Golang Cookie结构体解析与操作辅助库

Cookie结构体解析

在Go语言中，net/http包提供了Cookie结构体，用于表示HTTP cookie。以下是Cookie结构体的定义：

type Cookie struct {
    Name       string
    Value      string
    Path       string
    Domain     string
    Expires    time.Time
    RawExpires string
    MaxAge     int
    Secure     bool
    HttpOnly   bool
    SameSite   SameSite
    Raw        string
    Unparsed   []string
}

各字段含义：

• Name: cookie名称
• Value: cookie值
• Path: cookie路径
• Domain: cookie域名
• Expires: cookie过期时间
• MaxAge: cookie有效期(秒)
• Secure: 是否仅通过HTTPS传输
• HttpOnly: 是否仅限HTTP访问(防止JavaScript访问)
• SameSite: 跨站请求策略

标准库操作示例

设置Cookie

http.HandleFunc("/set", func(w http.ResponseWriter, r *http.Request) {
    cookie := &http.Cookie{
        Name:     "session_id",
        Value:    "abc123",
        Path:     "/",
        MaxAge:   3600,
        HttpOnly: true,
        Secure:   true,
        SameSite: http.SameSiteLaxMode,
    }
    http.SetCookie(w, cookie)
    fmt.Fprintln(w, "Cookie set")
})

读取Cookie

http.HandleFunc("/get", func(w http.ResponseWriter, r *http.Request) {
    cookie, err := r.Cookie("session_id")
    if err != nil {
        if err == http.ErrNoCookie {
            fmt.Fprintln(w, "Cookie not found")
            return
        }
        http.Error(w, err.Error(), http.StatusBadRequest)
        return
    }
    fmt.Fprintf(w, "Cookie value: %s", cookie.Value)
})

删除Cookie

http.HandleFunc("/delete", func(w http.ResponseWriter, r *http.Request) {
    cookie := &http.Cookie{
        Name:   "session_id",
        Value:  "",
        Path:   "/",
        MaxAge: -1, // 设置为负值表示删除
    }
    http.SetCookie(w, cookie)
    fmt.Fprintln(w, "Cookie deleted")
})

辅助插件库推荐

1. gorilla/securecookie

gorilla/securecookie提供了安全的cookie编码/解码功能，防止cookie被篡改。

import "github.com/gorilla/securecookie"

var hashKey = securecookie.GenerateRandomKey(64)
var blockKey = securecookie.GenerateRandomKey(32)
var s = securecookie.New(hashKey, blockKey)

// 编码
func setSecureCookie(w http.ResponseWriter, name string, value map[string]string) {
    if encoded, err := s.Encode(name, value); err == nil {
        cookie := &http.Cookie{
            Name:  name,
            Value: encoded,
            Path:  "/",
        }
        http.SetCookie(w, cookie)
    }
}

// 解码
func getSecureCookie(r *http.Request, name string) (map[string]string, error) {
    cookie, err := r.Cookie(name)
    if err != nil {
        return nil, err
    }
    value := make(map[string]string)
    return value, s.Decode(name, cookie.Value, &value)
}

2. gofiber/fiber

Fiber框架提供了更简洁的cookie操作API：

import "github.com/gofiber/fiber/v2"

app := fiber.New()

// 设置cookie
app.Get("/set", func(c *fiber.Ctx) error {
    c.Cookie(&fiber.Cookie{
        Name:     "token",
        Value:    "123456",
        Expires:  time.Now().Add(24 * time.Hour),
        HTTPOnly: true,
        SameSite: "Lax",
    })
    return c.SendString("Cookie set")
})

// 获取cookie
app.Get("/get", func(c *fiber.Ctx) error {
    return c.SendString("Cookie value: " + c.Cookies("token"))
})

// 删除cookie
app.Get("/delete", func(c *fiber.Ctx) error {
    c.ClearCookie("token")
    return c.SendString("Cookie deleted")
})

3. go-chi/chi

Chi路由器的中间件方式处理cookie：

import "github.com/go-chi/chi"

func cookieMiddleware(next http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        // 读取或设置cookie
        cookie, err := r.Cookie("visits")
        if err != nil {
            cookie = &http.Cookie{
                Name:  "visits",
                Value: "1",
            }
        } else {
            visits, _ := strconv.Atoi(cookie.Value)
            cookie.Value = strconv.Itoa(visits + 1)
        }
        http.SetCookie(w, cookie)
        
        next.ServeHTTP(w, r)
    })
}

func main() {
    r := chi.NewRouter()
    r.Use(cookieMiddleware)
    // ...其他路由
}

自定义Cookie辅助函数

以下是一些常用的cookie操作辅助函数：

// 设置cookie
func SetCookie(w http.ResponseWriter, name, value string, maxAge int) {
    http.SetCookie(w, &http.Cookie{
        Name:     name,
        Value:    value,
        Path:     "/",
        MaxAge:   maxAge,
        HttpOnly: true,
        Secure:   true,
        SameSite: http.SameSiteLaxMode,
    })
}

// 获取cookie
func GetCookie(r *http.Request, name string) (string, error) {
    cookie, err := r.Cookie(name)
    if err != nil {
        return "", err
    }
    return cookie.Value, nil
}

// 删除cookie
func DeleteCookie(w http.ResponseWriter, name string) {
    http.SetCookie(w, &http.Cookie{
        Name:   name,
        Value:  "",
        Path:   "/",
        MaxAge: -1,
    })
}

// 检查cookie是否存在
func HasCookie(r *http.Request, name string) bool {
    _, err := r.Cookie(name)
    return err == nil
}

这些辅助库和函数可以简化cookie操作，提高开发效率，同时增强安全性。根据项目需求选择合适的工具，或基于标准库封装自己的cookie处理逻辑。