如果某些权限检查失败，如何提前终止我的处理程序？

Question

我正在寻找一种方法来实现权限检查功能，使用http

这个想法是有些API应该只由登录会话使用。

func CheckPermissionFilter(w http.ResponseWriter, r *http.Response){

    sid, err := r.Cookie("sid")

    // check the permission with sid, if permission is granted then just let the 

    // process go on, otherwise, just break the filter chain and return Http Error Code.

}

func SomeHttpHandler(w http.ResponseWriter, r *http.Response){

     CheckPermissionFilter(w, r)

     // if not breaked by above filter function, process the request...

   

}

我对权限检查没有问题，但我找不到破坏HTTP请求处理的方法。

Answer 1

处理程序中的调用不能提前终止后者。相反，您应该定义为中间件（另请参阅装饰器模式）：CheckPermissionFilterSomeHttpHandlerCheckPermissionFilterpackage mainimport (    "net/http")func main() {    http.Handle("/foo", CheckPermissionFilter(SomeHttpHandler))    // ...}func CheckPermissionFilter(h http.HandlerFunc) http.HandlerFunc {    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {        sid, err := r.Cookie("sid")        // handle err        if !Validate(sid) {            http.Error(w, "Unauthorized", http.StatusUnauthorized)            return        }        h(w, r)    })}func SomeHttpHandler(w http.ResponseWriter, r *http.Request) {    // ...}func Validate(sid string) bool {    return true // simplistic implementation for this example}