Hierarchical property name support in SqlColumn class

Author: ckadluba

src/Serilog.Sinks.MSSqlServer/Sinks/MSSqlServer/SqlColumn.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Data;
 using static System.FormattableString;
 
@@ -12,6 +13,7 @@ public class SqlColumn
         private SqlDbType _dataType = SqlDbType.VarChar; // backwards-compatibility default
         private string _columnName = string.Empty;
         private string _propertyName;
+        private List<string> _propertyNameHierarchy = new List<string>();
 
         /// <summary>
         /// Default constructor.
@@ -104,13 +106,30 @@ public SqlDbType DataType
         public string PropertyName
         {
             get => _propertyName ?? ColumnName;
-            set => _propertyName = value;
+            set
+            {
+                _propertyName = value;
+                ParseHierarchicalPropertyName(value);
+            }
         }
 
+        /// <summary>
+        /// List of the hierachical parts of a property name and all sub properties (e.g. Property.Settings.EventName)
+        /// </summary>
+        internal IReadOnlyList<string> PropertyNameHierarchy
+            => _propertyNameHierarchy;
+
+        /// <summary>
+        /// True if property name is hierarchical (e.g. Property.Settings.EventName)
+        /// </summary>
+        internal bool HasHierarchicalPropertyName
+            => _propertyNameHierarchy.Count > 1;
+
         // Set by the constructors of the Standard Column classes that inherit from this;
         // allows Standard Columns and user-defined columns to coexist but remain identifiable
         // and allows casting back to the Standard Column without a lot of switch gymnastics.
         internal StandardColumn? StandardColumnIdentifier { get; set; }
+
         internal Type StandardColumnType { get; set; }
 
         /// <summary>
@@ -150,5 +169,10 @@ internal void SetDataTypeFromConfigString(string requestedSqlType)
 
             DataType = sqlType;
         }
+
+        private void ParseHierarchicalPropertyName(string propertyName)
+        {
+            _propertyNameHierarchy.AddRange(propertyName.Split('.'));
+        }
     }
 }

test/Serilog.Sinks.MSSqlServer.Tests/Sinks/MSSqlServer/SqlServerColumnTests.cs

@@ -1,6 +1,7 @@
 using System.Data;
 using Serilog.Sinks.MSSqlServer.Tests.TestUtils;
 using Xunit;
+using static System.FormattableString;
 
 namespace Serilog.Sinks.MSSqlServer.Tests
 {
@@ -32,6 +33,33 @@ public void StoresPropertyName()
 
             // Assert
             Assert.Equal(propertyName, sut.PropertyName);
+            Assert.Equal(1, sut.PropertyNameHierarchy.Count);
+            Assert.Equal(propertyName, sut.PropertyNameHierarchy[0]);
+            Assert.False(sut.HasHierarchicalPropertyName);
+        }
+
+        [Fact]
+        public void StoresHierachicalPropertyName()
+        {
+            // Arrange
+            const string propertyName1 = "TestPropertyName";
+            const string propertyName2 = "SubPropertyName";
+            const string propertyName3 = "SubSubPropertyName";
+            var propertyName = Invariant($"{propertyName1}.{propertyName2}.{propertyName3}");
+
+            // Act
+            var sut = new SqlColumn("TestColumnName", SqlDbType.Int)
+            {
+                PropertyName = propertyName
+            };
+
+            // Assert
+            Assert.Equal(propertyName, sut.PropertyName);
+            Assert.Equal(3, sut.PropertyNameHierarchy.Count);
+            Assert.Equal(propertyName1, sut.PropertyNameHierarchy[0]);
+            Assert.Equal(propertyName2, sut.PropertyNameHierarchy[1]);
+            Assert.Equal(propertyName3, sut.PropertyNameHierarchy[2]);
+            Assert.True(sut.HasHierarchicalPropertyName);
         }
     }
 }