external-dns/provider/azure/azure.go

501 lines
15 KiB
Go

/*
Copyright 2017 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
//nolint:staticcheck // Required due to the current dependency on a deprecated version of azure-sdk-for-go
package azure
import (
"context"
"fmt"
"strings"
"time"
log "github.com/sirupsen/logrus"
azcoreruntime "github.com/Azure/azure-sdk-for-go/sdk/azcore/runtime"
"github.com/Azure/azure-sdk-for-go/sdk/azcore/to"
dns "github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/dns/armdns"
"sigs.k8s.io/external-dns/endpoint"
"sigs.k8s.io/external-dns/plan"
"sigs.k8s.io/external-dns/provider"
)
const (
defaultTTL = 300
)
// ZonesClient is an interface of dns.ZoneClient that can be stubbed for testing.
type ZonesClient interface {
NewListByResourceGroupPager(resourceGroupName string, options *dns.ZonesClientListByResourceGroupOptions) *azcoreruntime.Pager[dns.ZonesClientListByResourceGroupResponse]
}
// RecordSetsClient is an interface of dns.RecordSetsClient that can be stubbed for testing.
type RecordSetsClient interface {
NewListAllByDNSZonePager(resourceGroupName string, zoneName string, options *dns.RecordSetsClientListAllByDNSZoneOptions) *azcoreruntime.Pager[dns.RecordSetsClientListAllByDNSZoneResponse]
Delete(ctx context.Context, resourceGroupName string, zoneName string, relativeRecordSetName string, recordType dns.RecordType, options *dns.RecordSetsClientDeleteOptions) (dns.RecordSetsClientDeleteResponse, error)
CreateOrUpdate(ctx context.Context, resourceGroupName string, zoneName string, relativeRecordSetName string, recordType dns.RecordType, parameters dns.RecordSet, options *dns.RecordSetsClientCreateOrUpdateOptions) (dns.RecordSetsClientCreateOrUpdateResponse, error)
}
// AzureProvider implements the DNS provider for Microsoft's Azure cloud platform.
type AzureProvider struct {
provider.BaseProvider
domainFilter *endpoint.DomainFilter
zoneNameFilter *endpoint.DomainFilter
zoneIDFilter provider.ZoneIDFilter
dryRun bool
resourceGroup string
userAssignedIdentityClientID string
activeDirectoryAuthorityHost string
zonesClient ZonesClient
zonesCache *zonesCache[dns.Zone]
recordSetsClient RecordSetsClient
maxRetriesCount int
}
// NewAzureProvider creates a new Azure provider.
//
// Returns the provider or an error if a provider could not be created.
func NewAzureProvider(configFile string, domainFilter *endpoint.DomainFilter, zoneNameFilter *endpoint.DomainFilter, zoneIDFilter provider.ZoneIDFilter, subscriptionID string, resourceGroup string, userAssignedIdentityClientID string, activeDirectoryAuthorityHost string, zonesCacheDuration time.Duration, maxRetriesCount int, dryRun bool) (*AzureProvider, error) {
cfg, err := getConfig(configFile, subscriptionID, resourceGroup, userAssignedIdentityClientID, activeDirectoryAuthorityHost)
if err != nil {
return nil, fmt.Errorf("failed to read Azure config file '%s': %w", configFile, err)
}
cred, clientOpts, err := getCredentials(*cfg, maxRetriesCount)
if err != nil {
return nil, fmt.Errorf("failed to get credentials: %w", err)
}
zonesClient, err := dns.NewZonesClient(cfg.SubscriptionID, cred, clientOpts)
if err != nil {
return nil, err
}
recordSetsClient, err := dns.NewRecordSetsClient(cfg.SubscriptionID, cred, clientOpts)
if err != nil {
return nil, err
}
return &AzureProvider{
domainFilter: domainFilter,
zoneNameFilter: zoneNameFilter,
zoneIDFilter: zoneIDFilter,
dryRun: dryRun,
resourceGroup: cfg.ResourceGroup,
userAssignedIdentityClientID: cfg.UserAssignedIdentityID,
activeDirectoryAuthorityHost: cfg.ActiveDirectoryAuthorityHost,
zonesClient: zonesClient,
zonesCache: &zonesCache[dns.Zone]{duration: zonesCacheDuration},
recordSetsClient: recordSetsClient,
maxRetriesCount: maxRetriesCount,
}, nil
}
// Records gets the current records.
//
// Returns the current records or an error if the operation failed.
func (p *AzureProvider) Records(ctx context.Context) ([]*endpoint.Endpoint, error) {
zones, err := p.zones(ctx)
if err != nil {
return nil, err
}
endpoints := make([]*endpoint.Endpoint, 0)
for _, zone := range zones {
pager := p.recordSetsClient.NewListAllByDNSZonePager(p.resourceGroup, *zone.Name, &dns.RecordSetsClientListAllByDNSZoneOptions{Top: nil})
for pager.More() {
nextResult, err := pager.NextPage(ctx)
if err != nil {
return nil, provider.NewSoftError(fmt.Errorf("failed to fetch dns records: %w", err))
}
for _, recordSet := range nextResult.Value {
if recordSet.Name == nil || recordSet.Type == nil {
log.Error("Skipping invalid record set with nil name or type.")
continue
}
recordType := strings.TrimPrefix(*recordSet.Type, "Microsoft.Network/dnszones/")
if !p.SupportedRecordType(recordType) {
continue
}
name := formatAzureDNSName(*recordSet.Name, *zone.Name)
if len(p.zoneNameFilter.Filters) > 0 && !p.domainFilter.Match(name) {
log.Debugf("Skipping return of record %s because it was filtered out by the specified --domain-filter", name)
continue
}
targets := extractAzureTargets(recordSet)
if len(targets) == 0 {
log.Debugf("Failed to extract targets for '%s' with type '%s'.", name, recordType)
continue
}
var ttl endpoint.TTL
if recordSet.Properties.TTL != nil {
ttl = endpoint.TTL(*recordSet.Properties.TTL)
}
ep := endpoint.NewEndpointWithTTL(name, recordType, ttl, targets...)
log.Debugf(
"Found %s record for '%s' with target '%s'.",
ep.RecordType,
ep.DNSName,
ep.Targets,
)
endpoints = append(endpoints, ep)
}
}
}
return endpoints, nil
}
// ApplyChanges applies the given changes.
//
// Returns nil if the operation was successful or an error if the operation failed.
func (p *AzureProvider) ApplyChanges(ctx context.Context, changes *plan.Changes) error {
zones, err := p.zones(ctx)
if err != nil {
return err
}
deleted, updated := p.mapChanges(zones, changes)
p.deleteRecords(ctx, deleted)
p.updateRecords(ctx, updated)
return nil
}
func (p *AzureProvider) zones(ctx context.Context) ([]dns.Zone, error) {
log.Debugf("Retrieving Azure DNS zones for resource group: %s.", p.resourceGroup)
if !p.zonesCache.Expired() {
log.Debugf("Using cached Azure DNS zones for resource group: %s zone count: %d.", p.resourceGroup, len(p.zonesCache.Get()))
return p.zonesCache.Get(), nil
}
var zones []dns.Zone
pager := p.zonesClient.NewListByResourceGroupPager(p.resourceGroup, &dns.ZonesClientListByResourceGroupOptions{Top: nil})
for pager.More() {
nextResult, err := pager.NextPage(ctx)
if err != nil {
return nil, err
}
for _, zone := range nextResult.Value {
if zone.Name != nil && p.domainFilter.Match(*zone.Name) && p.zoneIDFilter.Match(*zone.ID) {
zones = append(zones, *zone)
} else if zone.Name != nil && len(p.zoneNameFilter.Filters) > 0 && p.zoneNameFilter.Match(*zone.Name) {
// Handle zoneNameFilter
zones = append(zones, *zone)
}
}
}
log.Debugf("Found %d Azure DNS zone(s). Updating zones cache", len(zones))
p.zonesCache.Reset(zones)
return zones, nil
}
func (p *AzureProvider) SupportedRecordType(recordType string) bool {
switch recordType {
case "MX":
return true
default:
return provider.SupportedRecordType(recordType)
}
}
type azureChangeMap map[string][]*endpoint.Endpoint
func (p *AzureProvider) mapChanges(zones []dns.Zone, changes *plan.Changes) (azureChangeMap, azureChangeMap) {
ignored := map[string]bool{}
deleted := azureChangeMap{}
updated := azureChangeMap{}
zoneNameIDMapper := provider.ZoneIDName{}
for _, z := range zones {
if z.Name != nil {
zoneNameIDMapper.Add(*z.Name, *z.Name)
}
}
mapChange := func(changeMap azureChangeMap, change *endpoint.Endpoint) {
zone, _ := zoneNameIDMapper.FindZone(change.DNSName)
if zone == "" {
if _, ok := ignored[change.DNSName]; !ok {
ignored[change.DNSName] = true
log.Infof("Ignoring changes to '%s' because a suitable Azure DNS zone was not found.", change.DNSName)
}
return
}
// Ensure the record type is suitable
changeMap[zone] = append(changeMap[zone], change)
}
for _, change := range changes.Delete {
mapChange(deleted, change)
}
for _, change := range changes.Create {
mapChange(updated, change)
}
for _, change := range changes.UpdateNew() {
mapChange(updated, change)
}
return deleted, updated
}
func (p *AzureProvider) deleteRecords(ctx context.Context, deleted azureChangeMap) {
// Delete records first
for zone, endpoints := range deleted {
for _, ep := range endpoints {
name := p.recordSetNameForZone(zone, ep)
if !p.domainFilter.Match(ep.DNSName) {
log.Debugf("Skipping deletion of record %s because it was filtered out by the specified --domain-filter", ep.DNSName)
continue
}
if p.dryRun {
log.Infof("Would delete %s record named '%s' for Azure DNS zone '%s'.", ep.RecordType, name, zone)
} else {
log.Infof("Deleting %s record named '%s' for Azure DNS zone '%s'.", ep.RecordType, name, zone)
if _, err := p.recordSetsClient.Delete(ctx, p.resourceGroup, zone, name, dns.RecordType(ep.RecordType), nil); err != nil {
log.Errorf(
"Failed to delete %s record named '%s' for Azure DNS zone '%s': %v",
ep.RecordType,
name,
zone,
err,
)
}
}
}
}
}
func (p *AzureProvider) updateRecords(ctx context.Context, updated azureChangeMap) {
for zone, endpoints := range updated {
for _, ep := range endpoints {
name := p.recordSetNameForZone(zone, ep)
if !p.domainFilter.Match(ep.DNSName) {
log.Debugf("Skipping update of record %s because it was filtered out by the specified --domain-filter", ep.DNSName)
continue
}
if p.dryRun {
log.Infof(
"Would update %s record named '%s' to '%s' for Azure DNS zone '%s'.",
ep.RecordType,
name,
ep.Targets,
zone,
)
continue
}
log.Infof(
"Updating %s record named '%s' to '%s' for Azure DNS zone '%s'.",
ep.RecordType,
name,
ep.Targets,
zone,
)
recordSet, err := p.newRecordSet(ep)
if err == nil {
_, err = p.recordSetsClient.CreateOrUpdate(
ctx,
p.resourceGroup,
zone,
name,
dns.RecordType(ep.RecordType),
recordSet,
nil,
)
}
if err != nil {
log.Errorf(
"Failed to update %s record named '%s' to '%s' for DNS zone '%s': %v",
ep.RecordType,
name,
ep.Targets,
zone,
err,
)
}
}
}
}
func (p *AzureProvider) recordSetNameForZone(zone string, endpoint *endpoint.Endpoint) string {
// Remove the zone from the record set
name := endpoint.DNSName
name = name[:len(name)-len(zone)]
name = strings.TrimSuffix(name, ".")
// For root, use @
if name == "" {
return "@"
}
return name
}
func (p *AzureProvider) newRecordSet(endpoint *endpoint.Endpoint) (dns.RecordSet, error) {
var ttl int64 = defaultTTL
if endpoint.RecordTTL.IsConfigured() {
ttl = int64(endpoint.RecordTTL)
}
switch dns.RecordType(endpoint.RecordType) {
case dns.RecordTypeA:
aRecords := make([]*dns.ARecord, len(endpoint.Targets))
for i, target := range endpoint.Targets {
aRecords[i] = &dns.ARecord{
IPv4Address: to.Ptr(target),
}
}
return dns.RecordSet{
Properties: &dns.RecordSetProperties{
TTL: to.Ptr(ttl),
ARecords: aRecords,
},
}, nil
case dns.RecordTypeAAAA:
aaaaRecords := make([]*dns.AaaaRecord, len(endpoint.Targets))
for i, target := range endpoint.Targets {
aaaaRecords[i] = &dns.AaaaRecord{
IPv6Address: to.Ptr(target),
}
}
return dns.RecordSet{
Properties: &dns.RecordSetProperties{
TTL: to.Ptr(ttl),
AaaaRecords: aaaaRecords,
},
}, nil
case dns.RecordTypeCNAME:
return dns.RecordSet{
Properties: &dns.RecordSetProperties{
TTL: to.Ptr(ttl),
CnameRecord: &dns.CnameRecord{
Cname: to.Ptr(endpoint.Targets[0]),
},
},
}, nil
case dns.RecordTypeMX:
mxRecords := make([]*dns.MxRecord, len(endpoint.Targets))
for i, target := range endpoint.Targets {
mxRecord, err := parseMxTarget[dns.MxRecord](target)
if err != nil {
return dns.RecordSet{}, err
}
mxRecords[i] = &mxRecord
}
return dns.RecordSet{
Properties: &dns.RecordSetProperties{
TTL: to.Ptr(ttl),
MxRecords: mxRecords,
},
}, nil
case dns.RecordTypeNS:
nsRecords := make([]*dns.NsRecord, len(endpoint.Targets))
for i, target := range endpoint.Targets {
nsRecords[i] = &dns.NsRecord{
Nsdname: to.Ptr(target),
}
}
return dns.RecordSet{
Properties: &dns.RecordSetProperties{
TTL: to.Ptr(ttl),
NsRecords: nsRecords,
},
}, nil
case dns.RecordTypeTXT:
return dns.RecordSet{
Properties: &dns.RecordSetProperties{
TTL: to.Ptr(ttl),
TxtRecords: []*dns.TxtRecord{
{
Value: []*string{
&endpoint.Targets[0],
},
},
},
},
}, nil
}
return dns.RecordSet{}, fmt.Errorf("unsupported record type '%s'", endpoint.RecordType)
}
// Helper function (shared with test code)
func formatAzureDNSName(recordName, zoneName string) string {
if recordName == "@" {
return zoneName
}
return fmt.Sprintf("%s.%s", recordName, zoneName)
}
// Helper function (shared with text code)
func extractAzureTargets(recordSet *dns.RecordSet) []string {
properties := recordSet.Properties
if properties == nil {
return []string{}
}
// Check for A records
aRecords := properties.ARecords
if len(aRecords) > 0 && (aRecords)[0].IPv4Address != nil {
targets := make([]string, len(aRecords))
for i, aRecord := range aRecords {
targets[i] = *aRecord.IPv4Address
}
return targets
}
// Check for AAAA records
aaaaRecords := properties.AaaaRecords
if len(aaaaRecords) > 0 && (aaaaRecords)[0].IPv6Address != nil {
targets := make([]string, len(aaaaRecords))
for i, aaaaRecord := range aaaaRecords {
targets[i] = *aaaaRecord.IPv6Address
}
return targets
}
// Check for CNAME records
cnameRecord := properties.CnameRecord
if cnameRecord != nil && cnameRecord.Cname != nil {
return []string{*cnameRecord.Cname}
}
// Check for MX records
mxRecords := properties.MxRecords
if len(mxRecords) > 0 && (mxRecords)[0].Exchange != nil {
targets := make([]string, len(mxRecords))
for i, mxRecord := range mxRecords {
targets[i] = fmt.Sprintf("%d %s", *mxRecord.Preference, *mxRecord.Exchange)
}
return targets
}
// Check for NS records
nsRecords := properties.NsRecords
if len(nsRecords) > 0 && (nsRecords)[0].Nsdname != nil {
targets := make([]string, len(nsRecords))
for i, nsRecord := range nsRecords {
targets[i] = *nsRecord.Nsdname
}
return targets
}
// Check for TXT records
txtRecords := properties.TxtRecords
if len(txtRecords) > 0 && (txtRecords)[0].Value != nil {
values := (txtRecords)[0].Value
if len(values) > 0 {
return []string{*(values)[0]}
}
}
return []string{}
}