initial commit

record.go

@@ -0,0 +1,78 @@
+package netboxdns
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+
+	"github.com/doubleu-labs/coredns-netbox-plugin-dns/internal/netbox"
+	"github.com/miekg/dns"
+)
+
+var txtMultiValueRegexp *regexp.Regexp
+
+func init() {
+	txtMultiValueRegexp = regexp.MustCompile(`[^\s"']+|"([^"]*)"|'([^']*)`)
+}
+
+func recordsToRR(records []netbox.Record) ([]dns.RR, error) {
+	out := make([]dns.RR, 0, len(records))
+	for _, record := range records {
+		qtype := dns.StringToType[record.Type]
+		switch qtype {
+		case dns.TypeTXT:
+			out = append(out, recordToTXT(record))
+		default:
+			rrStr := fmt.Sprintf(
+				"%s %d IN %s %s",
+				record.FQDN,
+				*record.TTL,
+				record.Type,
+				record.Value,
+			)
+			rr, err := dns.NewRR(rrStr)
+			if err != nil {
+				return out, err
+			}
+			out = append(out, rr)
+		}
+	}
+	return out, nil
+}
+
+func recordToTXT(record netbox.Record) *dns.TXT {
+	txt := make([]string, 0)
+	if strings.HasPrefix(record.Value, `"`) {
+		values := txtMultiValueRegexp.FindAllString(record.Value, -1)
+		for i := range values {
+			values[i] = strings.Trim(values[i], `"`)
+			values[i] = strings.ReplaceAll(values[i], "\\r\\n", "")
+			values[i] = strings.ReplaceAll(values[i], "\\n", "")
+			values[i] = strings.TrimSpace(values[i])
+			if values[i] != "" {
+				txt = append(txt, values[i])
+			}
+		}
+	} else {
+		txt = append(txt, record.Value)
+	}
+	return &dns.TXT{
+		Hdr: dns.RR_Header{
+			Name:   record.FQDN,
+			Ttl:    *record.TTL,
+			Class:  dns.ClassINET,
+			Rrtype: dns.TypeTXT,
+		},
+		Txt: txt,
+	}
+}
+
+func filterRRByType(rrs []dns.RR, recordType uint16) []dns.RR {
+	out := make([]dns.RR, 0)
+	for _, rr := range rrs {
+		if rr.Header().Rrtype == recordType {
+			out = append(out, rr)
+		}
+	}
+	return out
+}