feat: adds the detected format as part of the result

Signed-off-by: Vincent Biret <vibiret@microsoft.com>

Author: baywet

src/Microsoft.OpenApi.YamlReader/OpenApiYamlReader.cs

@@ -31,14 +31,14 @@ public async Task<ReadResult> ReadAsync(Stream input,
             if (input is null) throw new ArgumentNullException(nameof(input));
             if (input is MemoryStream memoryStream)
             {
-                return Read(memoryStream, location, settings);
+                return UpdateFormat(Read(memoryStream, location, settings));
             } 
             else 
             {
                 using var preparedStream = new MemoryStream();
                 await input.CopyToAsync(preparedStream, copyBufferSize, cancellationToken).ConfigureAwait(false);
                 preparedStream.Position = 0;
-                return Read(preparedStream, location, settings);
+                return UpdateFormat(Read(preparedStream, location, settings));
             }
         }
 
@@ -70,17 +70,23 @@ public ReadResult Read(MemoryStream input,
                 return new()
                 {
                     Document = null,
-                    Diagnostic = diagnostic
+                    Diagnostic = diagnostic,
+                    Format = OpenApiConstants.Yaml,
                 };
             }
 
-            return Read(jsonNode, location, settings);
+            return UpdateFormat(Read(jsonNode, location, settings));
+        }
+        private static ReadResult UpdateFormat(ReadResult result)
+        {
+            result.Format = OpenApiConstants.Yaml;
+            return result;
         }
 
         /// <inheritdoc/>
         public static ReadResult Read(JsonNode jsonNode, Uri location, OpenApiReaderSettings settings)
         {
-            return _jsonReader.Read(jsonNode, location, settings);
+            return UpdateFormat(_jsonReader.Read(jsonNode, location, settings));
         }
 
         /// <inheritdoc/>

src/Microsoft.OpenApi/Reader/OpenApiJsonReader.cs

@@ -45,7 +45,8 @@ public ReadResult Read(MemoryStream input,
                 return new ReadResult
                 {
                     Document = null,
-                    Diagnostic = diagnostic
+                    Diagnostic = diagnostic,
+                    Format = OpenApiConstants.Json,
                 };
             }
 
@@ -106,7 +107,8 @@ public ReadResult Read(JsonNode jsonNode,
             return new()
             {
                 Document = document,
-                Diagnostic = diagnostic
+                Diagnostic = diagnostic,
+                Format = OpenApiConstants.Json
             };
         }
 
@@ -141,7 +143,8 @@ public async Task<ReadResult> ReadAsync(Stream input,
                 return new ReadResult
                 {
                     Document = null,
-                    Diagnostic = diagnostic
+                    Diagnostic = diagnostic,
+                    Format = OpenApiConstants.Json,
                 };
             }
 

src/Microsoft.OpenApi/Reader/ReadResult.cs

@@ -16,12 +16,24 @@ public class ReadResult
     /// </summary>
     public OpenApiDiagnostic? Diagnostic { get; set; }
     /// <summary>
+    /// The format of the OpenAPI document (e.g., "json", "yaml").
+    /// </summary>
+    public string? Format { get; set; }
+    /// <summary>
     /// Deconstructs the result for easier assignment on the client application.
     /// </summary>
     public void Deconstruct(out OpenApiDocument? document, out OpenApiDiagnostic? diagnostic)
+    {
+        Deconstruct(out document, out diagnostic, out _);
+    }
+    /// <summary>
+    /// Deconstructs the result for easier assignment on the client application.
+    /// </summary>
+    public void Deconstruct(out OpenApiDocument? document, out OpenApiDiagnostic? diagnostic, out string? format)
     {
         document = Document;
         diagnostic = Diagnostic;
+        format = Format;
     }
 }
 

test/Microsoft.OpenApi.Readers.Tests/OpenApiReaderTests/OpenApiStreamReaderTests.cs

@@ -20,8 +20,9 @@ public async Task StreamShouldCloseIfLeaveStreamOpenSettingEqualsFalse()
             using var stream = Resources.GetStream(Path.Combine(SampleFolderPath, "petStore.yaml"));
             var settings = new OpenApiReaderSettings { LeaveStreamOpen = false };
             settings.AddYamlReader();
-            _ = await OpenApiDocument.LoadAsync(stream, settings: settings);
+            (_, _, var format) = await OpenApiDocument.LoadAsync(stream, settings: settings);
             Assert.False(stream.CanRead);
+            Assert.Equal(OpenApiConstants.Yaml, format);
         }
 
         [Fact]

test/Microsoft.OpenApi.Tests/PublicApi/PublicApi.approved.txt

@@ -2007,6 +2007,8 @@ namespace Microsoft.OpenApi.Reader
         public ReadResult() { }
         public Microsoft.OpenApi.Reader.OpenApiDiagnostic? Diagnostic { get; set; }
         public Microsoft.OpenApi.OpenApiDocument? Document { get; set; }
+        public string? Format { get; set; }
         public void Deconstruct(out Microsoft.OpenApi.OpenApiDocument? document, out Microsoft.OpenApi.Reader.OpenApiDiagnostic? diagnostic) { }
+        public void Deconstruct(out Microsoft.OpenApi.OpenApiDocument? document, out Microsoft.OpenApi.Reader.OpenApiDiagnostic? diagnostic, out string? format) { }
     }
 }

test/Microsoft.OpenApi.Tests/Reader/OpenApiModelFactoryTests.cs

@@ -114,6 +114,7 @@ await File.WriteAllTextAsync(tempFilePathReferrer,
             BaseUrl = baseUri, 
         };
         var readResult = await OpenApiDocument.LoadAsync(stream, settings: settings);
+        Assert.Equal(OpenApiConstants.Json, readResult.Format);
         Assert.NotNull(readResult.Document);
         Assert.NotNull(readResult.Document.Components);
         Assert.Equal(baseUri, readResult.Document.BaseUri);