Respect LowercaseUrls in ApiExplorer

Fixes #8006

src/Microsoft.AspNetCore.Mvc.ApiExplorer/DefaultApiDescriptionProvider.cs

@@ -26,6 +26,7 @@ namespace Microsoft.AspNetCore.Mvc.ApiExplorer
         private readonly MvcOptions _mvcOptions;
         private readonly IActionResultTypeMapper _mapper;
         private readonly ApiResponseTypeProvider _responseTypeProvider;
+        private readonly RouteOptions _routeOptions;
         private readonly IInlineConstraintResolver _constraintResolver;
         private readonly IModelMetadataProvider _modelMetadataProvider;
 
@@ -53,6 +54,7 @@ namespace Microsoft.AspNetCore.Mvc.ApiExplorer
         /// constraints.</param>
         /// <param name="modelMetadataProvider">The <see cref="IModelMetadataProvider"/>.</param>
         /// <param name="mapper"> The <see cref="IActionResultTypeMapper"/>.</param>
+        [Obsolete("This constructor is obsolete and will be removed in a future release.")]
         public DefaultApiDescriptionProvider(
             IOptions<MvcOptions> optionsAccessor,
             IInlineConstraintResolver constraintResolver,
@@ -66,6 +68,30 @@ namespace Microsoft.AspNetCore.Mvc.ApiExplorer
             _responseTypeProvider = new ApiResponseTypeProvider(modelMetadataProvider, mapper, _mvcOptions);
         }
 
+        /// <summary>
+        /// Creates a new instance of <see cref="DefaultApiDescriptionProvider"/>.
+        /// </summary>
+        /// <param name="optionsAccessor">The accessor for <see cref="MvcOptions"/>.</param>
+        /// <param name="constraintResolver">The <see cref="IInlineConstraintResolver"/> used for resolving inline
+        /// constraints.</param>
+        /// <param name="modelMetadataProvider">The <see cref="IModelMetadataProvider"/>.</param>
+        /// <param name="mapper"> The <see cref="IActionResultTypeMapper"/>.</param>
+        /// <param name="routeOptions">The accessor for <see cref="RouteOptions"/>.</param>
+        public DefaultApiDescriptionProvider(
+            IOptions<MvcOptions> optionsAccessor,
+            IInlineConstraintResolver constraintResolver,
+            IModelMetadataProvider modelMetadataProvider,
+            IActionResultTypeMapper mapper,
+            IOptions<RouteOptions> routeOptions)
+        {
+            _mvcOptions = optionsAccessor.Value;
+            _constraintResolver = constraintResolver;
+            _modelMetadataProvider = modelMetadataProvider;
+            _mapper = mapper;
+            _responseTypeProvider = new ApiResponseTypeProvider(modelMetadataProvider, mapper, _mvcOptions);
+            _routeOptions = routeOptions.Value;
+        }
+
         /// <inheritdoc />
         public int Order => -1000;
 
@@ -383,7 +409,9 @@ namespace Microsoft.AspNetCore.Mvc.ApiExplorer
                 {
                     if (part.IsLiteral)
                     {
-                        currentSegment += part.Text;
+                        currentSegment += _routeOptions.LowercaseUrls ?
+                            part.Text.ToLowerInvariant() :
+                            part.Text;
                     }
                     else if (part.IsParameter)
                     {

test/Microsoft.AspNetCore.Mvc.ApiExplorer.Test/DefaultApiDescriptionProviderTest.cs

@@ -387,6 +387,25 @@ namespace Microsoft.AspNetCore.Mvc.Description
             Assert.Single(description.ParameterDescriptions, p => p.Name == "id5");
         }
 
+        [Fact]
+        public void GetApiDescription_ProducesLowerCaseRelativePaths()
+        {
+            // Arrange
+            var action = CreateActionDescriptor();
+            action.AttributeRouteInfo = new AttributeRouteInfo
+            {
+                Template = "api/Products/UpdateProduct/{productId}"
+            };
+            var routeOptions = new RouteOptions { LowercaseUrls = true };
+
+            // Act
+            var descriptions = GetApiDescriptions(action, routeOptions: routeOptions);
+
+            // Assert
+            var description = Assert.Single(descriptions);
+            Assert.Equal("api/products/updateproduct/{productId}", description.RelativePath);
+        }
+
         [Fact]
         public void GetApiDescription_PopulatesResponseType_WithProduct()
         {
@@ -1797,7 +1816,8 @@ namespace Microsoft.AspNetCore.Mvc.Description
             ActionDescriptor action,
             List<MockInputFormatter> inputFormatters = null,
             List<MockOutputFormatter> outputFormatters = null,
-            bool allowValidatingTopLevelNodes = true)
+            bool allowValidatingTopLevelNodes = true,
+            RouteOptions routeOptions = null)
         {
             var context = new ApiDescriptionProviderContext(new ActionDescriptor[] { action });
 
@@ -1827,7 +1847,8 @@ namespace Microsoft.AspNetCore.Mvc.Description
                 optionsAccessor,
                 constraintResolver.Object,
                 modelMetadataProvider,
-                new ActionResultTypeMapper());
+                new ActionResultTypeMapper(),
+                Options.Create(routeOptions ?? new RouteOptions()));
 
             provider.OnProvidersExecuting(context);
             provider.OnProvidersExecuted(context);