一、開發環境

VS2017  enterprise

win10 Pro 64

.net 4.6.2

二、開發過程

1、使用VS2017 建立.netframework專案，選擇WebApi

2、從Nuget包中搜索並安裝JWT

3、在Models中建立AuthInfo.cs、LoginRequest.cs、TokenInfo.cs三個類

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace apiToken.Models
{
    /// <summary>
    /// 身份驗證資訊 模擬JWT的payload
    /// </summary>
    public class AuthInfo
    {
        /// <summary>
        /// 使用者名稱
        /// </summary>
        public string UserName { get; set; }

        /// <summary>
        /// 角色
        /// </summary>
        public List<string> Roles { get; set; }

        /// <summary>
        /// 是否管理員
        /// </summary>
        public bool IsAdmin { get; set; }

        /// <summary>
        /// 口令過期時間
        /// </summary>
        public DateTime? ExpiryDateTime { get; set; }
    }
}
 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace apiToken.Models
{
    /// <summary>
    /// 登入使用者資訊
    /// </summary>
    public class LoginRequest
    {
        /// <summary>
        /// 使用者名稱
        /// </summary>
        public string UserName { get; set; }

        /// <summary>
        /// 密碼
        /// </summary>
        public string Password { get; set; }
    }
}
 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace apiToken.Models
{
    /// <summary>
    /// 生成的口令資訊
    /// </summary>
    public class TokenInfo
    {
        /// <summary>
        /// 是否成功
        /// </summary>
        public bool Success { get; set; }
        /// <summary>
        /// 令牌
        /// </summary>
        public string Token { get; set; }
        /// <summary>
        /// 錯誤資訊
        /// </summary>
        public string Message { get; set; }
    }
}
 

4、在Controllers資料夾下建立TokenController.cs檔案，生成口令

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using JWT;
using JWT.Algorithms;
using JWT.Serializers;
using apiToken.Models;
using System.Text;

namespace apiToken.Controllers
{
    [RoutePrefix("api/Token")]
    public class TokenController : ApiController
    {
        /// <summary>
        /// 登入
        /// </summary>
        /// <param name="loginRequest"></param>
        /// <returns></returns>
        [HttpPost]
        [Route("Login")]
        public TokenInfo Login([FromBody] LoginRequest loginRequest)
        {
            TokenInfo tokenInfo = new TokenInfo();//需要返回的口令資訊
            if (loginRequest != null)
            {
                string userName = loginRequest.UserName;
                string passWord = loginRequest.Password;
                bool isAdmin = (userName == "admin")?true:false;
                //模擬資料庫資料，真正的資料應該從資料庫讀取
                //身份驗證資訊
                AuthInfo authInfo = new AuthInfo { UserName=userName,Roles=new List<string> {"admin","commonrole"}, IsAdmin= isAdmin, ExpiryDateTime=DateTime.Now.AddHours(2)};
                const string secretKey = "Hello World";//口令加密祕鑰
                try
                {
                    byte[] key = Encoding.UTF8.GetBytes(secretKey);
                    IJwtAlgorithm algorithm = new HMACSHA256Algorithm();//加密方式
                    IJsonSerializer serializer = new JsonNetSerializer();//序列化Json
                    IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();//base64加解密
                    IJwtEncoder encoder = new JwtEncoder(algorithm, serializer, urlEncoder);//JWT編碼
                    var token = encoder.Encode(authInfo, key);//生成令牌
                    //口令資訊
                    tokenInfo.Success = true;
                    tokenInfo.Token = token;
                    tokenInfo.Message = "OK";
                }
                catch(Exception ex)
                {
                    tokenInfo.Success = false;
                    tokenInfo.Message = ex.Message.ToString();
                }
            }
            else
            {
                tokenInfo.Success = false;
                tokenInfo.Message = "使用者資訊為空";
            }
            return tokenInfo;
        }

        
    }
}

5、在專案中新增AuthAttributes資料夾，並且在資料夾在建立ApiAuthorizeAttribute.cs檔案，用於建立身份攔截器

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Http;
using System.Web.Http.Controllers;
using JWT;
using JWT.Serializers;
using apiToken.Models;
using System.Text;
using System.Net;
using System.Net.Http;

namespace apiToken.AuthAttributes
{
    /// <summary>
    /// 身份認證攔截器
    /// </summary>
    public class ApiAuthorizeAttribute: AuthorizeAttribute
    {
        /// <summary>
        /// 指示指定的控制元件是否已獲得授權
        /// </summary>
        /// <param name="actionContext"></param>
        /// <returns></returns>
        protected override bool IsAuthorized(HttpActionContext actionContext)
        {
            //前端請求api時會將token存放在名為"auth"的請求頭中
            var authHeader = from t in actionContext.Request.Headers where t.Key == "auth" select t.Value.FirstOrDefault();
            if (authHeader != null)
            {
                const string secretKey = "Hello World";//加密祕鑰
                string token = authHeader.FirstOrDefault();//獲取token
                if (!string.IsNullOrEmpty(token))
                {
                    try
                    {
                        byte[] key = Encoding.UTF8.GetBytes(secretKey);
                        IJsonSerializer serializer = new JsonNetSerializer();
                        IDateTimeProvider provider = new UtcDateTimeProvider();
                        IJwtValidator validator = new JwtValidator(serializer, provider);
                        IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
                        IJwtDecoder decoder = new JwtDecoder(serializer, validator, urlEncoder);
                        //解密
                        var json = decoder.DecodeToObject<AuthInfo>(token, key, verify: true);
                        if (json != null)
                        {
                            //判斷口令過期時間
                            if (json.ExpiryDateTime < DateTime.Now)
                            {
                                return false;
                            }
                            actionContext.RequestContext.RouteData.Values.Add("auth", json);
                            return true;
                        }
                        return false;
                    }
                    catch (Exception ex)
                    {
                        return false;
                    }
                }
            }
            return false;
        }

        /// <summary>
        /// 處理授權失敗的請求
        /// </summary>
        /// <param name="actionContext"></param>
        protected override void HandleUnauthorizedRequest(HttpActionContext actionContext)
        {
            var erModel = new
            {
                Success="false",
                ErrorCode="401"
            };
            actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.OK, erModel, "application/json");
        }

        /// <summary>
        ///  為操作授權時呼叫
        /// </summary>
        /// <param name="actionContext"></param>
        //public override void OnAuthorization(HttpActionContext actionContext)
        //{
          
        //}
    }
}

6、建立UserInfoController.cs 用於測試身份驗證

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using apiToken.AuthAttributes;
using Newtonsoft.Json;

namespace apiToken.Controllers
{
    [RoutePrefix("api/UserInfo")]
    [ApiAuthorize]
    public class UserInfoController : ApiController
    {
        /// <summary>
        /// 獲取使用者資訊
        /// </summary>
        /// <returns></returns>
        [HttpGet]
        [Route("GetUserInfo")]
        public string GetUserInfo()
        {
            var userInfo = new
            {
                UserName="test",
                Tel="123456789",
                Address="testddd"
            };
            return JsonConvert.SerializeObject(userInfo);
        }       
    }
}

最後將webapi介面在IIS中釋出，通過PostMan進行測試

如果Token不正確或者Token失效則不會進入請求

注：如果遇到跨域的問題，可以下webconfig中做如下配置