PowerDNS: Implement diff2 differ and some cleanup (#2194)

Signed-off-by: Jan-Philipp Benecke <jan-philipp@bnck.me>

providers/powerdns/diff.go

@@ -0,0 +1,129 @@
+package powerdns
+
+import (
+	"context"
+	"fmt"
+	"github.com/StackExchange/dnscontrol/v3/models"
+	"github.com/StackExchange/dnscontrol/v3/pkg/diff"
+	"github.com/StackExchange/dnscontrol/v3/pkg/diff2"
+	"github.com/mittwald/go-powerdns/apis/zones"
+	"strings"
+)
+
+func (dsp *powerdnsProvider) getDiff1DomainCorrections(dc *models.DomainConfig, existing models.Records) ([]*models.Correction, error) {
+	// create record diff by group
+	keysToUpdate, err := (diff.New(dc)).ChangedGroups(existing)
+	if err != nil {
+		return nil, err
+	}
+	desiredRecords := dc.Records.GroupedByKey()
+
+	var cuCorrections []*models.Correction
+	var dCorrections []*models.Correction
+
+	// add create/update and delete corrections separately
+	for label, msgs := range keysToUpdate {
+		labelName := canonical(label.NameFQDN)
+		labelType := label.Type
+		msgJoined := strings.Join(msgs, "\n   ")
+
+		if _, ok := desiredRecords[label]; !ok {
+			// no record found so delete it
+			dCorrections = append(dCorrections, &models.Correction{
+				Msg: msgJoined,
+				F: func() error {
+					return dsp.client.Zones().RemoveRecordSetFromZone(context.Background(), dsp.ServerName, dc.Name, labelName, labelType)
+				},
+			})
+		} else {
+			// record found so create or update it
+			ttl := desiredRecords[label][0].TTL
+			var records []zones.Record
+			for _, recordContent := range desiredRecords[label] {
+				records = append(records, zones.Record{
+					Content: recordContent.GetTargetCombined(),
+				})
+			}
+			cuCorrections = append(cuCorrections, &models.Correction{
+				Msg: msgJoined,
+				F: func() error {
+					return dsp.client.Zones().AddRecordSetToZone(context.Background(), dsp.ServerName, dc.Name, zones.ResourceRecordSet{
+						Name:       labelName,
+						Type:       labelType,
+						TTL:        int(ttl),
+						Records:    records,
+						ChangeType: zones.ChangeTypeReplace,
+					})
+				},
+			})
+		}
+	}
+
+	// append corrections in the right order
+	// delete corrections must be run first to avoid correlations with existing RR
+	var corrections []*models.Correction
+	corrections = append(corrections, dCorrections...)
+	corrections = append(corrections, cuCorrections...)
+
+	return corrections, nil
+}
+
+func (dsp *powerdnsProvider) getDiff2DomainCorrections(dc *models.DomainConfig, existing models.Records) ([]*models.Correction, error) {
+	changes, err := diff2.ByRecordSet(existing, dc, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var corrections []*models.Correction
+
+	for _, change := range changes {
+		labelName := canonical(change.Key.NameFQDN)
+		labelType := change.Key.Type
+
+		switch change.Type {
+		case diff2.REPORT:
+			corrections = append(corrections, &models.Correction{Msg: change.MsgsJoined})
+		case diff2.CREATE, diff2.CHANGE:
+			labelTTL := int(change.New[0].TTL)
+			records := buildRecordList(change)
+
+			corrections = append(corrections, &models.Correction{
+				Msg: change.MsgsJoined,
+				F: func() error {
+					return dsp.client.Zones().AddRecordSetToZone(context.Background(), dsp.ServerName, dc.Name, zones.ResourceRecordSet{
+						Name:       labelName,
+						Type:       labelType,
+						TTL:        labelTTL,
+						Records:    records,
+						ChangeType: zones.ChangeTypeReplace,
+					})
+				},
+			})
+		case diff2.DELETE:
+			corrections = append(corrections, &models.Correction{
+				Msg: change.MsgsJoined,
+				F: func() error {
+					return dsp.client.Zones().RemoveRecordSetFromZone(context.Background(), dsp.ServerName, dc.Name, labelName, labelType)
+				},
+			})
+		default:
+			panic(fmt.Sprintf("unhandled change.Type %s", change.Type))
+		}
+	}
+
+	return corrections, nil
+}
+
+// buildRecordList returns a list of records for the PowerDNS resource record set from a change
+func buildRecordList(change diff2.Change) (records []zones.Record) {
+	for _, recordContent := range change.New {
+		records = append(records, zones.Record{
+			Content: recordContent.GetTargetCombined(),
+		})
+	}
+	return
+}
+
+func canonical(fqdn string) string {
+	return fqdn + "."
+}