HTTP 重定向未呈现新页面

Golang不知道大家是否熟悉？今天我将给大家介绍《HTTP 重定向未呈现新页面》，这篇文章主要会讲到等等知识点，如果你在看完本篇文章后，有更好的建议或者发现哪里有问题，希望大家都能积极评论指出，谢谢！希望我们能一起加油进步！

我让用户登陆登录页面。当他们成功登录后，这应该将他们重定向到用户页面。然而这并没有发生，我不确定为什么。似乎 ajax 调用由于某种原因进入错误（我不确定为什么）。不过，当我在响应文本中记录新页面已通过的响应时，我可以看到。

应重定向用户的登录方法：

// this map stores the users sessions. for larger scale applications, you can use a database or cache for this purpose
var sessions = map[string]session{}

// each session contains the username of the user and the time at which it expires
type session struct {
    username string
    expiry   time.time
}

// we'll use this method later to determine if the session has expired
func (s session) isexpired() bool {
    return s.expiry.before(time.now())
}

// credentials create a struct that models the structure of a user in the request body
type credentials struct {
    password string `json:"password"`
    username string `json:"username"`
}

func login(w http.responsewriter, r *http.request) {
    log.println("login started")

    var creds credentials
    // get the json body and decode into credentials
    if err := json.newdecoder(r.body).decode(&creds); err != nil {
        // if the structure of the body is wrong, return an http error
        log.println(err)
        w.writeheader(http.statusbadrequest)
        return
    }

    // get the expected password from our in memory map
    expectedpassword, ok := "test", true

    // if a password exists for the given user
    // and, if it is the same as the password we received, then we can move ahead
    // if not, then we return an "unauthorized" status
    if !ok || expectedpassword != creds.password {
        log.println("bad password")
        w.writeheader(http.statusunauthorized)
        return
    }

    // create a new random session token
    // we use the "github.com/google/uuid" library to generate uuids
    sessiontoken := uuid.newstring()
    expiresat := time.now().add(120 * time.second)

    // set the token in the session map, along with the session information
    sessions[sessiontoken] = session{
        username: creds.username,
        expiry:   expiresat,
    }

    // finally, we set the client cookie for "session_token" as the session token we just generated
    // we also set an expiry time of 120 seconds
    http.setcookie(w, &http.cookie{
        name:    "session_token",
        value:   sessiontoken,
        expires: expiresat,
    })

    log.println("login success")

    http.redirect(w, r, "/users", http.statusfound)
}

ajax 调用：

function handleSubmit(evt) {
            evt.preventDefault();
            let form = evt.target;
            let data = new FormData(form);
            if (data.get("username") != null && data.get("username") != "") {
                $.ajax({
                    url: '/login',
                    method: 'post',
                    data: JSON.stringify(Object.fromEntries(data)),
                    dataType: 'json',
                    success: (resp) => {
                        if (resp.redirect) {
                            // resp.redirect contains the string URL to redirect to
                            window.location.redirect = resp.redirect;
                        }
                    },
                    error: (resp) => {
                        console.log("An error occurred. Please try again");
                        console.log(resp)
                    }
                });
            }
            return false
        }

正确答案

所以要解决您的问题，您应该稍微修改一下您的服务器代码

func login(w http.responsewriter, r *http.request) {
    w.header().set("content-type", "application/json; charset=utf-8")

    log.println("login started")

    var creds credentials
    // get the json body and decode into credentials
    if err := json.newdecoder(r.body).decode(&creds); err != nil {
        // if the structure of the body is wrong, return an http error
        log.println(err)
        w.writeheader(http.statusbadrequest)
        return
    }

    // get the expected password from our in memory map
    expectedpassword, ok := "test", true

    // if a password exists for the given user
    // and, if it is the same as the password we received, then we can move ahead
    // if not, then we return an "unauthorized" status
    if !ok || expectedpassword != creds.password {
        log.println("bad password")
        w.writeheader(http.statusunauthorized)
        return
    }

    // create a new random session token
    // we use the "github.com/google/uuid" library to generate uuids
    sessiontoken := uuid.newstring()
    expiresat := time.now().add(120 * time.second)

    // set the token in the session map, along with the session information
    sessions[sessiontoken] = session{
        username: creds.username,
        expiry:   expiresat,
    }

    // finally, we set the client cookie for "session_token" as the session token we just generated
    // we also set an expiry time of 120 seconds
    http.setcookie(w, &http.cookie{
        name:    "session_token",
        value:   sessiontoken,
        expires: expiresat,
    })

    log.println("login success")

    by, _ := json.marshal(map[string]interface{}{
        "to": "http://localhost:8085/users",
    })

    w.write(by)
}

我使用 json 响应而不是 http.redirect。 回到你的ajax调用，我再次将数据类型更改为json，因为我们的服务器现在发送json。将 if 条件从 resp.redirect 更改为 resp.to，并使用 window.location.href 而不是 windows.location.redirect。

function handleSubmit(evt) {
            evt.preventDefault();
            let form = evt.target;
            let data = new FormData(form);
            if (data.get("username") != null && data.get("username") != "") {
                $.ajax({
                    url: 'http://localhost:8085/login',
                    method: 'post',
                    data: JSON.stringify(Object.fromEntries(data)),
                    dataType: 'json',
                    success: (resp) => {
                        if (resp.to) {
                            window.location.href = resp.to;
                        }
                    },
                    error: (resp) => {
                        console.log("An error occurred. Please try again");
                        console.log(resp)
                    }
                });
            }
            return false
        }

到这里，我们也就讲完了《HTTP 重定向未呈现新页面》的内容了。个人认为，基础知识的学习和巩固，是为了更好的将其运用到项目中，欢迎关注golang学习网公众号，带你了解更多关于的知识点！