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前言

identity

ASP.NET Core提供了标识（identity）框架，它采用RBAC（role-based access control，基于角色的访问控制）策略，内置了对用户、角色等表的管理及相关的接口，从而简化了系统的开发。

CodeFirst

先创建实体类，再通过实体类反向的创建数据库和表结构

什么是JWT？
JSON WEB Token，是一种基于JSON的、用于在网络上声明某种主张的令牌（token）

JWT组成
JWT通常由三部分组成: 头信息（header）, 消息体（payload）和签名（signature）

头信息指定了该JWT使用的签名算法，HS256 表示使用了 HMAC-SHA256 来生成签名。
消息体包含了JWT的意图
未签名的令牌由base64url编码的头信息和消息体拼接而成（使用"."分隔），签名则通过私有的key计算而成。
最后在未签名的令牌尾部拼接上base64url编码的签名（同样使用"."分隔）就是JWT了
典型的JWT的格式：xxxxx.yyyyy.zzzzz

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一、创建上下文类

  安装Microsoft.EntityFrameworkCore

  安装Microsoft.AspNetCore.Identity.EntityFrameworkCore 

1.自定义MyContext上下文类继承IdentityDbContext

示例如下：

    public class MyContext : IdentityDbContext{public MyContext(DbContextOptions<MyContext> options) : base(options){}protected override void OnModelCreating(ModelBuilder modelBuilder){base.OnModelCreating(modelBuilder);      }}

2.在Program中添加AddDbContext服务

安装Microsoft.EntityFrameworkCore.SqlServer 

示例如下：

builder.Services.AddDbContext<MyContext>(options =>
{var connectionStr = builder.Configuration.GetConnectionString("SqlServer:Connection");options.UseSqlServer(connectionStr);
});

在配置文件中appsettings.json配置连接字符串

  "ConnectionStrings": {"sqlserver": {"Connection": "Server=服务器名称;User Id=账号;Password=密码;Database=数据库;MultipleActiveResultSets=true;Encrypt=True;TrustServerCertificate=True;"}}

二、使用Migration数据迁移

安装Microsoft.EntityFrameworkCore.Tools 

1.在控制台中 依次使用add-migration 、updatebase 命令 

如图所示

执行成功后 去数据库看数据库已经建立好了

效果如下：

2.如何修改表名 

生成的表都默认是带有AspNet 觉得不喜欢，那怎么修改呢

使用 FluentAPI配置

示例如下：

public class UserConfig : IEntityTypeConfiguration<IdentityUser>{public void Configure(EntityTypeBuilder<IdentityUser> builder){builder.ToTable("User");}}public class RoleConfig : IEntityTypeConfiguration<IdentityRole>{public void Configure(EntityTypeBuilder<IdentityRole> builder){builder.ToTable("Role");}}public class UserRoleConfig : IEntityTypeConfiguration<IdentityUserRole<string>>{public void Configure(EntityTypeBuilder<IdentityUserRole<string>> builder){builder.ToTable("UserRole");}}

 在OnModelCreating方法中加入

// 反射中找项目下所有 继承IEntityTypeConfiguration的配置modelBuilder.ApplyConfigurationsFromAssembly(this.GetType().Assembly);

再次执行add-migration 、updatebata 命令 

再去数据库查看

已经成功修改我们想要的表名了

3.如何自定义字段

比如我想在用户表中添加年龄字段，创建新的用户类去继承IdentityUser类

示例如下：

    public class User: IdentityUser{/// <summary>///   年龄/// </summary>public int? Age { get; set; }/// <summary>/// 备注/// </summary>public string ReMark { get; set; }}

在UserConfig类中修改成User

        public class UserConfig : IEntityTypeConfiguration<User>{public void Configure(EntityTypeBuilder<User> builder){builder.Property(x => x.Id).HasColumnOrder(1);//字段排序builder.Property(x => x.Age).IsRequired(false); //可以为空builder.Property(x => x.ReMark).HasMaxLength(200).IsRequired(false); //指定长度 ,可以为空builder.ToTable("User");}}

注意：上下文MyContext:IdentityDbContext需要修改成MyContext:IdentityDbContext<User>

这时候 再去执行migration命令，再去看数据库，已经加上了

效果如下： 

三、使用Identity实现登录、修改密码

1.在Program中 添加AddIdentityCore服务、AddRoleManager、AddUserManager配置

示例如下： 

builder.Services.AddIdentityCore<User>(options =>
{//配置用户名options.User = new UserOptions{RequireUniqueEmail = false, //要求Email唯一//AllowedUserNameCharacters = "abcdefgABCDEFG123456789" //允许的用户名字符，默认是 abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-._@+};//配置密码options.Password = new PasswordOptions{RequiredLength = 6, //要求密码最小长度，默认是 6 个字符RequireDigit = true, //要求有数字RequiredUniqueChars = 1, //要求至少要出现的字母数RequireLowercase = false, //要求小写字母RequireNonAlphanumeric = false, //要求特殊字符RequireUppercase = false //要求大写字母};//锁定账户options.Lockout = new LockoutOptions{AllowedForNewUsers = true, // 新用户锁定账户DefaultLockoutTimeSpan = TimeSpan.FromMinutes(1), //锁定时长，默认是 5 分钟MaxFailedAccessAttempts = 3 //登录错误最大尝试次数，默认 5 次};//令牌配置//打开此 设置 为 短验证码 不打开为 长验证码options.Tokens.PasswordResetTokenProvider = TokenOptions.DefaultEmailProvider;options.Tokens.EmailConfirmationTokenProvider = TokenOptions.DefaultEmailProvider;});
var idBuilder = new IdentityBuilder(typeof(User), typeof(IdentityRole), builder.Services);
idBuilder.AddEntityFrameworkStores<MyContext>().AddDefaultTokenProviders().AddRoleManager<RoleManager<IdentityRole>>().AddUserManager<UserManager<User>>();

2.在控制器注入UserManager、RoleManager服务

示例如下： 

    [ApiController][Route("[controller]/[action]")]public class UserController : ControllerBase{private readonly UserManager<User> _userManager;public UserController(UserManager<User> userManager){_userManager = userManager;}/// <summary>/// 创建用户/// </summary>/// <returns></returns>[HttpPost]public async Task<IActionResult> CreateUser(LoginRequest loginRequest){    User user = await _userManager.FindByNameAsync(loginRequest.UserName);if (user == null){user = new User{UserName = loginRequest.UserName};var result = await _userManager.CreateAsync(user, loginRequest.Password);if (!result.Succeeded){return BadRequest(result.Errors);}         }return Ok();}/// <summary>/// 登录/// </summary>/// <param name="loginRequest"></param>/// <returns></returns>[HttpPost]public async Task<IActionResult> Login(LoginRequest loginRequest){string userName = loginRequest.UserName;string password = loginRequest.Password;var user = await _userManager.FindByNameAsync(userName);if (user == null){return NotFound($"用户名{userName}不存在!");}var islocked = await _userManager.IsLockedOutAsync(user);if (islocked){return BadRequest("用户已锁定！");}var success = await _userManager.CheckPasswordAsync(user, password);if (success){return Ok();}else{var r = await _userManager.AccessFailedAsync(user);if (!r.Succeeded){return BadRequest("访问失败信息写入错误！");}else{return BadRequest("失败！");}}}/// <summary>/// 修改密码/// </summary>/// <param name="req"></param>/// <returns></returns>[HttpPost]public async Task<IActionResult> ChangePassword(ChangePasswordRequest req){    var user = await _userManager.FindByNameAsync(req.UserName);if (user == null){return NotFound($"用户名{req.UserName}不存在!");}var result = await _userManager.ChangePasswordAsync(user,req.oldPassword,req.newPassWord);if (!result.Succeeded){return BadRequest("修改失败！");}return Ok("Success");}#region 通过发送邮箱的方式重置密码/// <summary>/// 重置密码发送Token/// </summary>/// <param name="req"></param>/// <returns></returns>[HttpPost]public async Task<IActionResult> SendResetPasswordToken(SendResetPasswordTokenRequest req){string email = req.Email;var user = await _userManager.FindByEmailAsync(email);if (user == null){return NotFound($"邮箱不存在{email}");}string token = await _userManager.GeneratePasswordResetTokenAsync(user);return Ok($"向邮箱{user.Email}发送Token={token}");}/// <summary>/// 重置密码/// </summary>/// <param name="req"></param>/// <returns></returns>[HttpPost]public async Task<IActionResult> ResetPasswordToken(ResetPasswordRequest req){string userName = req.UserName;var user = await _userManager.FindByNameAsync(userName);if (user == null){return NotFound($"用户名{userName}不存在!");}var islocked = await _userManager.IsLockedOutAsync(user);if (islocked){return BadRequest("用户已锁定！");}var result = await _userManager.ResetPasswordAsync(user, req.token,req.newPassWord);if (!result.Succeeded){return BadRequest("修改失败！");}return Ok("Success");}#endregion}public record LoginRequest(string UserName, string Password);public record ChangePasswordRequest(string UserName, string oldPassword,string newPassWord);public record SendResetPasswordTokenRequest(string Email);public record ResetPasswordRequest(string UserName, string token,string newPassWord);

四、使用JWT实现权限验证

安装Microsoft.AspNetCore.Authentication.JwtBearer

1.在启动类Program.cs中配置Swagger可以输入身份验证方式

示例如下： 

builder.Services.AddSwaggerGen(options =>
{options.AddSecurityDefinition("Bearer", new OpenApiSecurityScheme{Description = "请输入token,格式为 Bearer xxxxxxxx（注意中间必须有空格）",Name = "Authorization",//jwt默认的参数名称In = ParameterLocation.Header,//jwt默认存放Authorization信息的位置(请求头中)Type = SecuritySchemeType.ApiKey,BearerFormat = "JWT",Scheme = "Bearer"});//添加安全要求options.AddSecurityRequirement(new OpenApiSecurityRequirement {{new OpenApiSecurityScheme{Reference =new OpenApiReference{Type = ReferenceType.SecurityScheme,Id ="Bearer"}},new string[]{ }}});});

2.配置类信息、AddAuthentication服务

示例如下：

    public class JWTOptions{/// <summary>/// 颁发者        /// </summary>public string Issuer { get; set; }/// <summary>/// 接收者       /// </summary>public string Audience { get; set; } /// <summary>/// 密钥/// </summary>public string SigningKey { get; set; }/// <summary>/// 过期时间/// </summary>public int ExpireSeconds { get; set; }}

在配置文件appsettings.json中加入以下信息

  "JWT": {"Issuer": "我是小小鱼","Audience": "我是小小鱼","SigningKey": "fasdfad&9045dafz222#fadpio@0232","ExpireSeconds": "3600"}

在添加AddAuthentication服务

builder.Services.Configure<JWTOptions>(builder.Configuration.GetSection("JWT"));
builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
.AddJwtBearer(x =>
{var jwtOpt = builder.Configuration.GetSection("JWT").Get<JWTOptions>();byte[] keyBytes = Encoding.UTF8.GetBytes(jwtOpt.SigningKey);var secKey = new SymmetricSecurityKey(keyBytes);x.TokenValidationParameters = new(){ValidateIssuer = true,//是否验证IssuerValidateAudience = true,//是否验证AudienceValidateIssuerSigningKey = true,//是否验证SecurityKeyValidIssuer = jwtOpt.Issuer,ValidAudience=jwtOpt.Audience,IssuerSigningKey = secKey,ValidateLifetime = true, //是否验证失效时间ClockSkew = TimeSpan.FromSeconds(4)};
});

 创建一个Jwt辅助类

  public class JwtHelper{public static string BuildToken(IEnumerable<Claim> claims, JWTOptions options){DateTime expires = DateTime.Now.AddSeconds(options.ExpireSeconds);byte[] keyBytes = Encoding.UTF8.GetBytes(options.SigningKey);var secKey = new SymmetricSecurityKey(keyBytes);var credentials = new SigningCredentials(secKey,SecurityAlgorithms.HmacSha256Signature);var tokenDescriptor = new JwtSecurityToken(options.Issuer,options.Audience,expires: expires,signingCredentials: credentials, claims: claims);return new JwtSecurityTokenHandler().WriteToken(tokenDescriptor);}}

3.在登录的接口中返回token

示例如下：

        /// <summary>/// 登录/// </summary>/// <param name="loginRequest"></param>/// <returns></returns>[HttpPost]public async Task<IActionResult> Login(LoginRequest loginRequest,[FromServices] IOptions<JWTOptions> jwtOptions){string userName = loginRequest.UserName;string password = loginRequest.Password;var user = await _userManager.FindByNameAsync(userName);if (user == null){return NotFound($"用户名{userName}不存在!");}var islocked = await _userManager.IsLockedOutAsync(user);if (islocked){return BadRequest("用户已锁定！");}var success = await _userManager.CheckPasswordAsync(user, password);if (success){var claims = new List<Claim>();claims.Add(new Claim(ClaimTypes.NameIdentifier, user.Id.ToString()));claims.Add(new Claim(ClaimTypes.Name, user.UserName));var roles = await _userManager.GetRolesAsync(user);foreach (string role in roles){claims.Add(new Claim(ClaimTypes.Role, role));}string Token = JwtHelper.BuildToken(claims, jwtOptions.Value);return Ok(Token);}else{var r = await _userManager.AccessFailedAsync(user);if (!r.Succeeded){return BadRequest("访问失败信息写入错误！");}else{return BadRequest("失败！");}}}

效果如下

4.在需要鉴权的接口加上 [Authorize]

示例如下：

        /// <summary>/// 获取用户信息/// </summary>/// <returns></returns>[HttpPost][Authorize]public async Task<IActionResult> GetUser() {var claimsPrincipal = this.HttpContext.User;var name = claimsPrincipal.Claims.FirstOrDefault(r => r.Type == "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name")?.Value;var user = await _userManager.FindByNameAsync(name);if (user == null){return BadRequest("token有误");}return Ok($"获取用户名：{user.UserName},邮箱：{user.Email}");}

运行效果

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总结

以上简单用Identity框架在通过migration命令建库建表，再使用 FluentAPI配置表名、字段,用dentity框架封装的UserManager实现登录、修改密码，以及通过token实现鉴权