Earlier in this chapter we talked about using the GUID to act as the URL identifier for all requests. Instead, we started by yielding to the numeric, thus automatically incrementing column in the table. That was for the sake of simplicity, but switching this to the alphanumeric GUID is trivial.

All we'll need to do is to switch our regular expression and change our resulting SQL query in our ServePage handler.

If we only change our regular expression, our last URL's page will still work:

routes.HandleFunc("/page/{id:[0-9a-zA\-]+}", ServePage)

The page will of course still pass through to our handler. To remove any ambiguity, let's assign a guid variable to the route:

routes.HandleFunc("/page/{guid:[0-9a-zA\-]+}", ServePage)

After that, we change our resulting call and SQL:

func ServePage(w http.ResponseWriter, r *http.Request) {
  vars := mux.Vars(r)
  pageGUID := vars["guid"]
  thisPage := Page{}
  fmt.Println(pageGUID)
  err := database.QueryRow("SELECT page_title,page_content,page_date FROM pages WHERE page_guid=?", pageGUID).Scan(&thisPage.Title, &thisPage.Content, &thisPage.Date)

After doing this, accessing our page by the /pages/hello-world URL will result in the same page content we got by accessing it through /pages/1. The only real advantage is cosmetic, it creates a prettier URL that is more human-readable and potentially more useful for search engines: