Merge pull request 'dns: refactor record formatting and sort show results' (#28)

Reviewed-on: #28

pkg/dns/record.go

@@ -6,6 +6,7 @@ import (
 	"io"
 	"net/netip"
 	"sort"
+	"strings"
 	"time"
 
 	"darvaza.org/core"
@@ -38,6 +39,53 @@ func SortAddrRecords(s []AddrRecord) []AddrRecord {
 	return s
 }
 
+// SortRecords sorts a slice of [libdns.Record], by Name, Type and Value
+func SortRecords(s []libdns.Record) []libdns.Record {
+	sort.Slice(s, func(i, j int) bool {
+		return lessRecord(s[i], s[j])
+	})
+	return s
+}
+
+func lessRecord(a, b libdns.Record) bool {
+	aName := strings.ToLower(a.Name)
+	bName := strings.ToLower(b.Name)
+
+	switch {
+	case aName < bName:
+		return true
+	case aName > bName:
+		return false
+	}
+
+	aType := strings.ToUpper(a.Type)
+	bType := strings.ToUpper(b.Type)
+
+	switch {
+	case aType < bType:
+		return true
+	case aType > bType:
+		return false
+	case aType == "A", aType == "AAAA":
+		// IP Addresses
+		var aa, ba netip.Addr
+
+		switch {
+		case aa.UnmarshalText([]byte(a.Value)) != nil:
+			// bad address on a
+			return true
+		case ba.UnmarshalText([]byte(b.Value)) != nil:
+			// bad address on b
+			return false
+		default:
+			return aa.Less(ba)
+		}
+	default:
+		// text
+		return a.Value < b.Value
+	}
+}
+
 // SortRegions sorts regions. first by length those 3-character
 // or shorter, and then by length. It's mostly aimed at
 // supporting ISO-3166 order

pkg/dns/show.go

@@ -1,11 +1,15 @@
 package dns
 
 import (
+	"bytes"
 	"context"
 	"fmt"
+	"io"
+	"os"
 	"time"
 
 	"darvaza.org/core"
+	"github.com/libdns/libdns"
 )
 
 // Show shows current DNS entries
@@ -15,15 +19,40 @@ func (mgr *Manager) Show(ctx context.Context, names ...string) error {
 		return core.Wrap(err, "GetRecords")
 	}
 
+	SortRecords(recs)
+	return writeRecords(recs, os.Stdout)
+}
+
+func writeRecords(recs []libdns.Record, w io.Writer) error {
+	var buf bytes.Buffer
+
 	for _, rr := range recs {
-		_, _ = fmt.Printf("%s\t%v\tIN\t%s\t%s\t; %s\n",
-			rr.Name,
-			int(rr.TTL/time.Second),
-			rr.Type,
-			rr.Value,
-			rr.ID)
+		_ = fmtRecord(&buf, rr)
+		_, _ = buf.WriteRune('\n')
+	}
+	_, _ = fmt.Fprintf(&buf, "; %v records\n", len(recs))
+
+	_, err := buf.WriteTo(w)
+	return err
+}
+
+func fmtRecord(w io.Writer, rr libdns.Record) error {
+	ttl := int(rr.TTL / time.Second)
+	if ttl < 1 {
+		ttl = 1
+	}
+
+	_, err := fmt.Fprintf(w, "%s\t%v\tIN\t%s\t%s",
+		rr.Name,
+		ttl,
+		rr.Type,
+		rr.Value)
+
+	if err == nil {
+		if rr.ID != "" {
+			_, err = fmt.Fprintf(w, "\t; %s", rr.ID)
+		}
 	}
 
-	_, _ = fmt.Printf("; %v records\n", len(recs))
-	return nil
+	return err
 }