Token refresh的实现
实现原理:
在access_token里加入refresh_token标识,给access_token设置短时间的期限(例如一天),给refresh_token设置长时间的期限(例如七天)。当活动用户(拥有access_token)发起request时,在权限验证里,对于requeset的header包含的access_token、refresh_token分别进行验证:
1、access_token没过期,即通过权限验证;
2、access_token过期,refresh_token没过期,则返回权限验证失败,并在返回的response的header中加入标识状态的key,在request方法的catch中通过webException来获取标识的key,获取新的token(包含新的access_token和refresh_token),再次发起请求,并返回给客户端请求结果以及新的token,再在客户端更新公共静态token模型;
3、access_token过期,refresh_token过期即权限验证失败。
下面展示一下关键代码:
一、登录生成token的时候加入refresh标识
- public TOKEN GetToken(string username, string password)
- {
- TOKEN token = new TOKEN();
- U_USER model = new BLLU_USER().Token(username, password);
- if (model != null)
- {
- string pwd = new SDDMD().MD5_jie(model.USERPWD);
- string md5 = new SDDMD().MD5_jia(model.USERID +"&"+ DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") +"&"+ pwd
+"&refresh"+ DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));- token.access_token = md5;
- token.token_type = "Authorization";
- token.expires_in = DateTime.Now.ToString("yyyyMMddHHmmss");
- //token.refresh_token = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + "&refresh";
- }
- return token;
- }
二、在权限验证环节,对于access_token、refresh_token设置不同时间的期限。再根据判断结果返回状态。
- /// <summary>
- /// 校验token是否有效
- /// </summary>
- /// <param name="encryptTicket">用户提交的Token值</param>
- /// <returns></returns>
- private int ValidateTicket(string encryptTicket)
- {
- try
- {
- var strTicket = new DBUtility.SDDMD().MD5_jie(encryptTicket);
- string[] TicketMsg = strTicket.Split('&');
- if (TicketMsg.Length == 4)
- {
- string username = TicketMsg[0];//用户名
- string passwrod = TicketMsg[2];//密码
- U_USER model = new BLL.BLLU_USER().Token(username, passwrod);//登陆验证
- if (model != null)
- {
- _userModel = model;
- //定义Access_Token有效期为1天,精确到秒
- DateTime dt = Convert.ToDateTime(TicketMsg[1]).AddDays(1);
- //定义Refresh_Token有效期为1天,精确到秒
- DateTime dtNew= Convert.ToDateTime(TicketMsg[3].Substring(7)).AddDays(7);//
- if (dt > DateTime.Now)
- return 1; //1:access_token没过期
- else
- {
- if (dtNew > DateTime.Now)
- return 2; //2:access_token过期,refresh_token没过期
- else
- return 3; //3:access_token过期,refresh_token过期
- }
- }
- else
- return 3;
- }
- else
- return 3;
- }
- catch { return 3; }
- }
三、根据反馈的状态执行不同的方法,“2”(access_token过期,refresh_token没过期)状态下,给返回失败的response的header中加入识别的key值。
- /// <summary>
- /// 定义Access_token验证过期但Reflesh_token有效返回请求刷新token的信息
- /// </summary>
- /// <param name="actionContext"></param>
- protected void RefreshToken(HttpActionContext actionContext)
- {
- var content = "refreshtoken";
- base.HandleUnauthorizedRequest(actionContext);
- var response = actionContext.Response;
- response.StatusCode = HttpStatusCode.Forbidden;
- response.Content = new StringContent(content, Encoding.UTF8, "application/json");
- response.Headers.Add("token", "refresh");//加入识别的key值
- }
四、request方法中通过Catch捕获webException对象获取Key值,并获取新的token(包含新的access_token和refresh_token),再次发起请求,并返回给客户端请求结果以及新的token。
- /// <summary>
- /// Get head中携带token发送请求
- /// </summary>
- /// <param name="url">WebAPI访问路径</param>
- /// <param name="tokentype">token验证方式 《Authorization》</param>
- /// <param name="tokenvalue">token 《"Bearer " + Token》</param>
- /// <returns></returns>
- public string GetRequest(string url, string tokentype, string tokenvalue)
- {
- try
- {
- string responseStr = string.Empty;
- WebRequest request = WebRequest.Create(http + url);
- request.Timeout = 60000;
- request.Method = "Get";
- request.Headers.Add(tokentype, tokenvalue);
- var response = request.GetResponse();
- Stream ReceiveStream = response.GetResponseStream();
- using (StreamReader stream = new StreamReader(ReceiveStream, Encoding.UTF8))
- {
- responseStr = stream.ReadToEnd();
- }
- return responseStr;
- }
- catch (WebException e)
- {
- using (WebResponse response = e.Response)
- {
- string result=response.Headers.Get("token");//获取识别的KEY
- if (result == "refresh")//验证是否为状态“2”方法所加的key值
- {
- var strTicket = new SDDMD().MD5_jie(tokenvalue.Substring(6));
- string[] TicketMsg = strTicket.Split('&');
- string username = TicketMsg[0];//用户名
- string passwrod = TicketMsg[2];//密码
- string responseStr = GetRequest("CYUMS/Token/" + username + "/" + passwrod);//获取新的token
- TOKEN tokenmodel = JsonConvert.DeserializeObject<TOKEN>(responseStr);
- string secondResponseStr= GetRequest(url, tokenmodel.token_type, "Haval " + tokenmodel.access_token);//再次发起请求
- return secondResponseStr + "|" + responseStr;//返回请求结果以及新的token
- }
- else
- throw e;
- }
- }
- }
五、客户端识别token是否更新,如果更新,就更新公共静态token模型中的access_token的值;
- string user = new HttpHelper().GetRequest(getUserModel, tokenmodel.token_type, "Haval " + tokenmodel.access_token);
- string[] str = user.Split('|');
- if (str.Length == 2)//判断是否有token更新
- {
- TOKEN tokens = JsonConvert.DeserializeObject<TOKEN>(str[1]);
- tokenmodel.access_token = tokens.access_token;
- }
- U_USER users = JsonConvert.DeserializeObject<U_USER>(str[0]);
- //business code...