                 case string version when version.is3_0():
                     VersionService = new OpenApiV3VersionService(Diagnostic);
-                    doc = VersionService.LoadDocument(RootNode);
+                    doc = VersionService.LoadDocument(RootNode, location);
                     this.Diagnostic.SpecificationVersion = version.is3_1() ? OpenApiSpecVersion.OpenApi3_1 : OpenApiSpecVersion.OpenApi3_0;
                     ValidateRequiredFields(doc, version);
                     break;
                 case string version when version.is3_1():
                     VersionService = new OpenApiV31VersionService(Diagnostic);
-                    doc = VersionService.LoadDocument(RootNode);
+                    doc = VersionService.LoadDocument(RootNode, location);
                     this.Diagnostic.SpecificationVersion = OpenApiSpecVersion.OpenApi3_1;
                     ValidateRequiredFields(doc, version);
                     break;

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

@@ -17,30 +17,24 @@
     /// </summary>
     public class DefaultStreamLoader : IStreamLoader
     {
-        private readonly Uri baseUrl;
         private readonly HttpClient _httpClient;
 
         /// <summary>
         /// The default stream loader
         /// </summary>
-        /// <param name="baseUrl"></param>
         /// <param name="httpClient">The HttpClient to use to retrieve documents when needed</param>
-        public DefaultStreamLoader(Uri baseUrl, HttpClient httpClient)
+        public DefaultStreamLoader(HttpClient httpClient)
         {
-            this.baseUrl = baseUrl;
             _httpClient = Utils.CheckArgumentNull(httpClient);
         }
 
         /// <inheritdoc/>
-        public async Task<Stream> LoadAsync(Uri uri, CancellationToken cancellationToken = default)
+        public async Task<Stream> LoadAsync(Uri baseUrl, Uri uri, CancellationToken cancellationToken = default)
         {
-            var absoluteUri = (baseUrl.AbsoluteUri.Equals(OpenApiConstants.BaseRegistryUri), baseUrl.IsAbsoluteUri, uri.IsAbsoluteUri) switch
+            var absoluteUri = baseUrl.AbsoluteUri.Equals(OpenApiConstants.BaseRegistryUri) switch
             {
-                (true, _, _) => new Uri(Path.Combine(Directory.GetCurrentDirectory(), uri.ToString())),
-                // this overcomes a URI concatenation issue for local paths on linux OSes
-                (_, true, false) when baseUrl.Scheme.Equals("file", StringComparison.OrdinalIgnoreCase) && !RuntimeInformation.IsOSPlatform(OSPlatform.Windows) =>
-                    new Uri(Path.Combine(baseUrl.AbsoluteUri, uri.ToString())),
-                (_, _, _) => new Uri(baseUrl, uri),
+                true => new Uri(Path.Combine(Directory.GetCurrentDirectory(), uri.ToString())),
+                _ => new Uri(baseUrl, uri),
             };
 
             return absoluteUri.Scheme switch

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

@@ -48,7 +48,8 @@ internal async Task<OpenApiDiagnostic> LoadAsync(OpenApiReference reference,
                 // If not already in workspace, load it and process references
                 if (item.ExternalResource is not null && !_workspace.Contains(item.ExternalResource))
                 {
-                    var input = await _loader.LoadAsync(new(item.ExternalResource, UriKind.RelativeOrAbsolute), cancellationToken).ConfigureAwait(false);
+                    var uri = new Uri(item.ExternalResource, UriKind.RelativeOrAbsolute);
+                    var input = await _loader.LoadAsync(item.HostDocument!.BaseUri, uri, cancellationToken).ConfigureAwait(false);
                     var result = await OpenApiDocument.LoadAsync(input, format, _readerSettings, cancellationToken).ConfigureAwait(false);
                     // Merge diagnostics
                     if (result.Diagnostic != null)

src/Microsoft.OpenApi/Reader/V2/OpenApiDocumentDeserializer.cs

@@ -227,9 +227,12 @@ private static string BuildUrl(string? scheme, string? host, string? basePath)
             return uriBuilder.ToString();
         }
 
-        public static OpenApiDocument LoadOpenApi(RootNode rootNode)
+        public static OpenApiDocument LoadOpenApi(RootNode rootNode, Uri location)
         {
-            var openApiDoc = new OpenApiDocument();
+            var openApiDoc = new OpenApiDocument
+            {
+                BaseUri = location
+            };
 
             var openApiNode = rootNode.GetMap();
 

src/Microsoft.OpenApi/Reader/V2/OpenApiV2VersionService.cs

@@ -50,9 +50,9 @@ public OpenApiV2VersionService(OpenApiDiagnostic diagnostic)
             [typeof(OpenApiXml)] = OpenApiV2Deserializer.LoadXml
         };
 
-        public OpenApiDocument LoadDocument(RootNode rootNode)
+        public OpenApiDocument LoadDocument(RootNode rootNode, Uri location)
         {
-            return OpenApiV2Deserializer.LoadOpenApi(rootNode);
+            return OpenApiV2Deserializer.LoadOpenApi(rootNode, location);
         }
 
         public T? LoadElement<T>(ParseNode node, OpenApiDocument doc) where T : IOpenApiElement

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

@@ -38,9 +38,12 @@ internal static partial class OpenApiV3Deserializer
             {s => s.StartsWith(OpenApiConstants.ExtensionFieldNamePrefix, StringComparison.OrdinalIgnoreCase), (o, p, n, _) => o.AddExtension(p, LoadExtension(p, n))}
         };
 
-        public static OpenApiDocument LoadOpenApi(RootNode rootNode)
+        public static OpenApiDocument LoadOpenApi(RootNode rootNode, Uri location)
         {
-            var openApiDoc = new OpenApiDocument();
+            var openApiDoc = new OpenApiDocument
+            {
+                BaseUri = location
+            };
             var openApiNode = rootNode.GetMap();
 
             ParseMap(openApiNode, openApiDoc, _openApiFixedFields, _openApiPatternFields, openApiDoc);

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

@@ -64,9 +64,9 @@ public OpenApiV3VersionService(OpenApiDiagnostic diagnostic)
             [typeof(OpenApiSchemaReference)] = OpenApiV3Deserializer.LoadMapping
         };
 
-        public OpenApiDocument LoadDocument(RootNode rootNode)
+        public OpenApiDocument LoadDocument(RootNode rootNode, Uri location)
         {
-            return OpenApiV3Deserializer.LoadOpenApi(rootNode);
+            return OpenApiV3Deserializer.LoadOpenApi(rootNode, location);
         }
 
         public T LoadElement<T>(ParseNode node, OpenApiDocument doc) where T : IOpenApiElement