gowasep - its like wasap.my, but built using go - demo at wasep.mirul.xyz

main.go

package main

import (
	"flag"
	"fmt"
	"net/http"
	"regexp"
)

var phoneNumberLink = regexp.MustCompile(`^/\+?\d+$`)

func handlerFunc(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "text/html")

	if r.URL.Path == "/" {
		fmt.Fprint(w, "<h1>Welcome to Wasep</h1>"+
			"<p>Add your phone number at the back of this link</p>")

	} else if phoneNumberLink.MatchString(r.URL.Path) {
		re := regexp.MustCompile(`\+?\d+$`)
		phoneNumber := fmt.Sprintf("%s", re.FindAllString(r.URL.Path, 1)[0])
		wasepURL := "https://api.whatsapp.com/send?phone=" + phoneNumber
		fmt.Println(phoneNumber, wasepURL)
		http.Redirect(w, r, wasepURL, 302)

	} else {
		http.Error(w, "<h1>404 Error</h1>"+
			"<p>Cannot find the page you were looking for</p>", http.StatusNotFound)
	}
}

func main() {
	var port = flag.Int("port", 3003, "Port to use [3003]")
	flag.Parse()

	fmt.Println("Serving at port", *port)
	http.ListenAndServe(fmt.Sprintf(":%d", *port), http.HandlerFunc(handlerFunc))
}