MAINT: Restructuring of the PowerDNS DSP based on the layout of CSCGlobal (#1549)

* Restructure PowerDNS DSP based on layout for CSCGlobal

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

* Rename api to dsp and make initializer function private

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

Co-authored-by: Tom Limoncelli <tlimoncelli@stackoverflow.com>

providers/powerdns/dns.go

@@ -0,0 +1,146 @@
+package powerdns
+
+import (
+	"context"
+	"github.com/StackExchange/dnscontrol/v3/models"
+	"github.com/StackExchange/dnscontrol/v3/pkg/diff"
+	"github.com/mittwald/go-powerdns/apis/zones"
+	"github.com/mittwald/go-powerdns/pdnshttp"
+	"net/http"
+	"strings"
+)
+
+// GetNameservers returns the nameservers for a domain.
+func (dsp *powerdnsProvider) GetNameservers(string) ([]*models.Nameserver, error) {
+	var r []string
+	for _, j := range dsp.nameservers {
+		r = append(r, j.Name)
+	}
+	return models.ToNameservers(r)
+}
+
+// GetZoneRecords gets the records of a zone and returns them in RecordConfig format.
+func (dsp *powerdnsProvider) GetZoneRecords(domain string) (models.Records, error) {
+	zone, err := dsp.client.Zones().GetZone(context.Background(), dsp.ServerName, domain)
+	if err != nil {
+		return nil, err
+	}
+
+	curRecords := models.Records{}
+	// loop over grouped records by type, called RRSet
+	for _, rrset := range zone.ResourceRecordSets {
+		if rrset.Type == "SOA" {
+			continue
+		}
+		// loop over single records of this group and create records
+		for _, pdnsRecord := range rrset.Records {
+			r, err := toRecordConfig(domain, pdnsRecord, rrset.TTL, rrset.Name, rrset.Type)
+			if err != nil {
+				return nil, err
+			}
+			curRecords = append(curRecords, r)
+		}
+	}
+
+	return curRecords, nil
+}
+
+// GetDomainCorrections returns a list of corrections to update a domain.
+func (dsp *powerdnsProvider) GetDomainCorrections(dc *models.DomainConfig) ([]*models.Correction, error) {
+	var corrections []*models.Correction
+
+	// get current zone records
+	curRecords, err := dsp.GetZoneRecords(dc.Name)
+	if err != nil {
+		return nil, err
+	}
+
+	// post-process records
+	if err := dc.Punycode(); err != nil {
+		return nil, err
+	}
+	models.PostProcessRecords(curRecords)
+
+	// create record diff by group
+	keysToUpdate, err := (diff.New(dc)).ChangedGroups(curRecords)
+	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 := 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
+	corrections = append(corrections, dCorrections...)
+	corrections = append(corrections, cuCorrections...)
+
+	// DNSSec corrections
+	dnssecCorrections, err := dsp.getDNSSECCorrections(dc)
+	if err != nil {
+		return nil, err
+	}
+	corrections = append(corrections, dnssecCorrections...)
+
+	return corrections, nil
+}
+
+// EnsureDomainExists adds a domain to the DNS service if it does not exist
+func (dsp *powerdnsProvider) EnsureDomainExists(domain string) error {
+	if _, err := dsp.client.Zones().GetZone(context.Background(), dsp.ServerName, domain+"."); err != nil {
+		if e, ok := err.(pdnshttp.ErrUnexpectedStatus); ok {
+			if e.StatusCode != http.StatusNotFound {
+				return err
+			}
+		}
+	} else { // domain seems to be there
+		return nil
+	}
+
+	_, err := dsp.client.Zones().CreateZone(context.Background(), dsp.ServerName, zones.Zone{
+		Name:        domain + ".",
+		Type:        zones.ZoneTypeZone,
+		DNSSec:      dsp.DNSSecOnCreate,
+		Nameservers: dsp.DefaultNS,
+	})
+	return err
+}