闲话 Asp.Net Core 数据校验（三）EF Core 集成 FluentValidation 校验数据例子

// LoginRequest 类只是一个普通的C#类，
// 没有标注任何的Attribute或者实现任何的接口，
// 它的唯一责任就是传递数据
public record LoginRequest(string Email, string Password, string PasswordConfirm);

{
  "Logging": {
  "LogLevel": {
    "Default": "Information",
    "Microsoft.AspNetCore": "Warning"
  }
  },
  "AllowedHosts": "*",
  "ConnectionStrings": {
  "Default": "Server=(localdb)\\mssqllocaldb;Database=IdentityTestDB;Trusted_Connection=True;MultipleActiveResultSets=true"
  }
}

using Microsoft.AspNetCore.Identity;
public class User : IdentityUser<long>
{
  public DateTime CreationTime { get; set; }
  public string? NickName { get; set; }
}
public class Role : IdentityRole<long>
{
}

using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore;
public class TestDbContext : IdentityDbContext<User, Role, long>
{
  public TestDbContext(DbContextOptions<TestDbContext> options)
    : base(options)
  {
  }
  protected override void OnModelCreating(ModelBuilder modelBuilder)
  {
    base.OnModelCreating(modelBuilder);
    modelBuilder.ApplyConfigurationsFromAssembly(this.GetType().Assembly);
  }
}

using FluentValidation;
using FluentValidation.AspNetCore;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using System.Reflection;
var builder = WebApplication.CreateBuilder(args);
// Add services to the container.
builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
// 注册标识框架相关的服务，并配置相关选项
IServiceCollection services = builder.Services;
services.AddDbContext<TestDbContext>(opt =>
{
  string connStr = builder.Configuration.GetConnectionString("Default")!;
  opt.UseSqlServer(connStr);
});
services.AddDataProtection();
services.AddIdentityCore<User>(options =>
{
  options.Password.RequireDigit = false;
  options.Password.RequireLowercase = false;
  options.Password.RequireNonAlphanumeric = false;
  options.Password.RequireUppercase = false;
  options.Password.RequiredLength = 6;
  options.Tokens.PasswordResetTokenProvider = TokenOptions.DefaultEmailProvider;
  options.Tokens.EmailConfirmationTokenProvider = TokenOptions.DefaultEmailProvider;
});
var idBuilder = new IdentityBuilder(typeof(User), typeof(Role), services);
idBuilder.AddEntityFrameworkStores<TestDbContext>()
  .AddDefaultTokenProviders()
  .AddRoleManager<RoleManager<Role>>()
  .AddUserManager<UserManager<User>>();
// 注册 FluentValidation 服务
Assembly assembly = Assembly.GetExecutingAssembly();
builder.Services.AddFluentValidationAutoValidation()
  .AddFluentValidationClientsideAdapters()
  .AddValidatorsFromAssembly(assembly);
var app = builder.Build();
// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
  app.UseSwagger();
  app.UseSwaggerUI();
}
app.UseHttpsRedirection();
app.UseAuthorization();
app.MapControllers();
app.Run();

public record LoginRequest(string UserName, string Password);

using FluentValidation;
using Microsoft.EntityFrameworkCore;
public class LoginRequestValidator : AbstractValidator<LoginRequest>
{
  // 通过构造方法注入了TestDbContext
  public LoginRequestValidator(TestDbContext dbCtx)
  {
    RuleFor(x => x.UserName)
      .NotNull()
      // 使用TestDbContext服务检查用户名是否存在
      // 同步方式
      .Must(name => dbCtx.Users.Any(u => u.UserName == name))
      // 异步方式，但使用异步后出错，暂时未能找到解决方案
      //.MustAsync((name,_) => dbCtx.Users.AnyAsync(u => u.UserName == name))
      // 用Lambda表达式的形式使用模型类中的属性对报错信息进行格式化
      .WithMessage(c => $"用户名{c.UserName}不存在");
  }
}

using Microsoft.AspNetCore.Mvc;
namespace FluentValidationSample2.Controllers
{
  [ApiController]
  [Route("[controller]/[action]")]
  public class TestController : ControllerBase
  {
    [HttpPost]
    public ActionResult Login(LoginRequest req)
    {
      return Ok();
    }
  }
}