Serve local files on HTTP (CORS Enabled)

main.go

package main

import (
	"flag"
	"log"
	"net/http"
)

func main() {
	port := flag.String("p", "8100", "port to serve on")
	directory := flag.String("d", ".", "the directory of static file to host")
	flag.Parse()

	fileServer := http.FileServer(http.Dir(*directory))

	http.Handle("/", allowCORS(fileServer))

	log.Printf("Serving %s on HTTP port: %s\n", *directory, *port)
	log.Fatal(http.ListenAndServe(":"+*port, nil))
}

func allowCORS(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Access-Control-Allow-Origin", "*")
		w.Header().Set("Access-Control-Allow-Methods", "*")
		w.Header().Set("Access-Control-Allow-Headers", "*")
		w.Header().Set("Cross-Origin-Opener-Policy", "same-origin")
		w.Header().Set("Cross-Origin-Embedder-Policy", "require-corp")

		if r.Method == http.MethodOptions {
			w.WriteHeader(http.StatusOK)
			return
		}

		next.ServeHTTP(w, r)
	})
}