fix: format IPv6 addr correclty for HTTP URL (#254)

* fix: format IPv6 addr correclty for HTTP URL

* test: cover changes

* test: refactor

---------

Co-authored-by: gm0stache <gm0stache@noreply.codeberg.org>

pkg/client/dns.go

@@ -5,7 +5,9 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
+	"net/netip"
 	"sync"
 	"time"
 
@@ -108,8 +110,7 @@ func verifyCaddyReachable(ctx context.Context, m *pb.MachineInfo) error {
 	eventID := fmt.Sprintf("Machine %s (%s)", m.Name, publicIP)
 	pw.Event(progress.NewEvent(eventID, progress.Working, "Querying"))
 
-	verifyURL := fmt.Sprintf("http://%s%s", publicIP, caddyconfig.VerifyPath)
-
+	verifyURL := getVerifyURL(publicIP)
 	req, err := http.NewRequestWithContext(ctx, http.MethodGet, verifyURL, nil)
 	if err != nil {
 		pw.Event(progress.NewEvent(eventID, progress.Error, err.Error()))
@@ -170,6 +171,11 @@ func verifyCaddyReachable(ctx context.Context, m *pb.MachineInfo) error {
 	}
 }
 
+func getVerifyURL(publicIP netip.Addr) string {
+	httpFormattedIP := net.JoinHostPort(publicIP.String(), "")
+	return fmt.Sprintf("http://%s%s", httpFormattedIP, caddyconfig.VerifyPath)
+}
+
 // unreachable creates a new Unreachable error event.
 func unreachable(id string) progress.Event {
 	return progress.NewEvent(