http - 如何限制用 golang 编写的 Web 服务器允许特定地址而不是模式？

Question

当我使用

http.HandleFunc("/", serveRest)  //serveRest is the method to handle request
http.ListenAndServe("localhost:4000", nil)

它将接受所有以"/"开头的请求。我如何限制它只提供 "localhost:4000" 而不是像 "localhost:4000/*" 这样的每个地址？

你们能给我推荐一个好的 Go 教程吗？

Answer 1

您向其注册处理程序的 URL 模式记录在 http.ServeMux 中。输入:

Patterns name fixed, rooted paths, like "/favicon.ico", or rooted subtrees, like "/images/" (note the trailing slash). Longer patterns take precedence over shorter ones, so that if there are handlers registered for both "/images/" and "/images/thumbnails/", the latter handler will be called for paths beginning "/images/thumbnails/" and the former will receive requests for any other paths in the "/images/" subtree.

Note that since a pattern ending in a slash names a rooted subtree, the pattern "/" matches all paths not matched by other registered patterns, not just the URL with Path == "/".

很遗憾，没有只匹配根 ("/") 的模式。

但是你可以很容易地在你的处理程序中检查它，如果请求路径不是根路径，你可以做任何你想做的事情:

func serveRest(w http.ResponseWriter, r *http.Request) {
    if r.URL.Path != "/" {
        w.Write([]byte("Not root!"))
        return
    }
    
    w.Write([]byte("Hi, this is the root!"))
}

如果您想为非根用户返回 HTTP 404 Not found 错误:

func serveRest(w http.ResponseWriter, r *http.Request) {
    if r.URL.Path != "/" {
        http.NotFound(w, r)
        return
    }

    w.Write([]byte("Hi!"))
}

Go 教程:https://tour.golang.org/

另请查看 Go 在此处标记信息，它有一个部分 Go Tutorials。