jpictl/dns: introduce add command to register new machines

Signed-off-by: Alejandro Mery <amery@jpi.io>

pkg/dns/add.go

@@ -0,0 +1,67 @@
+package dns
+
+import (
+	"context"
+	"net/netip"
+	"os"
+	"time"
+
+	"darvaza.org/core"
+	"github.com/libdns/libdns"
+)
+
+// Add adds a machine to the DNS records
+func (mgr *Manager) Add(ctx context.Context, name string, addrs ...netip.Addr) error {
+	// TODO: validate name
+
+	cur, err := mgr.GetRecords(ctx, name)
+	if err != nil {
+		return core.Wrap(err, "GetRecords")
+	}
+
+	// merge []SyncAddr for name
+	s := mgr.asSyncRecordsMap(cur)[name+mgr.suffix]
+	for _, addr := range addrs {
+		s = AppendSyncAddr(s, addr)
+	}
+
+	return mgr.addSyncAddr(ctx, name, s)
+}
+
+func (mgr *Manager) addSyncAddr(ctx context.Context, name string, s []SyncAddr) error {
+	var recs []libdns.Record
+
+	for _, a := range s {
+		recs = append(recs, libdns.Record{
+			ID:    a.ID,
+			Name:  name + mgr.suffix,
+			Type:  core.IIf(a.Addr.Is6(), "AAAA", "A"),
+			TTL:   time.Second,
+			Value: a.Addr.String(),
+		})
+	}
+
+	SortRecords(recs)
+	err := writeRecords(recs, os.Stdout)
+	if err != nil {
+		return err
+	}
+
+	_, err = mgr.p.SetRecords(ctx, mgr.domain, recs)
+	return err
+}
+
+func AppendSyncAddr(s []SyncAddr, addr netip.Addr) []SyncAddr {
+	for _, se := range s {
+		if se.Addr.Compare(addr) == 0 {
+			// found
+			return s
+		}
+	}
+
+	s = append(s, SyncAddr{
+		Addr: addr,
+		TTL:  time.Second,
+	})
+	return s
+}