package main

import (
  "io"
  "log"
  "net/http"

  "github.com/jub0bs/cors"
)

func main() {
  mux := http.NewServeMux()
  mux.HandleFunc("GET /hello", handleHello) // note: not configured for CORS

  // create CORS middleware
  cors, err := cors.NewMiddleware(cors.Config{
    Origins:        []string{"https://example.com"},
    Methods:        []string{http.MethodGet, http.MethodPost},
    RequestHeaders: []string{"Authorization"},
  })
  if err != nil {
    log.Fatal(err)
  }
  cors.SetDebug(true) // turn debug mode on (optional)

  api := http.NewServeMux()
  api.HandleFunc("GET  /users", handleUsersGet)
  api.HandleFunc("POST /users", handleUsersPost)
  mux.Handle("/api/", http.StripPrefix("/api", cors.Wrap(api))) // note: method-less pattern here

  if err := http.ListenAndServe(":8080", mux); err != http.ErrServerClosed {
    log.Fatal(err)
  }
}

func handleHello(w http.ResponseWriter, _ *http.Request) {
  io.WriteString(w, "Hello, World!")
}

func handleUsersGet(_ http.ResponseWriter, _ *http.Request) {
  // omitted
}

func handleUsersPost(_ http.ResponseWriter, _ *http.Request) {
  // omitted
}