fix: look up ipv4 from host correctly

We use a custom resolver now instead of relying on the baked-in
Golang resolver which has issues. We use a friendly librehoster
DNS resolver and not Google because fuck that.

cli/server/init.go

@@ -5,11 +5,13 @@ import (
 	"errors"
 	"fmt"
 	"net"
+	"time"
 
 	"coopcloud.tech/abra/cli/internal"
 	"coopcloud.tech/abra/client"
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/swarm"
+	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
 )
 
@@ -36,20 +38,31 @@ later for more advanced use cases.
 			return err
 		}
 
-		var ipv4 net.IP
-		ips, _ := net.LookupIP(host)
-		for _, ip := range ips {
-			ipv4 = ip.To4()
-		}
-
-		if string(ipv4) == "" {
-			return fmt.Errorf("unable to retrieve ipv4 address for %s", host)
+		resolver := &net.Resolver{
+			PreferGo: false,
+			Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
+				d := net.Dialer{
+					Timeout: time.Millisecond * time.Duration(10000),
+				}
+				// comrade librehosters DNS resolver https://snopyta.org/service/dns/
+				return d.DialContext(ctx, "udp", "95.216.24.230:53")
+			},
 		}
 
 		ctx := context.Background()
+		ips, err := resolver.LookupIPAddr(ctx, host)
+		if err != nil {
+			logrus.Fatal(err)
+		}
+
+		if len(ips) == 0 {
+			return fmt.Errorf("unable to retrieve ipv4 address for %s", host)
+		}
+		ipv4 := ips[0].IP.To4().String()
+
 		initReq := swarm.InitRequest{
 			ListenAddr:    "0.0.0.0:2377",
-			AdvertiseAddr: string(ipv4),
+			AdvertiseAddr: ipv4,
 		}
 		if _, err := cl.SwarmInit(ctx, initReq); err != nil {
 			return err