如何自定义.NET 8 Identity路由：扩展MapIdentityApi注册登录端点

一、扩展/register和/login端点支持用户名 #

1. 自定义注册请求模型 #

创建包含独立用户名字段的注册请求类：

public class CustomRegisterRequest
{
    [Required]
    public string Username { get; set; } = string.Empty;
    
    [Required]
    [EmailAddress]
    public string Email { get; set; } = string.Empty;
    
    [Required]
    [DataType(DataType.Password)]
    public string Password { get; set; } = string.Empty;
}

2. 替换默认/register端点 #

在Program.cs中手动映射自定义注册逻辑，替代默认的IdentityApi注册端点：

// 保留IdentityApi基础服务配置（使用你扩展的AppUser类）
builder.Services.AddIdentityApiEndpoints<AppUser>()
    .AddEntityFrameworkStores<AppDbContext>();

// 自定义注册端点
app.MapPost("/register", async (CustomRegisterRequest request, UserManager<AppUser> userManager) =>
{
    var user = new AppUser
    {
        UserName = request.Username, // 手动设置用户名，不再复用邮箱
        Email = request.Email
        // 此处可直接赋值你的扩展字段，比如 FullName = request.FullName
    };

    var createResult = await userManager.CreateAsync(user, request.Password);
    if (!createResult.Succeeded)
    {
        return Results.BadRequest(createResult.Errors);
    }

    // 可选：生成邮箱确认令牌并发送邮件
    var confirmToken = await userManager.GenerateEmailConfirmationTokenAsync(user);
    // 邮件发送逻辑自行实现

    return Results.Ok(new { UserId = user.Id });
})
.AllowAnonymous();

3. 让/login支持用户名登录 #

创建支持用户名/邮箱双输入的登录请求类，并自定义登录逻辑：

public class CustomLoginRequest
{
    [Required]
    public string LoginId { get; set; } = string.Empty; // 可传入用户名或邮箱
    
    [Required]
    [DataType(DataType.Password)]
    public string Password { get; set; } = string.Empty;
    
    public bool RememberMe { get; set; }
}

映射自定义登录端点：

app.MapPost("/login", async (CustomLoginRequest request, SignInManager<AppUser> signInManager) =>
{
    // 先尝试按邮箱查找，再按用户名查找
    var user = await signInManager.UserManager.FindByEmailAsync(request.LoginId) 
               ?? await signInManager.UserManager.FindByNameAsync(request.LoginId);

    if (user == null)
    {
        return Results.Unauthorized();
    }

    // 验证密码并生成令牌
    var signInResult = await signInManager.CheckPasswordSignInAsync(user, request.Password, request.RememberMe);
    if (!signInResult.Succeeded)
    {
        return Results.Unauthorized();
    }

    var accessToken = await signInManager.CreateUserTokenAsync(user, "Identity.Application", "AccessToken");
    return Results.Ok(new { AccessToken = accessToken });
})
.AllowAnonymous();

二、扩展IdentityUser字段后更新端点 #

默认IdentityApi端点使用内置模型，不会自动包含扩展字段，需手动修改请求/响应逻辑：

1. 注册时保存扩展字段 #

在CustomRegisterRequest中添加扩展字段：

public class CustomRegisterRequest
{
    // 原有Username、Email、Password字段
    [Required]
    public string FullName { get; set; } = string.Empty;
    
    [Phone]
    public string PhoneNumber { get; set; } = string.Empty;
}

在注册逻辑中赋值扩展字段：

var user = new AppUser
{
    UserName = request.Username,
    Email = request.Email,
    FullName = request.FullName,
    PhoneNumber = request.PhoneNumber
};

2. 修改端点返回包含扩展字段 #

自定义用户信息响应模型，并覆盖默认的/me端点：

public class UserResponse
{
    public string Id { get; set; } = string.Empty;
    public string Username { get; set; } = string.Empty;
    public string Email { get; set; } = string.Empty;
    public bool EmailConfirmed { get; set; }
    // 添加你的扩展字段
    public string FullName { get; set; } = string.Empty;
    public string PhoneNumber { get; set; } = string.Empty;
}

映射自定义/me端点：

app.MapGet("/me", async (ClaimsPrincipal user, UserManager<AppUser> userManager) =>
{
    var appUser = await userManager.GetUserAsync(user);
    if (appUser == null)
    {
        return Results.Unauthorized();
    }

    return Results.Ok(new UserResponse
    {
        Id = appUser.Id,
        Username = appUser.UserName!,
        Email = appUser.Email!,
        EmailConfirmed = appUser.EmailConfirmed,
        FullName = appUser.FullName,
        PhoneNumber = appUser.PhoneNumber!
    });
})
.RequireAuthorization();

内容的提问来源于stack exchange，提问作者noahkriesi