Merge branch 'feature/Skip-Orphaned-LastModified' into develop

Remove byline and dateline if no other attributes are updated (#20)

Introduces centralized logic—via a new `AttributeValueCollection.IsDirty(excludeLastModified)` overload—for detecting if any attributes on a topic have actually been modified outside of the automatically-generated `LastModified` attributes (e.g., `LastModified`, `LastModifiedBy`). If not, this can be used by e.g. `ITopicRepository.Save()` to skip saving attribute values, and thus preventing extraneous bylines and datelines from being persisted when no other changes have been committed.

Includes:
- Skip indexed attributes if only the dateline, byline have changed (dedf9fc)
- Introduced new `IsDirty()` overloads for `AttributeValueCollection` (d3b49ff)

Author: JeremyCaney

OnTopic.Data.Sql/SqlTopicRepository.cs

@@ -289,14 +289,22 @@ public override int Save([NotNull]Topic topic, bool isRecursive = false, bool is
       /*------------------------------------------------------------------------------------------------------------------------
       | Add indexed attributes that are dirty
       \-----------------------------------------------------------------------------------------------------------------------*/
-      foreach (var attributeValue in GetAttributes(topic, false, true)) {
+      //Exclude indexed attributes if the only dirty attributes are `LastModified` and/or `LastModifiedBy`, as these are
+      //automatically generated and don't represent genuine changes to the topic.
+      if (topic.Attributes.IsDirty(true)) {
 
-        var record              = attributes.NewRow();
-        record["AttributeKey"]  = attributeValue.Key;
-        record["AttributeValue"]= attributeValue.Value;
-        attributeValue.IsDirty  = false;
+        var indexedAttributes   = GetAttributes(topic, false, true);
 
-        attributes.Rows.Add(record);
+        foreach (var attributeValue in indexedAttributes) {
+
+          var record              = attributes.NewRow();
+          record["AttributeKey"]  = attributeValue.Key;
+          record["AttributeValue"]= attributeValue.Value;
+          attributeValue.IsDirty  = false;
+
+          attributes.Rows.Add(record);
+
+        }
 
       }
 

OnTopic.Tests/AttributeValueCollectionTest.cs

@@ -8,6 +8,7 @@
 using OnTopic.Attributes;
 using OnTopic.Collections;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System.Globalization;
 
 namespace OnTopic.Tests {
 
@@ -251,6 +252,65 @@ public void SetValue_ValueUnchanged_IsNotDirty() {
 
     }
 
+    /*==========================================================================================================================
+    | TEST: IS DIRTY: DIRTY VALUES: RETURNS TRUE
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Populates the <see cref="AttributeValueCollection"/> with a <see cref="AttributeValue"/> that is marked as <see
+    ///   cref="AttributeValue.IsDirty"/>. Confirms that <see cref="AttributeValueCollection.IsDirty(Boolean)"/> returns
+    ///   <c>true</c>/
+    /// </summary>
+    [TestMethod]
+    public void IsDirty_DirtyValues_ReturnsTrue() {
+
+      var topic = TopicFactory.Create("Test", "Container");
+
+      topic.Attributes.SetValue("Foo", "Bar");
+
+      Assert.IsTrue(topic.Attributes.IsDirty());
+
+    }
+
+    /*==========================================================================================================================
+    | TEST: IS DIRTY: NO DIRTY VALUES: RETURNS FALSE
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Populates the <see cref="AttributeValueCollection"/> with a <see cref="AttributeValue"/> that is <i>not</i> marked as
+    ///   <see cref="AttributeValue.IsDirty"/>. Confirms that <see cref="AttributeValueCollection.IsDirty(Boolean)"/> returns
+    ///   <c>false</c>/
+    /// </summary>
+    [TestMethod]
+    public void IsDirty_NoDirtyValues_ReturnsFalse() {
+
+      var topic = TopicFactory.Create("Test", "Container", 1);
+
+      topic.Attributes.SetValue("Foo", "Bar", false);
+
+      Assert.IsFalse(topic.Attributes.IsDirty());
+
+    }
+
+    /*==========================================================================================================================
+    | TEST: IS DIRTY: EXCLUDE LAST MODIFIED: RETURNS FALSE
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Populates the <see cref="AttributeValueCollection"/> with a <see cref="AttributeValue"/> that is <i>not</i> marked as
+    ///   <see cref="AttributeValue.IsDirty"/> as well as a <c>LastModified</c> <see cref="AttributeValue"/> that is. Confirms
+    ///   that <see cref="AttributeValueCollection.IsDirty(Boolean)"/> returns <c>false</c>.
+    /// </summary>
+    [TestMethod]
+    public void IsDirty_ExcludeLastModified_ReturnsFalse() {
+
+      var topic = TopicFactory.Create("Test", "Container", 1);
+
+      topic.Attributes.SetValue("Foo", "Bar", false);
+      topic.Attributes.SetValue("LastModified", DateTime.Now.ToString(CultureInfo.InvariantCulture));
+      topic.Attributes.SetValue("LastModifiedBy", "System");
+
+      Assert.IsFalse(topic.Attributes.IsDirty(true));
+
+    }
+
     /*==========================================================================================================================
     | TEST: SET VALUE: INVALID VALUE: THROWS EXCEPTION
     \-------------------------------------------------------------------------------------------------------------------------*/

OnTopic/Collections/AttributeValueCollection.cs

@@ -6,6 +6,7 @@
 using System;
 using System.Collections.ObjectModel;
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 using OnTopic.Attributes;
 using OnTopic.Internal.Diagnostics;
 using OnTopic.Internal.Reflection;
@@ -54,14 +55,37 @@ internal AttributeValueCollection(Topic parentTopic) : base(StringComparer.Invar
     /*==========================================================================================================================
     | METHOD: IS DIRTY
     \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Determine if <i>any</i> attributes in the <see cref="AttributeValueCollection"/> are dirty.
+    /// </summary>
+    /// <remarks>
+    ///   This method is intended primarily for data storage providers, such as
+    ///   <see cref="Repositories.ITopicRepository"/>, which may need to determine if any attributes are dirty prior to saving
+    ///   them to the data storage medium. Be aware that this does <i>not</i> track any <see cref="AttributeValue"/>s that may
+    ///   have been <i>deleted</i>, nor whether any <see cref="Topic.Relationships"/> have been modified; as such, it may still
+    ///   be necessary to persist changes to the storage medium.
+    /// </remarks>
+    /// <param name="excludeLastModified">
+    ///   Optionally excludes <see cref="AttributeValue"/>s whose keys start with <c>LastModified</c>. This is useful for
+    ///   excluding the byline (<c>LastModifiedBy</c>) and dateline (<c>LastModified</c>) since these values are automatically
+    ///   generated by e.g. the OnTopic Editor and, thus, may be irrelevant updates if no other attribute values have changed.
+    /// </param>
+    /// <returns>True if the attribute value is marked as dirty; otherwise false.</returns>
+    public bool IsDirty(bool excludeLastModified = false)
+      => Items.Any(a =>
+        a.IsDirty &&
+        (!excludeLastModified || !a.Key.StartsWith("LastModified", StringComparison.InvariantCultureIgnoreCase))
+      );
+
     /// <summary>
     ///   Determine if a given attribute is marked as dirty. Will return false if the attribute key cannot be found.
     /// </summary>
     /// <remarks>
     ///   This method is intended primarily for data storage providers, such as
     ///   <see cref="OnTopic.Repositories.ITopicRepository"/>, which may need to determine if a specific attribute key is
-    ///   dirty prior to saving it to the data storage medium. Because isDirty is a state of the current attribute value, it
-    ///   does not support inheritFromParent or inheritFromDerived (which otherwise default to true).
+    ///   dirty prior to saving it to the data storage medium. Because <c>IsDirty</c> is a state of the current <see
+    ///   cref="AttributeValue"/>, it does not support <c>inheritFromParent</c> or <c>inheritFromDerived</c> (which otherwise
+    ///   default to <c>true</c>).
     /// </remarks>
     /// <param name="name">The string identifier for the <see cref="AttributeValue"/>.</param>
     /// <returns>True if the attribute value is marked as dirty; otherwise false.</returns>