How do I get the URL before routing? - go

Question

I want to get the url or the neme of the route before routing it, ex:
router.HandleFunc("/person", person.HandlePerson)
router.HandleFunc("/animal", animal.HandleAnimal)
I want to know the route before routing like this:
nameOfRoute:= //I want this variable to store the name of the route (person or animal) before routing
fmt.Println(nameOfRoute) //This line will print the name of the route ("/animal", "/person")
router.HandleFunc("/person", person.HandlePerson)
router.HandleFunc("/animal", animal.HandleAnimal)
How can I do this in Golang

Answer 1

You cannot — in the sense that you showed. That's because the statements
router.HandleFunc("/person", person.HandlePerson)
are not actions which carry out actual routing but rather directives to the router about how it should do routing.
The routing itself is handler via a single "entry" function of your router.
What you can do, however, is to employ "cascading" of several routers:
Create a router which handles /, and then create another router which handles all your indiviual routes — as it's currently done.
Make the sole handler function of the first — root — router print the URL and then merely call the inner's router entry function.
I have no idea which router package are you using (there are gazillions of them, including the stock one) so I cannot tell you what that function is; in a stock router it's ServeHTTP.
Please consider figuring this out as a homework ;-)
With a stock net/http's ServeMux, you do not even need a root router because a single function would do — something like this:
mux := http.NewServeMux()
mux.Handle("/person", whatever)
...
server := http.Server{
Handler: func(w http.ResponseWriter, r *http.Request) {
fmt.Println(r.URL)
mux.ServeHTTP(w, r)
},
}
server.ListenAndServe()