Metadata work for json.

src/EFCore.Relational/Design/AnnotationCodeGenerator.cs

@@ -35,7 +35,8 @@ public class AnnotationCodeGenerator : IAnnotationCodeGenerator
         RelationalAnnotationNames.InsertStoredProcedure,
         RelationalAnnotationNames.UpdateStoredProcedure,
         RelationalAnnotationNames.MappingFragments,
-        RelationalAnnotationNames.RelationalOverrides
+        RelationalAnnotationNames.RelationalOverrides,
+        RelationalAnnotationNames.JsonColumnTypeMapping
     };
 
     #region MethodInfos
@@ -136,6 +137,10 @@ private static readonly MethodInfo IndexHasFilterNameMethodInfo
         = typeof(RelationalIndexBuilderExtensions).GetRuntimeMethod(
             nameof(RelationalIndexBuilderExtensions.HasFilter), new[] { typeof(IndexBuilder), typeof(string) })!;
 
+    private static readonly MethodInfo ToJsonMethodInfo
+        = typeof(RelationalOwnedNavigationBuilderExtensions).GetRuntimeMethod(
+            nameof(RelationalOwnedNavigationBuilderExtensions.ToJson), new[] { typeof(OwnedNavigationBuilder), typeof(string) })!;
+
     #endregion MethodInfos
 
     /// <summary>
@@ -303,6 +308,19 @@ public virtual IReadOnlyList<MethodCallCodeFragment> GenerateFluentApiCalls(
             }
         }
 
+        if (annotations.TryGetValue(RelationalAnnotationNames.JsonColumnName, out var jsonColumnNameAnnotation)
+            && jsonColumnNameAnnotation != null && jsonColumnNameAnnotation.Value is string jsonColumnName
+            && entityType.IsOwned())
+        {
+            methodCallCodeFragments.Add(
+                new MethodCallCodeFragment(
+                    ToJsonMethodInfo,
+                    jsonColumnName));
+
+            annotations.Remove(RelationalAnnotationNames.JsonColumnName);
+            annotations.Remove(RelationalAnnotationNames.JsonColumnTypeMapping);
+        }
+
         methodCallCodeFragments.AddRange(GenerateFluentApiCallsHelper(entityType, annotations, GenerateFluentApi));
 
         return methodCallCodeFragments;

src/EFCore.Relational/Extensions/Internal/RelationalPropertyInternalExtensions.cs

@@ -0,0 +1,28 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.EntityFrameworkCore.Metadata.Internal
+{
+    /// <summary>
+    ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
+    ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
+    ///     any release. You should only use it directly in your code with extreme caution and knowing that
+    ///     doing so can result in application failures when updating to a new Entity Framework Core release.
+    /// </summary>
+    public static class RelationalPropertyInternalExtensions
+    {
+        /// <summary>
+        ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
+        ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
+        ///     any release. You should only use it directly in your code with extreme caution and knowing that
+        ///     doing so can result in application failures when updating to a new Entity Framework Core release.
+        /// </summary>
+        public static bool IsOrdinalKeyProperty(this IReadOnlyProperty property)
+            => property.FindContainingPrimaryKey() is IReadOnlyKey key
+                && key.Properties.Count > 1
+                && !property.IsForeignKey()
+                && property.IsShadowProperty()
+                && property.ClrType == typeof(int)
+                && property.GetJsonPropertyName() == null;
+    }
+}

src/EFCore.Relational/Extensions/RelationalEntityTypeExtensions.cs

@@ -62,7 +62,7 @@ public static class RelationalEntityTypeExtensions
 
         var ownership = entityType.FindOwnership();
         if (ownership != null
-            && ownership.IsUnique)
+            && (ownership.IsUnique || entityType.IsMappedToJson()))
         {
             return ownership.PrincipalEntityType.GetTableName();
         }
@@ -316,7 +316,7 @@ public static IEnumerable<ITableMapping> GetTableMappings(this IEntityType entit
 
         var ownership = entityType.FindOwnership();
         return ownership != null
-            && ownership.IsUnique
+            && (ownership.IsUnique || entityType.IsMappedToJson())
                 ? ownership.PrincipalEntityType.GetViewName()
                 : null;
     }
@@ -1385,7 +1385,7 @@ public static IEnumerable<IReadOnlyForeignKey> FindRowInternalForeignKeys(
         StoreObjectIdentifier storeObject)
     {
         var primaryKey = entityType.FindPrimaryKey();
-        if (primaryKey == null)
+        if (primaryKey == null || entityType.IsMappedToJson())
         {
             yield break;
         }
@@ -1855,4 +1855,96 @@ public static IEnumerable<ITrigger> GetDeclaredTriggers(this IEntityType entityT
         => Trigger.GetDeclaredTriggers(entityType).Cast<ITrigger>();
 
     #endregion Trigger
+
+    #region Json
+
+    /// <summary>
+    ///     Gets a value indicating whether the specified entity is mapped to a JSON column.
+    /// </summary>
+    /// <param name="entityType">The entity type.</param>
+    /// <returns>A value indicating whether the associated entity type is mapped to a JSON column.</returns>
+    public static bool IsMappedToJson(this IReadOnlyEntityType entityType)
+        => !string.IsNullOrEmpty(entityType.GetJsonColumnName());
+
+    /// <summary>
+    ///     Sets the name of the JSON column to which the entity type is mapped.
+    /// </summary>
+    /// <param name="entityType">The entity type to set the JSON column name for.</param>
+    /// <param name="columnName">The name to set.</param>
+    public static void SetJsonColumnName(this IMutableEntityType entityType, string? columnName)
+        => entityType.SetOrRemoveAnnotation(RelationalAnnotationNames.JsonColumnName, columnName);
+
+    /// <summary>
+    ///     Sets the name of the JSON column to which the entity type is mapped.
+    /// </summary>
+    /// <param name="entityType">The entity type to set the JSON column name for.</param>
+    /// <param name="columnName">The name to set.</param>
+    /// <param name="fromDataAnnotation">Indicates whether the configuration was specified using a data annotation.</param>
+    /// <returns>The configured value.</returns>
+    public static string? SetJsonColumnName(
+        this IConventionEntityType entityType,
+        string? columnName,
+        bool fromDataAnnotation = false)
+        => (string?)entityType.SetAnnotation(RelationalAnnotationNames.JsonColumnName, columnName, fromDataAnnotation)?.Value;
+
+    /// <summary>
+    ///     Gets the <see cref="ConfigurationSource" /> for the JSON column name.
+    /// </summary>
+    /// <param name="entityType">The entity type to set the JSON column name for.</param>
+    /// <returns>The <see cref="ConfigurationSource" /> for the JSON column name.</returns>
+    public static ConfigurationSource? GetJsonColumnNameConfigurationSource(this IConventionEntityType entityType)
+        => entityType.FindAnnotation(RelationalAnnotationNames.JsonColumnName)
+            ?.GetConfigurationSource();
+
+    /// <summary>
+    ///     Gets the JSON column name to which the entity type is mapped.
+    /// </summary>
+    /// <param name="entityType">The entity type to get the JSON column name for.</param>
+    /// <returns>The JSON column name to which the entity type is mapped.</returns>
+    public static string? GetJsonColumnName(this IReadOnlyEntityType entityType)
+        => entityType.FindAnnotation(RelationalAnnotationNames.JsonColumnName)?.Value is string jsonColumnName
+            ? jsonColumnName
+            : (entityType.FindOwnership()?.PrincipalEntityType.GetJsonColumnName());
+
+    /// <summary>
+    ///     Sets the type mapping for the JSON column to which the entity type is mapped.
+    /// </summary>
+    /// <param name="entityType">The entity type to set the JSON column type mapping for.</param>
+    /// <param name="typeMapping">The type mapping to set.</param>
+    public static void SetJsonColumnTypeMapping(this IMutableEntityType entityType, RelationalTypeMapping typeMapping)
+        => entityType.SetOrRemoveAnnotation(RelationalAnnotationNames.JsonColumnTypeMapping, typeMapping);
+
+    /// <summary>
+    ///     Sets the type mapping for the JSON column to which the entity type is mapped.
+    /// </summary>
+    /// <param name="entityType">The entity type to set the JSON column type mapping for.</param>
+    /// <param name="typeMapping">The type mapping to set.</param>
+    /// <param name="fromDataAnnotation">Indicates whether the configuration was specified using a data annotation.</param>
+    /// <returns>The configured value.</returns>
+    public static RelationalTypeMapping? SetJsonColumnTypeMapping(
+        this IConventionEntityType entityType,
+        RelationalTypeMapping? typeMapping,
+        bool fromDataAnnotation = false)
+        => (RelationalTypeMapping?)entityType.SetAnnotation(RelationalAnnotationNames.JsonColumnTypeMapping, typeMapping, fromDataAnnotation)?.Value;
+
+    /// <summary>
+    ///     Gets the <see cref="ConfigurationSource" /> for the JSON column type mapping.
+    /// </summary>
+    /// <param name="entityType">The entity type to set the JSON column type mapping for.</param>
+    /// <returns>The <see cref="ConfigurationSource" /> for the JSON column type mapping.</returns>
+    public static ConfigurationSource? GetJsonColumnTypeMappingConfigurationSource(this IConventionEntityType entityType)
+        => entityType.FindAnnotation(RelationalAnnotationNames.JsonColumnTypeMapping)
+            ?.GetConfigurationSource();
+
+    /// <summary>
+    ///     Gets the JSON column type mapping to which the entity type is mapped.
+    /// </summary>
+    /// <param name="entityType">The entity type to get the JSON column type mapping for.</param>
+    /// <returns>The JSON column type mapping to which the entity type is mapped.</returns>
+    public static RelationalTypeMapping? GetJsonColumnTypeMapping(this IReadOnlyEntityType entityType)
+        => entityType.FindAnnotation(RelationalAnnotationNames.JsonColumnTypeMapping)?.Value is RelationalTypeMapping jsonColumnTypeMapping
+            ? jsonColumnTypeMapping
+            : (entityType.FindOwnership()?.PrincipalEntityType.GetJsonColumnTypeMapping());
+
+    #endregion
 }

src/EFCore.Relational/Extensions/RelationalNavigationBuilderExtensions.cs

@@ -0,0 +1,52 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.EntityFrameworkCore;
+
+/// <summary>
+///     Relational database specific extension methods for <see cref="NavigationBuilder" />.
+/// </summary>
+/// <remarks>
+///     See <see href="https://aka.ms/efcore-docs-modeling">Modeling entity types and relationships</see> for more information and examples.
+/// </remarks>
+public static class RelationalNavigationBuilderExtensions
+{
+    /// <summary>
+    ///     Configures the navigation of an entity mapped to a JSON column, mapping the navigation to a specific JSON property,
+    ///     rather than using the navigation name.
+    /// </summary>
+    /// <param name="navigationBuilder">The builder for the navigation being configured.</param>
+    /// <param name="name">JSON property name to be used.</param>
+    /// <param name="fromDataAnnotation">Indicates whether the configuration was specified using a data annotation.</param>
+    /// <returns>
+    ///     The same builder instance if the configuration was applied,
+    ///     <see langword="null" /> otherwise.
+    /// </returns>
+    public static IConventionNavigationBuilder? HasJsonPropertyName(
+        this IConventionNavigationBuilder navigationBuilder,
+        string? name,
+        bool fromDataAnnotation = false)
+    {
+        if (!navigationBuilder.CanSetJsonPropertyName(name, fromDataAnnotation))
+        {
+            return null;
+        }
+
+        navigationBuilder.Metadata.SetJsonPropertyName(name, fromDataAnnotation);
+
+        return navigationBuilder;
+    }
+
+    /// <summary>
+    ///     Returns a value indicating whether the given value can be used as a JSON property name for a given navigation.
+    /// </summary>
+    /// <param name="navigationBuilder">The builder for the navigation being configured.</param>
+    /// <param name="name">JSON property name to be used.</param>
+    /// <param name="fromDataAnnotation">Indicates whether the configuration was specified using a data annotation.</param>
+    /// <returns><see langword="true" /> if the given value can be set as JSON property name for this navigation.</returns>
+    public static bool CanSetJsonPropertyName(
+        this IConventionNavigationBuilder navigationBuilder,
+        string? name,
+        bool fromDataAnnotation = false)
+        => navigationBuilder.CanSetAnnotation(RelationalAnnotationNames.JsonPropertyName, name, fromDataAnnotation);
+}

src/EFCore.Relational/Extensions/RelationalNavigationExtensions.cs

@@ -0,0 +1,66 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.EntityFrameworkCore;
+
+/// <summary>
+///     Navigation extension methods for relational database metadata.
+/// </summary>
+/// <remarks>
+///     See <see href="https://aka.ms/efcore-docs-modeling">Modeling entity types and relationships</see> for more information and examples.
+/// </remarks>
+public static class RelationalNavigationExtensions
+{
+    /// <summary>
+    ///     Gets the value of JSON property name used for the given navigation of an entity mapped to a JSON column.
+    /// </summary>
+    /// <remarks>
+    ///     Unless configured explicitly, navigation name is used.
+    /// </remarks>
+    /// <param name="navigation">The navigation.</param>
+    /// <returns>
+    ///     The value for the JSON property used to store the value of this navigation.
+    ///     <see langword="null" /> is returned for navigations of entities that are not mapped to a JSON column.
+    /// </returns>
+    public static string? GetJsonPropertyName(this IReadOnlyNavigationBase navigation)
+        => (string?)navigation.FindAnnotation(RelationalAnnotationNames.JsonPropertyName)?.Value
+            ?? (!navigation.DeclaringEntityType.IsMappedToJson() ? null : navigation.Name);
+
+    /// <summary>
+    ///     Sets the value of JSON property name used for the given navigation of an entity mapped to a JSON column.
+    /// </summary>
+    /// <param name="navigation">The navigation.</param>
+    /// <param name="name">The name to be used.</param>
+    public static void SetJsonPropertyName(this IMutableNavigationBase navigation, string? name)
+        => navigation.SetOrRemoveAnnotation(
+            RelationalAnnotationNames.JsonPropertyName,
+            Check.NullButNotEmpty(name, nameof(name)));
+
+    /// <summary>
+    ///     Sets the value of JSON property name used for the given navigation of an entity mapped to a JSON column.
+    /// </summary>
+    /// <param name="navigation">The navigation.</param>
+    /// <param name="name">The name to be used.</param>
+    /// <param name="fromDataAnnotation">Indicates whether the configuration was specified using a data annotation.</param>
+    /// <returns>The configured value.</returns>
+    public static string? SetJsonPropertyName(
+        this IConventionNavigationBase navigation,
+        string? name,
+        bool fromDataAnnotation = false)
+    {
+        navigation.SetOrRemoveAnnotation(
+            RelationalAnnotationNames.JsonPropertyName,
+            Check.NullButNotEmpty(name, nameof(name)),
+            fromDataAnnotation);
+
+        return name;
+    }
+
+    /// <summary>
+    ///     Gets the <see cref="ConfigurationSource" /> for the JSON property name for a given navigation.
+    /// </summary>
+    /// <param name="navigation">The navigation.</param>
+    /// <returns>The <see cref="ConfigurationSource" /> for the JSON property name for a given navigation.</returns>
+    public static ConfigurationSource? GetJsonPropertyNameConfigurationSource(this IConventionNavigationBase navigation)
+        => navigation.FindAnnotation(RelationalAnnotationNames.JsonPropertyName)?.GetConfigurationSource();
+}