Logging handler processing time in Go

main.go

package main

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

// Some handlers here

func DefaultWrapper(handler http.Handler) http.Handler {  
   return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
      start := time.Now()
      handler.ServeHTTP(w, r)
      log.Printf("%s %s %s %s", r.RemoteAddr, time.Since(start), r.Method, r.URL)
   })
}

func main() {  
   router := mux.NewRouter().StrictSlash(true)
   router.HandleFunc("/api/something", SomethingIndexHandler).Methods("GET")
   router.HandleFunc("/api/something", SomethingCreateHandler).Methods("POST")

   port := ":9000"
   log.Printf("Starting web server on " + port)
   err := http.ListenAndServe(port, DefaultWrapper(router))
   if err != nil {
      log.Fatal(err)
   }
}