如何在设计时将接口注入到 DbContext 的构造函数中 ASP.NET Core Identity

Question

我需要在设计时将

ICurrentTenantRepository

接口的实例传递到我的

AppDbContext

类的构造函数中，但我不知道该怎么做。我对这个主题做了很多研究，但没有找到任何对我有帮助的东西......

如果我在设计时不创建它，它可以正常工作，但如果我在设计时创建它，我需要创建一个新的

AppDbContext

实例，此时我不知道该怎么做。

有人知道如何帮助我吗？

谢谢！

public sealed class AppDbContext : DbContext, IUnitOfWork
{       
    private readonly ICurrentTenantRepository _currentTenantRepository;
    public string CurrentTenantId { get; set; }
    public string CurrentTenantConnectionString { get; set; }

    public AppDbContext(DbContextOptions<AppDbContext> options, ICurrentTenantRepository currentTenantRepository) : base(options)
    {
        _currentTenantRepository = currentTenantRepository;

        if (_currentTenantRepository is not null)
        {
            CurrentTenantId = _currentTenantRepository.TenantId;
            CurrentTenantConnectionString = _currentTenantRepository.ConnectionString;
        }

        ChangeTracker.QueryTrackingBehavior = QueryTrackingBehavior.NoTracking;
        ChangeTracker.AutoDetectChangesEnabled = false;
    }       
}

public  class AppDbContextFactory : IDesignTimeDbContextFactory<AppDbContext>
{
    public AppDbContext CreateDbContext(string[] args) // neccessary for EF migration designer to run on this context
    {
        var builder = WebApplication.CreateBuilder(args);
        var optionsBuilder = new DbContextOptionsBuilder<AppDbContext>();
        optionsBuilder.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection"));

        return new AppDbContext(optionsBuilder.Options);
    }
}

 public interface ICurrentTenantRepository
 {
     string? ConnectionString { get; set; }
     string? TenantId { get; set; }
     public Task<bool> SetTenant(string tenant);
 }

 public class CurrentTenantRepository : ICurrentTenantRepository
{
    private readonly TenantDbContext _context;
    public string? ConnectionString { get; set; }
    public string? TenantId { get; set; }

    public CurrentTenantRepository(TenantDbContext context)
    {
        _context = context;
    }

    public async Task<bool> SetTenant(string tenant)
    {
        var tenantInfo = await _context.Tenants.Where(x => x.Id == tenant).FirstOrDefaultAsync(); // check if tenant exists
        if (tenantInfo != null)
        {
            TenantId = tenant;
            ConnectionString = tenantInfo.ConnectionString; // optional connection string per tenant (can be null to use default database)
            return true;
        }
        else
        {
            throw new Exception("Tenant invalid");
        }
    }
}

Answer 1

谢谢@Tanveer Badar

解决方案：

返回 new AppDbContext(optionsBuilder.Options, new CurrentTenantRepository(new TenantDbContext(new DbContextOptions())));