package main import ( "fmt" "log" "net/http" "os" ) func handler(w http.ResponseWriter, r *http.Request) { target := os.Getenv("TARGET") num, err := strconv.Atoi(target) if err != nil { return "", fmt.Errorf("Failed to parse %s as int! %v", target, err) } logrus.Infof("Checking if %s is prime", target) if num <= 1 { return fmt.Fprintf(w,"%d is not prime", num), nil } for i := 2; i <= int(math.Floor(float64(num)/2)); i++ { if num%i == 0 { return fmt.Fprintf(w,"%d is not prime", num), nil } } return fmt.Fprintf(w,"%d is prime", num), nil } func main() { log.Print("Hello world sample started.") http.HandleFunc("/", handler) port := os.Getenv("PORT") if port == "" { port = "8080" } log.Fatal(http.ListenAndServe(fmt.Sprintf(":%s", port), nil)) }