然后再startup类的ConfigureServices方法中增加读取配置信息

public void ConfigureServices(IServiceCollection services)
    {
      services.AddControllers();
      services.Configure<TokenManagement>(Configuration.GetSection("tokenManagement"));
      var token = Configuration.GetSection("tokenManagement").Get<TokenManagement>();

    }

到目前为止，我们完成了一些基础工作，下面再webapi中注入jwt的验证服务，并在中间件管道中启用authentication中间件。

startup类中要引用jwt验证服务的命名空间

using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.IdentityModel.Tokens;

然后在 ConfigureServices 方法中添加如下逻辑

services.AddAuthentication(x =>
      {
        x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
        x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
      }).AddJwtBearer(x =>
      {
        x.RequireHttpsMetadata = false;
        x.SaveToken = true;
        x.TokenValidationParameters = new TokenValidationParameters
        {
          ValidateIssuerSigningKey = true,
          IssuerSigningKey = new SymmetricSecurityKey(Encoding.ASCII.GetBytes(token.Secret)),
          ValidIssuer = token.Issuer,
          ValidAudience = token.Audience,
          ValidateIssuer = false,
          ValidateAudience = false
        };
      });

再 Configure 方法中启用验证

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
      if (env.IsDevelopment())
      {
        app.UseDeveloperExceptionPage();
      }

      app.UseHttpsRedirection();

      app.UseAuthentication();
      app.UseRouting();

      app.UseAuthorization();

      app.UseEndpoints(endpoints =>
      {
        endpoints.MapControllers();
      });
    }

上面完成了JWT验证的功能，下面就需要增加签发token的逻辑。我们需要增加一个专门用来用户认证和签发token的控制器，命名成 AuthenticationController ，同时增加一个请求的DTO类

public class LoginRequestDTO
  {
    [Required]
    [JsonProperty("username")]
    public string Username { get; set; }


    [Required]
    [JsonProperty("password")]
    public string Password { get; set; }
  }

[Route("api/[controller]")]
  [ApiController]
  public class AuthenticationController : ControllerBase
  {
    [AllowAnonymous]
     [HttpPost, Route("requestToken")]
    public ActionResult RequestToken([FromBody] LoginRequestDTO request)
    {
      if (!ModelState.IsValid)
      {
        return BadRequest("Invalid Request");
      }

      return Ok();

    }
  }

目前上面的控制器只实现了基本的逻辑，下面我们要创建签发token的服务，去完成具体的业务。第一步我们先创建对应的服务接口，命名为 IAuthenticateService

public interface IAuthenticateService
  {
    bool IsAuthenticated(LoginRequestDTO request, out string token);
  }