XMLHttpRequest cannot load http://localhost:3000/signup. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8000' is therefore not allowed access. The response had HTTP status code 403.
package main
import (
"log"
"net/http"
"github.com/gorilla/handlers"
"github.com/gorilla/mux"
"myApp/src/controllers"
)
func main() {
ac := new(controllers.AccountController)
router := mux.NewRouter()
router.HandleFunc("/signup", ac.SignUp).Methods("POST")
router.HandleFunc("/signin", ac.SignIn).Methods("POST")
log.Fatal(http.ListenAndServe(":3000", handlers.CORS()(router)))
}