std net/http is enough PI

std-http-PI.go

package main

import (
	"fmt"
	"net/http"
	"strings"
)

func main() {

	mux := http.NewServeMux()
	mux.HandleFunc("/user/", userHandler) // to handle /user/:id

	http.ListenAndServe(":8080", mux)
}

func userHandler(w http.ResponseWriter, r *http.Request) {

	//
	// we need to handle the following:
	// /user/:id
	//
	// I'm not converting :id to integer or GUID...
	//

	param := r.URL.Path[6:]

	idx := strings.Index(param, "/")
	if idx == -1 {

		// url /user/:id we're all set
		fmt.Fprintf(w, "/user/:id id=%s", param)
		return
	}

	static := param[idx+1:]

	// found slash but no more to the URL
	if len(static) == 0 {
		http.Redirect(w, r, r.URL.Path[:len(r.URL.Path)-1], http.StatusMovedPermanently)
		return
	}

	http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)
}