C# &ASP.NET Core：自定义 IdentityUser 的外键冲突

问：

我想使用具有附加属性的扩展类：IdentityUser

namespace SpaceShip.Model;

using Microsoft.AspNetCore.Identity;

public class UserEntity : IdentityUser
{
    // Additional properties 
}

在我的模型类中使用其 Id 作为外键：

public class SpaceShip
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string UserId { get; set; }

    // Navigation property
    public UserEntity User { get; set; }
}

我使用两个单独的 s 来区分关注点：DbContext

public class AppDbContext : DbContext
{
    public AppDbContext(DbContextOptions<AppDbContext> options) : base(options)
    {
    }

    public DbSet<SpaceShipModel> SpaceShips { get; set; } 

    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);

        // Configure the relationship between SpaceShip and AspNetUsers (UserEntity)
        builder.Entity<SpaceShipModel>()
            .HasOne<UserEntity>(s => s.User)
            .WithMany()
            .HasForeignKey(s => s.UserId)
            .IsRequired()
            .OnDelete(DeleteBehavior.Cascade); 
    }
} 

public class UserContext : IdentityDbContext<UserEntity>
{
    public UserContext(DbContextOptions<UserContext> options) : base(options)
    {
    }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);
        // Additional configuration
    }
}

当我尝试创建一个具有有效 ：SpaceShipuserId

[ApiController]
[Route("[controller]")]
public class SpaceShipController : ControllerBase
{
    private readonly SpaceShipService _spaceShipService;

    public SpaceShipController(SpaceShipService spaceShipService)
    {
        _spaceShipService = spaceShipService;
    }

    [HttpPost]
    public async Task<IActionResult> Create(string name, string userId)
    {
        await _spaceShipService.CreateSpaceShipAsync(name, userId);
        return Ok(); 
    }
}

我收到此错误：

Microsoft.EntityFrameworkCore.DbUpdateException：保存实体更改时出错。有关详细信息，请参阅内部异常。

Npgsql.PostgresException （0x80004005）： 23503：在表“SpaceShips”上插入或更新违反外键约束“FK_SpaceShips_UserEntity_UserId”

详细信息：表“UserEntity”中不存在密钥 （UserId）=（b3a23cba-ad21-4e5a-9b25-8c5e139c67fe）

发生这种情况是因为约束不是指：FK_SpaceShips_UserEntity_UserIdAspNetUsers

-- Constraint: FK_SpaceShips_UserEntity_UserId

-- ALTER TABLE IF EXISTS public."SpaceShips" DROP CONSTRAINT IF EXISTS "FK_SpaceShips_UserEntity_UserId";

ALTER TABLE IF EXISTS public."SpaceShips"
    ADD CONSTRAINT "FK_SpaceShips_UserEntity_UserId" 
        FOREIGN KEY ("UserId")
        REFERENCES public."UserEntity" ("Id") MATCH SIMPLE
            ON UPDATE NO ACTION
            ON DELETE CASCADE;

问题可以通过修改来暂时解决，参考：FK_SpaceShips_UserEntity_UserIdAspNetUsers

-- Constraint: FK_SpaceShips_UserEntity_UserId

-- ALTER TABLE IF EXISTS public."SpaceShips" DROP CONSTRAINT IF EXISTS "FK_SpaceShips_UserEntity_UserId";

ALTER TABLE IF EXISTS public."SpaceShips"
    ADD CONSTRAINT "FK_SpaceShips_UserEntity_UserId" 
        FOREIGN KEY ("UserId")
        REFERENCES public."AspNetUsers" ("Id") MATCH SIMPLE
            ON UPDATE NO ACTION
            ON DELETE CASCADE;

但它应由实体框架配置，后续迁移可能会覆盖它。我不明白为什么默认情况下不引用外键约束。AspNetUsers