Allow temporal period properties to be mapped to CLR properties

src/EFCore.SqlServer/Design/Internal/SqlServerAnnotationCodeGenerator.cs

@@ -338,7 +338,7 @@ public override IReadOnlyList<MethodCallCodeFragment> GenerateFluentApiCalls(
                 : null;
 
             // for the RevEng path, we avoid adding period properties to the entity
-            // because we don't want code for them to be generated - they need to be in shadow state
+            // because we don't want code for them to be generated - they are created as shadow properties
             // so if we don't find property on the entity, we know it's this scenario
             // and in that case period column name is actually the same as the period property name annotation
             // since in RevEng scenario there can't be custom column mapping

src/EFCore.SqlServer/EFCore.SqlServer.baseline.json

@@ -249,6 +249,12 @@
     {
       "Type": "class Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalTableBuilder<TOwnerEntity, TDependentEntity> : Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalTableBuilder where TOwnerEntity : class where TDependentEntity : class",
       "Methods": [
+        {
+          "Member": "virtual Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalPeriodPropertyBuilder Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalTableBuilder<TOwnerEntity, TDependentEntity>.HasPeriodEnd(System.Linq.Expressions.Expression<System.Func<TDependentEntity, System.DateTime>> propertyExpression);"
+        },
+        {
+          "Member": "virtual Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalPeriodPropertyBuilder Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalTableBuilder<TOwnerEntity, TDependentEntity>.HasPeriodStart(System.Linq.Expressions.Expression<System.Func<TDependentEntity, System.DateTime>> propertyExpression);"
+        },
         {
           "Member": "virtual Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalTableBuilder<TOwnerEntity, TDependentEntity> Microsoft.EntityFrameworkCore.Metadata.Builders.OwnedNavigationTemporalTableBuilder<TOwnerEntity, TDependentEntity>.UseHistoryTable(string name);"
         },
@@ -2630,7 +2636,7 @@
           "Member": "static System.Linq.IQueryable<Microsoft.EntityFrameworkCore.Query.FullTextSearchResult<TKey>> Microsoft.EntityFrameworkCore.SqlServerQueryableExtensions.FreeTextTable<T, TKey>(this Microsoft.EntityFrameworkCore.DbSet<T> source, string freeText, System.Linq.Expressions.Expression<System.Func<T, object>>? columnSelector = null, string? languageTerm = null, int? topN = null);"
         },
         {
-          "Member": "static System.Linq.IQueryable<Microsoft.EntityFrameworkCore.VectorSearchResult<T>> Microsoft.EntityFrameworkCore.SqlServerQueryableExtensions.VectorSearch<T, TVector>(this Microsoft.EntityFrameworkCore.DbSet<T> source, System.Linq.Expressions.Expression<System.Func<T, TVector>> vectorPropertySelector, TVector similarTo, string metric, int topN);",
+          "Member": "static System.Linq.IQueryable<Microsoft.EntityFrameworkCore.VectorSearchResult<T>> Microsoft.EntityFrameworkCore.SqlServerQueryableExtensions.VectorSearch<T, TVector>(this Microsoft.EntityFrameworkCore.DbSet<T> source, System.Linq.Expressions.Expression<System.Func<T, TVector>> vectorPropertySelector, TVector similarTo, string metric);",
           "Stage": "Experimental"
         }
       ]
@@ -3030,6 +3036,12 @@
     {
       "Type": "class Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalTableBuilder<TEntity> : Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalTableBuilder where TEntity : class",
       "Methods": [
+        {
+          "Member": "virtual Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalPeriodPropertyBuilder Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalTableBuilder<TEntity>.HasPeriodEnd(System.Linq.Expressions.Expression<System.Func<TEntity, System.DateTime>> propertyExpression);"
+        },
+        {
+          "Member": "virtual Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalPeriodPropertyBuilder Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalTableBuilder<TEntity>.HasPeriodStart(System.Linq.Expressions.Expression<System.Func<TEntity, System.DateTime>> propertyExpression);"
+        },
         {
           "Member": "virtual Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalTableBuilder<TEntity> Microsoft.EntityFrameworkCore.Metadata.Builders.TemporalTableBuilder<TEntity>.UseHistoryTable(string name);"
         },

src/EFCore.SqlServer/Infrastructure/Internal/SqlServerModelValidator.cs

@@ -449,13 +449,6 @@ private static void ValidateTemporalPeriodProperty(IEntityType temporalEntityTyp
                     temporalEntityType.DisplayName(), annotationPropertyName));
         }
 
-        if (!periodProperty.IsShadowProperty() && !temporalEntityType.IsPropertyBag)
-        {
-            throw new InvalidOperationException(
-                SqlServerStrings.TemporalPeriodPropertyMustBeInShadowState(
-                    temporalEntityType.DisplayName(), periodProperty.Name));
-        }
-
         if (periodProperty.IsNullable
             || periodProperty.ClrType != typeof(DateTime))
         {

src/EFCore.SqlServer/Metadata/Builders/OwnedNavigationTemporalTableBuilder``.cs

@@ -49,4 +49,36 @@ public OwnedNavigationTemporalTableBuilder(OwnedNavigationBuilder referenceOwner
     /// <returns>The same builder instance so that multiple calls can be chained.</returns>
     public new virtual OwnedNavigationTemporalTableBuilder<TOwnerEntity, TDependentEntity> UseHistoryTable(string name, string? schema)
         => (OwnedNavigationTemporalTableBuilder<TOwnerEntity, TDependentEntity>)base.UseHistoryTable(name, schema);
+
+    /// <summary>
+    ///     Returns an object that can be used to configure a period start property of the entity type mapped to a temporal table.
+    /// </summary>
+    /// <remarks>
+    ///     See <see href="https://aka.ms/efcore-docs-temporal">Using SQL Server temporal tables with EF Core</see>
+    ///     for more information.
+    /// </remarks>
+    /// <param name="propertyExpression">
+    ///     A lambda expression representing the property to be configured as the period start property
+    ///     (<c>entity => entity.PeriodStart</c>).
+    /// </param>
+    /// <returns>An object that can be used to configure the period start property.</returns>
+    public virtual OwnedNavigationTemporalPeriodPropertyBuilder HasPeriodStart(
+        Expression<Func<TDependentEntity, DateTime>> propertyExpression)
+        => HasPeriodStart(Check.NotNull(propertyExpression).GetMemberAccess().Name);
+
+    /// <summary>
+    ///     Returns an object that can be used to configure a period end property of the entity type mapped to a temporal table.
+    /// </summary>
+    /// <remarks>
+    ///     See <see href="https://aka.ms/efcore-docs-temporal">Using SQL Server temporal tables with EF Core</see>
+    ///     for more information.
+    /// </remarks>
+    /// <param name="propertyExpression">
+    ///     A lambda expression representing the property to be configured as the period end property
+    ///     (<c>entity => entity.PeriodEnd</c>).
+    /// </param>
+    /// <returns>An object that can be used to configure the period end property.</returns>
+    public virtual OwnedNavigationTemporalPeriodPropertyBuilder HasPeriodEnd(
+        Expression<Func<TDependentEntity, DateTime>> propertyExpression)
+        => HasPeriodEnd(Check.NotNull(propertyExpression).GetMemberAccess().Name);
 }

src/EFCore.SqlServer/Metadata/Builders/TemporalTableBuilder`.cs

@@ -47,4 +47,34 @@ public TemporalTableBuilder(EntityTypeBuilder entityTypeBuilder)
     /// <returns>The same builder instance so that multiple calls can be chained.</returns>
     public new virtual TemporalTableBuilder<TEntity> UseHistoryTable(string name, string? schema)
         => (TemporalTableBuilder<TEntity>)base.UseHistoryTable(name, schema);
+
+    /// <summary>
+    ///     Returns an object that can be used to configure a period start property of the entity type mapped to a temporal table.
+    /// </summary>
+    /// <remarks>
+    ///     See <see href="https://aka.ms/efcore-docs-temporal">Using SQL Server temporal tables with EF Core</see>
+    ///     for more information and examples.
+    /// </remarks>
+    /// <param name="propertyExpression">
+    ///     A lambda expression representing the property to be configured as the period start property
+    ///     (<c>blog => blog.PeriodStart</c>).
+    /// </param>
+    /// <returns>An object that can be used to configure the period start property.</returns>
+    public virtual TemporalPeriodPropertyBuilder HasPeriodStart(Expression<Func<TEntity, DateTime>> propertyExpression)
+        => HasPeriodStart(Check.NotNull(propertyExpression).GetMemberAccess().Name);
+
+    /// <summary>
+    ///     Returns an object that can be used to configure a period end property of the entity type mapped to a temporal table.
+    /// </summary>
+    /// <remarks>
+    ///     See <see href="https://aka.ms/efcore-docs-temporal">Using SQL Server temporal tables with EF Core</see>
+    ///     for more information and examples.
+    /// </remarks>
+    /// <param name="propertyExpression">
+    ///     A lambda expression representing the property to be configured as the period end property
+    ///     (<c>blog => blog.PeriodEnd</c>).
+    /// </param>
+    /// <returns>An object that can be used to configure the period end property.</returns>
+    public virtual TemporalPeriodPropertyBuilder HasPeriodEnd(Expression<Func<TEntity, DateTime>> propertyExpression)
+        => HasPeriodEnd(Check.NotNull(propertyExpression).GetMemberAccess().Name);
 }

src/EFCore.SqlServer/Properties/SqlServerStrings.resx

@@ -375,9 +375,6 @@
   <data name="TemporalPeriodPropertyCantHaveDefaultValue" xml:space="preserve">
     <value>Period property '{entityType}.{propertyName}' can't have a default value specified.</value>
   </data>
-  <data name="TemporalPeriodPropertyMustBeInShadowState" xml:space="preserve">
-    <value>Period property '{entityType}.{propertyName}' must be a shadow property.</value>
-  </data>
   <data name="TemporalPeriodPropertyMustBeMappedToDatetime2" xml:space="preserve">
     <value>Period property '{entityType}.{propertyName}' must be mapped to a column of type '{columnType}'.</value>
   </data>

test/EFCore.Design.Tests/Scaffolding/Internal/CSharpDbContextGeneratorTest.cs

@@ -1093,25 +1093,21 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
                 skipBuild: true);
 
         [ConditionalFact]
-        public async Task Temporal_table_works()
-            // Shadow properties. Issue #26007.
-            => Assert.Equal(
-                SqlServerStrings.TemporalPeriodPropertyMustBeInShadowState("Customer", "PeriodStart"),
-                (await Assert.ThrowsAsync<InvalidOperationException>(() =>
-                    TestAsync(
-                        modelBuilder => modelBuilder.Entity(
-                            "Customer", e =>
-                            {
-                                e.Property<int>("Id");
-                                e.Property<string>("Name");
-                                e.HasKey("Id");
-                                e.ToTable(tb => tb.IsTemporal());
-                            }),
-                        new ModelCodeGenerationOptions { UseDataAnnotations = false },
-                        code =>
-                        {
-                            AssertFileContents(
-                                $$"""
+        public Task Temporal_table_works()
+            => TestAsync(
+                modelBuilder => modelBuilder.Entity(
+                    "Customer", e =>
+                    {
+                        e.Property<int>("Id");
+                        e.Property<string>("Name");
+                        e.HasKey("Id");
+                        e.ToTable(tb => tb.IsTemporal());
+                    }),
+                new ModelCodeGenerationOptions { UseDataAnnotations = false },
+                code =>
+                {
+                    AssertFileContents(
+                        $$"""
 using System;
 using System.Collections.Generic;
 using Microsoft.EntityFrameworkCore;
@@ -1157,12 +1153,15 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
     partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
 }
 """,
-                                code.ContextFile);
-                        },
-                        model =>
-                        {
-                            // TODO
-                        }))).Message);
+                        code.ContextFile);
+                },
+                model =>
+                {
+                    var entityType = model.FindEntityType("TestNamespace.Customer")!;
+                    Assert.True(entityType.IsTemporal());
+                    Assert.Equal("PeriodStart", entityType.GetPeriodStartPropertyName());
+                    Assert.Equal("PeriodEnd", entityType.GetPeriodEndPropertyName());
+                });
 
         [ConditionalFact]
         public Task Sequences_work()