EFCore 7 - SqlServer - DataAnnotation 'TypeName' and fluent API 'HasColumnType' is not being honored for aggregate type for which ToJson() is defined

[shvmgpt116]

I am using a sample application where I have defined [Column(TypeName = "VARCHAR(500)")] data annotation for entity property 'Contact'.

public class Author
        {
            public int Id { get; set; }
            [Column(TypeName = "VARCHAR(20)")]
            public string Name { get; set; }

            [Column(TypeName = "VARCHAR(500)")]
            public ContactDetails Contact { get; set; }
        }

EnsureCreated() generates following create table script where column Name honors data annotation but column Contact does not.

CREATE TABLE [Authors] (
          [Id] int NOT NULL IDENTITY,
          [Name] VARCHAR(20) NOT NULL,
          [Contact] nvarchar(max) NOT NULL,
          CONSTRAINT [PK_Authors] PRIMARY KEY ([Id])
      );

Using fluent API

modelBuilder.Entity<Author>().Property(p => p.Contact).HasColumnType("VARCHAR(500)");

instead of data annotation is giving following error -
Contact' cannot be used as a property on entity type 'Author' because it is configured as a navigation.

Here is my OnModelCreating() method-

protected override void OnModelCreating(ModelBuilder modelBuilder)
            {
                modelBuilder.Entity<Author>().OwnsOne(
                    author => author.Contact, ownedNavigationBuilder =>
                    {
                        ownedNavigationBuilder.ToJson();
                        ownedNavigationBuilder.OwnsOne(contactDetails => contactDetails.Address);
                    });
                modelBuilder.Entity<Author>().Property(p => p.Contact).HasColumnType("VARCHAR(500)");
            }

Please could someone clarify if default data types can be changed for JSON/Aggregate types or not?
If yes, what am I missing in my sample application.
If no, are there any future plans on supporting this?

Sample application

using System;
using Microsoft.EntityFrameworkCore;
using System.Linq;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace test
{
    class Program
    {
        public class ContactDetails
        {
            public Address Address { get; set; } = null!;
            public string? Phone { get; set; }
        }

        public class Address
        {
            public Address(string street, string city, string postcode, string country)
            {
                Street = street;
                City = city;
                Postcode = postcode;
                Country = country;
            }

            public string Street { get; set; }
            public string City { get; set; }
            public string Postcode { get; set; }
            public string Country { get; set; }
        }

        public class Author
        {
            public int Id { get; set; }
            [Column(TypeName = "VARCHAR(20)")]
            public string Name { get; set; }

            [Column(TypeName = "VARCHAR(500)")]
            public ContactDetails Contact { get; set; }
        }

        public class AuthorContext : DbContext
        {
            public DbSet<Author> Authors { get; set; }

            protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
            {
                optionsBuilder.UseSqlServer(@"<connection_string>").LogTo(Console.WriteLine);
            }

            protected override void OnModelCreating(ModelBuilder modelBuilder)
            {
                modelBuilder.Entity<Author>().OwnsOne(
                    author => author.Contact, ownedNavigationBuilder =>
                    {
                        ownedNavigationBuilder.ToJson();
                        ownedNavigationBuilder.OwnsOne(contactDetails => contactDetails.Address);
                    });
                //modelBuilder.Entity<Author>().Property(p => p.Contact).HasColumnType("VARCHAR(500)");
            }

            public static void Main()
            {
                using (var context = new AuthorContext())
                {
                    context.Database.EnsureDeleted();
                    context.Database.EnsureCreated();
                }
            }
        }
    }
}

Provider and version information

EF Core version: 7.0.0
Database provider: Microsoft.EntityFrameworkCore.SqlServer
Target framework: .NET 6.0
Operating system: Windows 10
IDE: Visual Studio 2022 17.2.6

[maumar]

dupe of #28452