Merge branch 'improvement/ItemConfiguration-refactoring' into develop

Refactored the `ItemConfiguration` class to be a property of `ItemMetadata`. Since the vast majority of the properties on `ItemConfiguration` don't change at runtime (since they map to `[Attribute]` values), it makes sense to evaluate them once and then cache them with their corresponding `ItemMetadata` instance. This also allows us to "flip the script" on how we pass metadata within the mapping services: Previously, we passed an `ItemConfiguration` (or `PropertyConfiguration`) instance, through which recipients could access the `ItemMetadata` (or `PropertyAccessor`); now, the `ItemMetadata` (or `PropertyAccessor`) is relayed within the mapping services, through which recipients can access the `ItemConfiguration` property. In practice, this is a more intuitive data model, and should be faster.

The one element of `ItemConfiguration` that did change at runtime was the `attributePrefix`, which was previously factored into the `ItemConfiguration.AttributeKey` property. Since this can't be factored into the cached `ItemMetadata.Configuration` reference, it must be relayed independently within the mapping services. This has been added to most of the method signatures within `TopicMappingService` and `ReverseTopicMappingService` (and its dependent `BindingModelValidator`). Further, a new `GetCompositeAttributeKey()` convenience method was introduced to centralize how the concatenation of the `attributePrefix` and `AttributeKey` should work.

Finally, this allowed us to remove the `PropertyConfiguration` entirely. The one remaining dependency on it—the `Validate` method—has been moved to `MemberAccessor`.

Author: JeremyCaney

OnTopic.AspNetCore.Mvc.Tests/ErrorControllerTest.cs

@@ -58,8 +58,8 @@ public ErrorControllerTest(TestTopicRepository topicRepository) {
     | TEST: ERROR CONTROLLER: HTTP: RETURNS EXPECTED ERROR
     \-------------------------------------------------------------------------------------------------------------------------*/
     /// <summary>
-    ///   Triggers the <see cref="ErrorController.HttpAsync(Int32)" /> action with different status codes, and ensures that the
-    ///   expected <see cref="Topic"/> is returned in the <see cref="TopicViewResult"/>.
+    ///   Triggers the <see cref="ErrorController.HttpAsync(Int32, Boolean)" /> action with different status codes, and ensures
+    ///   that the expected <see cref="Topic"/> is returned in the <see cref="TopicViewResult"/>.
     /// </summary>
     [Theory]
     [InlineData(405, "405")]                               // Exact match

OnTopic/Internal/Reflection/ItemMetadata.cs

@@ -6,6 +6,9 @@
 using System.Collections;
 using System.Reflection;
 using OnTopic.Attributes;
+using OnTopic.Mapping;
+using OnTopic.Mapping.Internal;
+using OnTopic.Mapping.Reverse;
 
 namespace OnTopic.Internal.Reflection {
 
@@ -24,6 +27,7 @@ internal abstract class ItemMetadata {
     private readonly            ICustomAttributeProvider        _attributeProvider;
     private readonly            Type                            _type                           = default!;
     private                     List<Attribute>                 _customAttributes               = default!;
+    private                     ItemConfiguration?              _itemConfiguration;
 
     /*==========================================================================================================================
     | CONSTRUCTOR
@@ -102,6 +106,26 @@ bool isList()
       }
     }
 
+    /*==========================================================================================================================
+    | CONFIGURATION
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Gets a reference to the configuration settings for the current item, based on the annotations configured in the code.
+    /// </summary>
+    /// <remarks>
+    ///   The <see cref="ItemConfiguration"/> class identifies annotations used by the <see cref="TopicMappingService"/> and the
+    ///   <see cref="ReverseTopicMappingService"/>. While it can be called on any <see cref="Type"/>, it is only expected to
+    ///   offer a benefit for model classes intended for mapping.
+    /// </remarks>
+    internal ItemConfiguration Configuration {
+      get {
+        if (_itemConfiguration is null) {
+          _itemConfiguration = new(this);
+        }
+        return _itemConfiguration;
+      }
+    }
+
     /*==========================================================================================================================
     | IS NULLABLE?
     \-------------------------------------------------------------------------------------------------------------------------*/

OnTopic/Internal/Reflection/MemberAccessor.cs

@@ -3,6 +3,7 @@
 | Client        Ignia, LLC
 | Project       Topics Library
 \=============================================================================================================================*/
+using System.ComponentModel.DataAnnotations;
 using System.Reflection;
 using OnTopic.Attributes;
 
@@ -218,6 +219,20 @@ internal void SetValue(object target, object? value, bool allowConversion = fals
 
     }
 
+    /*==========================================================================================================================
+    | METHOD: VALIDATE
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Given a target DTO, will automatically identify any attributes that derive from <see cref="ValidationAttribute"/> and
+    ///   ensure that their conditions are satisfied.
+    /// </summary>
+    /// <param name="target">The target DTO to validate the current property on.</param>
+    internal void Validate(object target) {
+      foreach (ValidationAttribute validator in CustomAttributes.OfType<ValidationAttribute>()) {
+        validator.Validate(GetValue(target), Name);
+      }
+    }
+
     /*==========================================================================================================================
     | IS VALID?
     \-------------------------------------------------------------------------------------------------------------------------*/

OnTopic/Mapping/Internal/ItemConfiguration.cs

@@ -31,10 +31,6 @@ namespace OnTopic.Mapping.Internal {
   ///     then the <see cref="ITopicMappingService"/> will instead use the value defined by that attribute, thus allowing a
   ///     property on the DTO to be aliased to a different property or attribute name on the source <see cref="Topic"/>.
   ///   </para>
-  ///   <para>
-  ///     The <see cref="ItemConfiguration"/> works with both <see cref="ParameterInfo"/> and <see cref="PropertyInfo"/>
-  ///     instances, whereas the <see cref="PropertyConfiguration"/> works exclusively with <see cref="PropertyInfo"/> instances.
-  ///   </para>
   /// </remarks>
   internal class ItemConfiguration {
 
@@ -48,21 +44,18 @@ internal class ItemConfiguration {
     /// <param name="itemMetadata">
     ///   The <see cref="ItemMetadata"/> instance associated with this <see cref="ItemConfiguration"/>.
     /// </param>
-    /// <param name="name">The name of the <see cref="ParameterInfo"/> or <see cref="PropertyInfo"/>.</param>
-    /// <param name="attributePrefix">The prefix to apply to the attributes.</param>
-    internal ItemConfiguration(ItemMetadata itemMetadata, string name, string? attributePrefix = "") {
+    internal ItemConfiguration(ItemMetadata itemMetadata) {
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Set backing properties
       \-----------------------------------------------------------------------------------------------------------------------*/
-      Metadata                  = itemMetadata;
       CustomAttributes          = itemMetadata.CustomAttributes;
 
       /*------------------------------------------------------------------------------------------------------------------------
       | Set default values
       \-----------------------------------------------------------------------------------------------------------------------*/
-      AttributeKey              = attributePrefix + name;
-      AttributePrefix           = attributePrefix;
+      AttributeKey              = itemMetadata.Name;
+      AttributePrefix           = "";
       DefaultValue              = null;
       InheritValue              = false;
       CollectionKey             = AttributeKey;
@@ -79,9 +72,9 @@ internal ItemConfiguration(ItemMetadata itemMetadata, string name, string? attri
       GetAttributeValue<MapAsAttribute>(                        a => MapAs = a.Type);
       GetAttributeValue<DefaultValueAttribute>(                 a => DefaultValue = a.Value);
       GetAttributeValue<InheritAttribute>(                      a => InheritValue = true);
-      GetAttributeValue<AttributeKeyAttribute>(                 a => AttributeKey = attributePrefix + a.Key);
+      GetAttributeValue<AttributeKeyAttribute>(                 a => AttributeKey = a.Key);
       GetAttributeValue<MapToParentAttribute>(                  a => MapToParent = true);
-      GetAttributeValue<MapToParentAttribute>(                  a => AttributePrefix += (a.AttributePrefix?? name));
+      GetAttributeValue<MapToParentAttribute>(                  a => AttributePrefix += (a.AttributePrefix?? AttributeKey));
       GetAttributeValue<IncludeAttribute>(                      a => IncludeAssociations = a.Associations);
       GetAttributeValue<FlattenAttribute>(                      a => FlattenChildren = true);
       GetAttributeValue<MetadataAttribute>(                     a => MetadataKey = a.Key);
@@ -114,14 +107,6 @@ internal ItemConfiguration(ItemMetadata itemMetadata, string name, string? attri
 
     }
 
-    /*==========================================================================================================================
-    | PROPERTY: METADATA
-    \-------------------------------------------------------------------------------------------------------------------------*/
-    /// <summary>
-    ///   The <see cref="ItemMetadata"/> that the current <see cref="ItemConfiguration"/> is associated with.
-    /// </summary>
-    internal ItemMetadata Metadata { get; }
-
     /*==========================================================================================================================
     | PROPERTY: CUSTOM ATTRIBUTES
     \-------------------------------------------------------------------------------------------------------------------------*/
@@ -433,6 +418,21 @@ internal ItemConfiguration(ItemMetadata itemMetadata, string name, string? attri
     /// </remarks>
     internal Dictionary<string, string> AttributeFilters { get; }
 
+    /*==========================================================================================================================
+    | METHOD: GET COMPOSITE ATTRIBUTE KEY
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Retrieves the current <see cref="AttributeKey"/>, and, optionally, the supplied <paramref name="attributePrefix"/>.
+    /// </summary>
+    /// <param name="attributePrefix">
+    ///   The current mapping operation's attribute prefix to be prepended to the <see cref="AttributeKey"/>.
+    /// </param>
+    /// <returns>
+    ///   The composite attribute key, based on <see cref="AttributeKey"/> and, optionally, the supplied <paramref name="
+    ///   attributePrefix"/>.
+    /// </returns>
+    internal string GetCompositeAttributeKey(string? attributePrefix) => $"{attributePrefix}{AttributeKey}";
+
     /*==========================================================================================================================
     | METHOD: SATISFIES ATTRIBUTE FILTERS
     \-------------------------------------------------------------------------------------------------------------------------*/