c# 自定义 IdentityUser 的 asp.net 外键违规

Question

我想使用带有附加属性的扩展 IdentityUser 类，

namespace SpaceShip.Model;

using Microsoft.AspNetCore.Identity;

public class UserEntity : IdentityUser
{
    // Additional properties 
}

在我的模型类中使用它的 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; }
}

我使用两个单独的数据库上下文来分隔关注点：

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
    }
}

当我尝试使用有效的 userId 创建新的 SpaceShip 时：

[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(); 
    }
}

我收到错误：

Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while saving the entity changes. See the inner exception for details.
---> Npgsql.PostgresException (0x80004005): 23503: insert or update on table "SpaceShips" violates foreign key constraint "FK_SpaceShips_UserEntity_UserId"

DETAIL: Key (UserId)=(b3a23cba-ad21-4e5a-9b25-8c5e139c67fe) is not present in table "UserEntity"

发生这种情况是因为约束：FK_SpaceShips_UserEntity_UserId 不引用“AspNetUsers”：

-- 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;

可以通过修改FK_SpaceShips_UserEntity_UserId引用“AspNetUsers”来暂时解决问题：

-- 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;

但它应该由实体框架配置，后续迁移可能会覆盖它。我不明白为什么外键约束默认不引用“AspNetUsers”。

Answer 1

仅使用一个数据库上下文解决了问题：

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

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

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

        // Map UserEntity to AspNetUsers table
        builder.Entity<UserEntity>().ToTable("AspNetUsers");

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

但是我仍然不清楚如何使用两个单独的上下文。