TokenHelper：
public class TokenHelper : ITokenHelper { private IOptions<JWTConfig> _options; public TokenHelper(IOptions<JWTConfig> options) { _options = options; } public Token CreateToken(User user) { Claim[] claims = { new Claim(ClaimTypes.NameIdentifier,user.Code),new Claim(ClaimTypes.Name,user.Name) }; return CreateToken(claims); } private Token CreateToken(Claim[] claims) { var now = DateTime.Now;var expires = now.Add(TimeSpan.FromMinutes(_options.Value.AccessTokenExpiresMinutes)); var token = new JwtSecurityToken( issuer: _options.Value.Issuer, audience: _options.Value.Audience, claims: claims, notBefore: now, expires: expires, signingCredentials: new SigningCredentials(new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_options.Value.IssuerSigningKey)), SecurityAlgorithms.HmacSha256)); return new Token { TokenContent = new JwtSecurityTokenHandler().WriteToken(token), Expires = expires }; } }
通过CreateToken方法创建Token，这里有几个关键参数：
issuer Token发布者
Audience Token接受者
expires 过期时间
IssuerSigningKey 签名秘钥
对应的Token代码如下：
public class Token { public string TokenContent { get; set; } public DateTime Expires { get; set; } }
这样通过TokenHelper的CreateToken方法生成了一个Token返回给了客户端。到现在来看，貌似所有的工作已经完成了。并非如此，我们还需要在Startup文件中做一些设置。
public class Startup { // 。。。。。。此处省略部分代码 public void ConfigureServices(IServiceCollection services) { //读取配置信息 services.AddSingleton<ITokenHelper, TokenHelper>(); services.Configure<JWTConfig>(Configuration.GetSection("JWT")); //启用JWT services.AddAuthentication(Options => { Options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme; Options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme; }). AddJwtBearer(); services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2); } public void Configure(IApplicationBuilder app, IHostingEnvironment env) { if (env.IsDevelopment()) { app.UseDeveloperExceptionPage(); } //启用认证中间件 app.UseAuthentication(); app.UseMvc(); } }
