Fixes empty response objects for OData type cast paths (#547)

* Refactor response method; update conditionality

* Revert creating response content of collections

This will been created in the response section

* Update integration tests

* Update release notes

* Remove unnecessary whitespace

* Update release note text

* PR review fix

Check for: Context.Settings.EnableDerivedTypesReferencesForResponses

Author: irvinesunday

src/Microsoft.OpenApi.OData.Reader/Microsoft.OpenAPI.OData.Reader.csproj

@@ -15,13 +15,13 @@
     <TargetFrameworks>netstandard2.0</TargetFrameworks>
     <PackageId>Microsoft.OpenApi.OData</PackageId>
     <SignAssembly>true</SignAssembly>
-    <Version>1.6.6</Version>
+    <Version>1.6.7</Version>
     <Description>This package contains the codes you need to convert OData CSDL to Open API Document of Model.</Description>
     <Copyright>© Microsoft Corporation. All rights reserved.</Copyright>
     <PackageTags>Microsoft OpenApi OData EDM</PackageTags>
     <RepositoryUrl>https://github.com/Microsoft/OpenAPI.NET.OData</RepositoryUrl>
     <PackageReleaseNotes>
-		- Adds support for IndexableByKey restrictions annotations on entity sets #541
+		- Fixes empty response objects for OData type cast paths. #546
 	</PackageReleaseNotes>
     <AssemblyName>Microsoft.OpenApi.OData.Reader</AssemblyName>
     <AssemblyOriginatorKeyFile>..\..\tool\Microsoft.OpenApi.OData.snk</AssemblyOriginatorKeyFile>

src/Microsoft.OpenApi.OData.Reader/Operation/ComplexPropertyGetOperationHandler.cs

@@ -143,39 +143,13 @@ protected override void SetExtensions(OpenApiOperation operation)
     /// <inheritdoc/>
     protected override void SetResponses(OpenApiOperation operation)
     {
-        if(ComplexPropertySegment.Property.Type.IsCollection())
-            SetCollectionResponse(operation);
-        else
-            SetSingleResponse(operation);
-        operation.AddErrorResponses(Context.Settings, false);
-
-        base.SetResponses(operation);
-    }
-    private void SetCollectionResponse(OpenApiOperation operation)
-    {
-        operation.Responses = new OpenApiResponses
+        if (ComplexPropertySegment.Property.Type.IsCollection())
         {
-            {
-                Context.Settings.UseSuccessStatusCodeRange ? Constants.StatusCodeClass2XX : Constants.StatusCode200,
-                new OpenApiResponse
-                {
-                    UnresolvedReference = true,
-                    Reference = new OpenApiReference()
-                    {
-                        Type = ReferenceType.Response,
-                        Id = $"{ComplexPropertySegment.ComplexType.FullName()}{Constants.CollectionSchemaSuffix}"
-                    },
-                }
-            }
-        };
-    }
-    private void SetSingleResponse(OpenApiOperation operation)
-    {
-        OpenApiSchema schema = null;
-
-        if (schema == null)
+            SetCollectionResponse(operation, ComplexPropertySegment.ComplexType.FullName());
+        }
+        else
         {
-            schema = new OpenApiSchema
+            OpenApiSchema schema = new()
             {
                 UnresolvedReference = true,
                 Reference = new OpenApiReference
@@ -184,28 +158,14 @@ private void SetSingleResponse(OpenApiOperation operation)
                     Id = ComplexPropertySegment.ComplexType.FullName()
                 }
             };
+
+            SetSingleResponse(operation, schema);
         }
-        operation.Responses = new OpenApiResponses
-        {
-            {
-                Context.Settings.UseSuccessStatusCodeRange ? Constants.StatusCodeClass2XX : Constants.StatusCode200,
-                new OpenApiResponse
-                {
-                    Description = "Result entities",
-                    Content = new Dictionary<string, OpenApiMediaType>
-                    {
-                        {
-                            Constants.ApplicationJsonMediaType,
-                            new OpenApiMediaType
-                            {
-                                Schema = schema
-                            }
-                        }
-                    },
-                }
-            }
-        };
+
+        operation.AddErrorResponses(Context.Settings, false);
+        base.SetResponses(operation);
     }
+   
     protected override void SetSecurity(OpenApiOperation operation)
     {
         if (_readRestrictions?.Permissions == null)

src/Microsoft.OpenApi.OData.Reader/Operation/ODataTypeCastGetOperationHandler.cs

@@ -34,10 +34,13 @@ internal class ODataTypeCastGetOperationHandler : OperationHandler
 
     private bool isKeySegment;
 
+	private bool secondLastSegmentIsComplexProperty;
+
 	private bool IsSingleElement 
 	{
 		get => isKeySegment ||
-				singleton != null ||
+				secondLastSegmentIsComplexProperty ||
+                singleton != null ||
 					(navigationProperty != null &&
 					!navigationProperty.Type.IsCollection() &&
 					entitySet == null);
@@ -62,7 +65,8 @@ protected override void Initialize(ODataContext context, ODataPath path)
 		// reseting the fields as we're reusing the handler
 		singleton = null;
 		isKeySegment = false;
-		restriction = null;
+		secondLastSegmentIsComplexProperty = false;
+        restriction = null;
 		entitySet = null;
 		navigationProperty = null;
 		parentStructuredType = null;
@@ -102,6 +106,10 @@ protected override void Initialize(ODataContext context, ODataPath path)
 				SetAnnotatableRestrictionFromNavigationSourceSegment(sourceSegment1);
             }
 		}
+		else if (SecondLastSegment is ODataComplexPropertySegment)
+		{
+			secondLastSegmentIsComplexProperty = true;
+		}
 
 		if (path.Last() is ODataTypeCastSegment odataTypeCastSegment)
 		{
@@ -187,77 +195,39 @@ protected override void SetBasicInfo(OpenApiOperation operation)
 
 	/// <inheritdoc/>
 	protected override void SetResponses(OpenApiOperation operation)
-	{
-		if (IsSingleElement)
-			SetSingleResponse(operation);
-		else
-			SetCollectionResponse(operation);
+    {
+        if (IsSingleElement)
+		{
+            OpenApiSchema schema = null;
 
-		operation.AddErrorResponses(Context.Settings, false);
+            if (Context.Settings.EnableDerivedTypesReferencesForResponses)
+            {
+                schema = EdmModelHelper.GetDerivedTypesReferenceSchema(targetStructuredType, Context.Model);
+            }
 
-		base.SetResponses(operation);
-	}
+            if (schema == null)
+            {
+                schema = new OpenApiSchema
+                {
+                    UnresolvedReference = true,
+                    Reference = new OpenApiReference
+                    {
+                        Type = ReferenceType.Schema,
+                        Id = TargetSchemaElement.FullName()
+                    }
+                };
+            }
 
-	private void SetCollectionResponse(OpenApiOperation operation)
-	{
-		operation.Responses = new OpenApiResponses
+            SetSingleResponse(operation, schema);
+        }
+		else
 		{
-			{
-				Context.Settings.UseSuccessStatusCodeRange ? Constants.StatusCodeClass2XX : Constants.StatusCode200,
-				new OpenApiResponse
-				{
-					UnresolvedReference = true,
-					Reference = new OpenApiReference()
-					{
-						Type = ReferenceType.Response,
-						Id = $"{TargetSchemaElement.FullName()}{Constants.CollectionSchemaSuffix}"
-					},
-				}
-			}
-		};
-	}
-
-	private void SetSingleResponse(OpenApiOperation operation)
-	{
-		OpenApiSchema schema = null;
+            SetCollectionResponse(operation, TargetSchemaElement.FullName());
+        }			
 
-		if (Context.Settings.EnableDerivedTypesReferencesForResponses)
-		{
-			schema = EdmModelHelper.GetDerivedTypesReferenceSchema(targetStructuredType, Context.Model);
-		}
+		operation.AddErrorResponses(Context.Settings, false);
 
-		if (schema == null)
-		{
-			schema = new OpenApiSchema
-			{
-				UnresolvedReference = true,
-				Reference = new OpenApiReference
-				{
-					Type = ReferenceType.Schema,
-					Id = TargetSchemaElement.FullName()
-				}
-			};
-		}
-		operation.Responses = new OpenApiResponses
-		{
-			{
-				Context.Settings.UseSuccessStatusCodeRange ? Constants.StatusCodeClass2XX : Constants.StatusCode200,
-				new OpenApiResponse
-				{
-					Description = "Result entities",
-					Content = new Dictionary<string, OpenApiMediaType>
-					{
-						{
-							Constants.ApplicationJsonMediaType,
-							new OpenApiMediaType
-							{
-								Schema = schema
-							}
-						}
-					},
-				}
-			}
-		};
+		base.SetResponses(operation);
 	}
 
 	/// <inheritdoc/>

src/Microsoft.OpenApi.OData.Reader/Operation/OperationHandler.cs

@@ -5,8 +5,6 @@
 
 using System.Collections.Generic;
 using System.Linq;
-using Microsoft.OData.Edm;
-using System.Text;
 using Microsoft.OpenApi.Any;
 using Microsoft.OpenApi.MicrosoftExtensions;
 using Microsoft.OpenApi.Models;
@@ -298,5 +296,53 @@ protected virtual void SetCustomLinkRelType()
             }
         }
 
+        internal void SetCollectionResponse(OpenApiOperation operation, string targetElementFullName)
+        {
+            Utils.CheckArgumentNull(operation, nameof(operation));
+            Utils.CheckArgumentNullOrEmpty(targetElementFullName, nameof(targetElementFullName));            
+
+            operation.Responses = new OpenApiResponses
+            {
+                {
+                    Context.Settings.UseSuccessStatusCodeRange ? Constants.StatusCodeClass2XX : Constants.StatusCode200,
+                    new OpenApiResponse
+                    {
+                        UnresolvedReference = true,
+                        Reference = new OpenApiReference()
+                        {
+                            Type = ReferenceType.Response,
+                            Id = $"{targetElementFullName}{Constants.CollectionSchemaSuffix}"
+                        }
+                    }
+                }
+            };
+        }
+
+        internal void SetSingleResponse(OpenApiOperation operation, OpenApiSchema schema)
+        {
+            Utils.CheckArgumentNull(operation, nameof(operation));
+            Utils.CheckArgumentNull(schema, nameof(schema));
+            
+            operation.Responses = new OpenApiResponses
+            {
+                {
+                    Context.Settings.UseSuccessStatusCodeRange ? Constants.StatusCodeClass2XX : Constants.StatusCode200,
+                    new OpenApiResponse
+                    {
+                        Description = "Entity result.",
+                        Content = new Dictionary<string, OpenApiMediaType>
+                        {
+                            {
+                                Constants.ApplicationJsonMediaType,
+                                new OpenApiMediaType
+                                {
+                                    Schema = schema
+                                }
+                            }
+                        },
+                    }
+                }
+            };
+        }
     }
 }