golang gorilla mux sub/router + specific middleware per subrouter

main.go

package main

import (
	"time"
	"fmt"
	"net/http"
	"github.com/gorilla/mux"
)

func main() {
  router := mux.NewRouter()

  router.Use(middleware1)

  wsRouter := router.PathPrefix("/ws").Subrouter()
  wsRouter.Use(middleware2)
  wsRouter.Use(middleware3)

  wsRouter.HandleFunc("/sub", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    fmt.Println("handling ws /sub")
    w.Write([]byte("/sub (ws)"))
  }))

  chainRouter := router.PathPrefix("/chain").Subrouter()
  chainRouter.HandleFunc("/sub1", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    fmt.Println("handling chain /sub1")
    w.Write([]byte("/sub1"))
  }))
  chainRouter.HandleFunc("/sub2", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    fmt.Println("handling chain /sub2")
    w.Write([]byte("/sub2"))
  }))

  restRouter := router.PathPrefix("/").Subrouter()
  restRouter.Use(middleware3)

  restRouter.HandleFunc("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    fmt.Println("handling rest /")
    w.Write([]byte("/ (rest)"))
  }))

  server := &http.Server{
        Addr:         "0.0.0.0:8080",
        // Good practice to set timeouts to avoid Slowloris attacks.
        WriteTimeout: time.Second * 15,
        ReadTimeout:  time.Second * 15,
        IdleTimeout:  time.Second * 60,
        Handler: router, // Pass our instance of gorilla/mux in.
    }

  fmt.Println("starting server")
  if err := server.ListenAndServe(); err != nil {
    fmt.Println(err)
  }
}

func middleware1(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		fmt.Println("middleware1")
		next.ServeHTTP(w, r)
	})
}

func middleware2(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		fmt.Println("middleware2")
		next.ServeHTTP(w, r)
	})
}

func middleware3(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		fmt.Println("middleware3")
		next.ServeHTTP(w, r)
	})
}