Merge pull request #4346 from khuedoan/az-private-dns-zone-name-filter

feat(azure): add zone name filter for Azure Private DNS
kubernetes-sigs · Apr 25, 2024 · c506a20 · c506a20
2 parents c006a49 + b16d1b3
commit c506a20
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Showing 5 changed files with 160 additions and 9 deletions.
diff --git a/docs/tutorials/azure-private-dns.md b/docs/tutorials/azure-private-dns.md
@@ -430,7 +430,13 @@ spec:
         pathType: Prefix
 ```
 
-When using ExternalDNS with ingress objects it will automatically create DNS records based on host names specified in ingress objects that match the domain-filter argument in the externaldns deployment manifest. When those host names are removed or renamed the corresponding DNS records are also altered.
+When you use ExternalDNS with Ingress resources, it automatically creates DNS records based on the hostnames listed in those Ingress objects.
+Those hostnames must match the filters that you defined (if any):
+
+- By default, `--domain-filter` filters Azure Private DNS zone.
+- If you use `--domain-filter` together with `--zone-name-filter`, the behavior changes: `--domain-filter` then filters Ingress domains, not the Azure Private DNS zone name.
+
+When those hostnames are removed or renamed the corresponding DNS records are also altered.
 
 Create the deployment, service and ingress object:
 

diff --git a/docs/tutorials/azure.md b/docs/tutorials/azure.md
@@ -737,7 +737,13 @@ spec:
                   number: 80
 ```
 
-When using ExternalDNS with `ingress` objects it will automatically create DNS records based on host names specified in ingress objects that match the domain-filter argument in the external-dns deployment manifest. When those host names are removed or renamed the corresponding DNS records are also altered.
+When you use ExternalDNS with Ingress resources, it automatically creates DNS records based on the hostnames listed in those Ingress objects.
+Those hostnames must match the filters that you defined (if any):
+
+- By default, `--domain-filter` filters Azure DNS zone.
+- If you use `--domain-filter` together with `--zone-name-filter`, the behavior changes: `--domain-filter` then filters Ingress domains, not the Azure DNS zone name.
+
+When those hostnames are removed or renamed the corresponding DNS records are also altered.
 
 Create the deployment, service and ingress object:
 

diff --git a/main.go b/main.go
@@ -255,7 +255,7 @@ func main() {
 	case "azure-dns", "azure":
 		p, err = azure.NewAzureProvider(cfg.AzureConfigFile, domainFilter, zoneNameFilter, zoneIDFilter, cfg.AzureSubscriptionID, cfg.AzureResourceGroup, cfg.AzureUserAssignedIdentityClientID, cfg.AzureActiveDirectoryAuthorityHost, cfg.DryRun)
 	case "azure-private-dns":
-		p, err = azure.NewAzurePrivateDNSProvider(cfg.AzureConfigFile, domainFilter, zoneIDFilter, cfg.AzureSubscriptionID, cfg.AzureResourceGroup, cfg.AzureUserAssignedIdentityClientID, cfg.AzureActiveDirectoryAuthorityHost, cfg.DryRun)
+		p, err = azure.NewAzurePrivateDNSProvider(cfg.AzureConfigFile, domainFilter, zoneNameFilter, zoneIDFilter, cfg.AzureSubscriptionID, cfg.AzureResourceGroup, cfg.AzureUserAssignedIdentityClientID, cfg.AzureActiveDirectoryAuthorityHost, cfg.DryRun)
 	case "bluecat":
 		p, err = bluecat.NewBluecatProvider(cfg.BluecatConfigFile, cfg.BluecatDNSConfiguration, cfg.BluecatDNSServerName, cfg.BluecatDNSDeployType, cfg.BluecatDNSView, cfg.BluecatGatewayHost, cfg.BluecatRootZone, cfg.TXTPrefix, cfg.TXTSuffix, domainFilter, zoneIDFilter, cfg.DryRun, cfg.BluecatSkipTLSVerify)
 	case "vinyldns":

diff --git a/provider/azure/azure_private_dns.go b/provider/azure/azure_private_dns.go
@@ -48,6 +48,7 @@ type PrivateRecordSetsClient interface {
 type AzurePrivateDNSProvider struct {
 	provider.BaseProvider
 	domainFilter                 endpoint.DomainFilter
+	zoneNameFilter               endpoint.DomainFilter
 	zoneIDFilter                 provider.ZoneIDFilter
 	dryRun                       bool
 	resourceGroup                string
@@ -60,7 +61,7 @@ type AzurePrivateDNSProvider struct {
 // NewAzurePrivateDNSProvider creates a new Azure Private DNS provider.
 //
 // Returns the provider or an error if a provider could not be created.
-func NewAzurePrivateDNSProvider(configFile string, domainFilter endpoint.DomainFilter, zoneIDFilter provider.ZoneIDFilter, subscriptionID string, resourceGroup string, userAssignedIdentityClientID string, activeDirectoryAuthorityHost string, dryRun bool) (*AzurePrivateDNSProvider, error) {
+func NewAzurePrivateDNSProvider(configFile string, domainFilter endpoint.DomainFilter, zoneNameFilter endpoint.DomainFilter, zoneIDFilter provider.ZoneIDFilter, subscriptionID string, resourceGroup string, userAssignedIdentityClientID string, activeDirectoryAuthorityHost string, dryRun bool) (*AzurePrivateDNSProvider, error) {
 	cfg, err := getConfig(configFile, subscriptionID, resourceGroup, userAssignedIdentityClientID, activeDirectoryAuthorityHost)
 	if err != nil {
 		return nil, fmt.Errorf("failed to read Azure config file '%s': %v", configFile, err)
@@ -80,6 +81,7 @@ func NewAzurePrivateDNSProvider(configFile string, domainFilter endpoint.DomainF
 	}
 	return &AzurePrivateDNSProvider{
 		domainFilter:                 domainFilter,
+		zoneNameFilter:               zoneNameFilter,
 		zoneIDFilter:                 zoneIDFilter,
 		dryRun:                       dryRun,
 		resourceGroup:                cfg.ResourceGroup,
@@ -124,6 +126,10 @@ func (p *AzurePrivateDNSProvider) Records(ctx context.Context) (endpoints []*end
 				}
 				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 := extractAzurePrivateDNSTargets(recordSet)
 				if len(targets) == 0 {
 					log.Debugf("Failed to extract targets for '%s' with type '%s'.", name, recordType)
@@ -185,6 +191,9 @@ func (p *AzurePrivateDNSProvider) zones(ctx context.Context) ([]privatedns.Priva
 
 			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)
 			}
 		}
 	}
@@ -238,6 +247,10 @@ func (p *AzurePrivateDNSProvider) deleteRecords(ctx context.Context, deleted azu
 	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 Private DNS zone '%s'.", ep.RecordType, name, zone)
 			} else {
@@ -261,6 +274,10 @@ func (p *AzurePrivateDNSProvider) updateRecords(ctx context.Context, updated azu
 	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 Private DNS zone '%s'.",

diff --git a/provider/azure/azure_privatedns_test.go b/provider/azure/azure_privatedns_test.go
@@ -224,15 +224,16 @@ func createPrivateMockRecordSetMultiWithTTL(name, recordType string, ttl int64,
 }
 
 // newMockedAzurePrivateDNSProvider creates an AzureProvider comprising the mocked clients for zones and recordsets
-func newMockedAzurePrivateDNSProvider(domainFilter endpoint.DomainFilter, zoneIDFilter provider.ZoneIDFilter, dryRun bool, resourceGroup string, zones []*privatedns.PrivateZone, recordSets []*privatedns.RecordSet) (*AzurePrivateDNSProvider, error) {
+func newMockedAzurePrivateDNSProvider(domainFilter endpoint.DomainFilter, zoneNameFilter endpoint.DomainFilter, zoneIDFilter provider.ZoneIDFilter, dryRun bool, resourceGroup string, zones []*privatedns.PrivateZone, recordSets []*privatedns.RecordSet) (*AzurePrivateDNSProvider, error) {
 	zonesClient := newMockPrivateZonesClient(zones)
 	recordSetsClient := newMockPrivateRecordSectsClient(recordSets)
-	return newAzurePrivateDNSProvider(domainFilter, zoneIDFilter, dryRun, resourceGroup, &zonesClient, &recordSetsClient), nil
+	return newAzurePrivateDNSProvider(domainFilter, zoneNameFilter, zoneIDFilter, dryRun, resourceGroup, &zonesClient, &recordSetsClient), nil
 }
 
-func newAzurePrivateDNSProvider(domainFilter endpoint.DomainFilter, zoneIDFilter provider.ZoneIDFilter, dryRun bool, resourceGroup string, privateZonesClient PrivateZonesClient, privateRecordsClient PrivateRecordSetsClient) *AzurePrivateDNSProvider {
+func newAzurePrivateDNSProvider(domainFilter endpoint.DomainFilter, zoneNameFilter endpoint.DomainFilter, zoneIDFilter provider.ZoneIDFilter, dryRun bool, resourceGroup string, privateZonesClient PrivateZonesClient, privateRecordsClient PrivateRecordSetsClient) *AzurePrivateDNSProvider {
 	return &AzurePrivateDNSProvider{
 		domainFilter:     domainFilter,
+		zoneNameFilter:   zoneNameFilter,
 		zoneIDFilter:     zoneIDFilter,
 		dryRun:           dryRun,
 		resourceGroup:    resourceGroup,
@@ -242,7 +243,7 @@ func newAzurePrivateDNSProvider(domainFilter endpoint.DomainFilter, zoneIDFilter
 }
 
 func TestAzurePrivateDNSRecord(t *testing.T) {
-	provider, err := newMockedAzurePrivateDNSProvider(endpoint.NewDomainFilter([]string{"example.com"}), provider.NewZoneIDFilter([]string{""}), true, "k8s",
+	provider, err := newMockedAzurePrivateDNSProvider(endpoint.NewDomainFilter([]string{"example.com"}), endpoint.NewDomainFilter([]string{}), provider.NewZoneIDFilter([]string{""}), true, "k8s",
 		[]*privatedns.PrivateZone{
 			createMockPrivateZone("example.com", "/privateDnsZones/example.com"),
 		},
@@ -281,7 +282,7 @@ func TestAzurePrivateDNSRecord(t *testing.T) {
 }
 
 func TestAzurePrivateDNSMultiRecord(t *testing.T) {
-	provider, err := newMockedAzurePrivateDNSProvider(endpoint.NewDomainFilter([]string{"example.com"}), provider.NewZoneIDFilter([]string{""}), true, "k8s",
+	provider, err := newMockedAzurePrivateDNSProvider(endpoint.NewDomainFilter([]string{"example.com"}), endpoint.NewDomainFilter([]string{}), provider.NewZoneIDFilter([]string{""}), true, "k8s",
 		[]*privatedns.PrivateZone{
 			createMockPrivateZone("example.com", "/privateDnsZones/example.com"),
 		},
@@ -369,6 +370,7 @@ func testAzurePrivateDNSApplyChangesInternal(t *testing.T, dryRun bool, client P
 	zonesClient := newMockPrivateZonesClient(zones)
 
 	provider := newAzurePrivateDNSProvider(
+		endpoint.NewDomainFilter([]string{""}),
 		endpoint.NewDomainFilter([]string{""}),
 		provider.NewZoneIDFilter([]string{""}),
 		dryRun,
@@ -430,3 +432,123 @@ func testAzurePrivateDNSApplyChangesInternal(t *testing.T, dryRun bool, client P
 		t.Fatal(err)
 	}
 }
+
+func TestAzurePrivateDNSNameFilter(t *testing.T) {
+	provider, err := newMockedAzurePrivateDNSProvider(endpoint.NewDomainFilter([]string{"nginx.example.com"}), endpoint.NewDomainFilter([]string{"example.com"}), provider.NewZoneIDFilter([]string{""}), true, "k8s",
+		[]*privatedns.PrivateZone{
+			createMockPrivateZone("example.com", "/privateDnsZones/example.com"),
+		},
+
+		[]*privatedns.RecordSet{
+			createPrivateMockRecordSet("@", "NS", "ns1-03.azure-dns.com."),
+			createPrivateMockRecordSet("@", "SOA", "Email: azuredns-hostmaster.microsoft.com"),
+			createPrivateMockRecordSet("@", endpoint.RecordTypeA, "123.123.123.122"),
+			createPrivateMockRecordSet("@", endpoint.RecordTypeTXT, "heritage=external-dns,external-dns/owner=default"),
+			createPrivateMockRecordSetWithTTL("test.nginx", endpoint.RecordTypeA, "123.123.123.123", 3600),
+			createPrivateMockRecordSetWithTTL("nginx", endpoint.RecordTypeA, "123.123.123.123", 3600),
+			createPrivateMockRecordSetWithTTL("nginx", endpoint.RecordTypeTXT, "heritage=external-dns,external-dns/owner=default", recordTTL),
+			createPrivateMockRecordSetWithTTL("mail.nginx", endpoint.RecordTypeMX, "20 example.com", recordTTL),
+			createPrivateMockRecordSetWithTTL("hack", endpoint.RecordTypeCNAME, "hack.azurewebsites.net", 10),
+		})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ctx := context.Background()
+	actual, err := provider.Records(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	expected := []*endpoint.Endpoint{
+		endpoint.NewEndpointWithTTL("test.nginx.example.com", endpoint.RecordTypeA, 3600, "123.123.123.123"),
+		endpoint.NewEndpointWithTTL("nginx.example.com", endpoint.RecordTypeA, 3600, "123.123.123.123"),
+		endpoint.NewEndpointWithTTL("nginx.example.com", endpoint.RecordTypeTXT, recordTTL, "heritage=external-dns,external-dns/owner=default"),
+		endpoint.NewEndpointWithTTL("mail.nginx.example.com", endpoint.RecordTypeMX, recordTTL, "20 example.com"),
+	}
+
+	validateAzureEndpoints(t, actual, expected)
+}
+
+func TestAzurePrivateDNSApplyChangesZoneName(t *testing.T) {
+	recordsClient := mockRecordSetsClient{}
+
+	testAzureApplyChangesInternalZoneName(t, false, &recordsClient)
+
+	validateAzureEndpoints(t, recordsClient.deletedEndpoints, []*endpoint.Endpoint{
+		endpoint.NewEndpoint("deleted.foo.example.com", endpoint.RecordTypeA, ""),
+		endpoint.NewEndpoint("deletedaaaa.foo.example.com", endpoint.RecordTypeAAAA, ""),
+		endpoint.NewEndpoint("deletedcname.foo.example.com", endpoint.RecordTypeCNAME, ""),
+	})
+
+	validateAzureEndpoints(t, recordsClient.updatedEndpoints, []*endpoint.Endpoint{
+		endpoint.NewEndpointWithTTL("foo.example.com", endpoint.RecordTypeA, endpoint.TTL(recordTTL), "1.2.3.4", "1.2.3.5"),
+		endpoint.NewEndpointWithTTL("foo.example.com", endpoint.RecordTypeAAAA, endpoint.TTL(recordTTL), "2001::1:2:3:4", "2001::1:2:3:5"),
+		endpoint.NewEndpointWithTTL("foo.example.com", endpoint.RecordTypeTXT, endpoint.TTL(recordTTL), "tag"),
+		endpoint.NewEndpointWithTTL("new.foo.example.com", endpoint.RecordTypeA, 3600, "111.222.111.222"),
+		endpoint.NewEndpointWithTTL("new.foo.example.com", endpoint.RecordTypeAAAA, 3600, "2001::111:222:111:222"),
+		endpoint.NewEndpointWithTTL("newcname.foo.example.com", endpoint.RecordTypeCNAME, 10, "other.com"),
+	})
+}
+
+func testAzurePrivateDNSApplyChangesInternalZoneName(t *testing.T, dryRun bool, client PrivateRecordSetsClient) {
+	zones := []*privatedns.PrivateZone{
+		createMockPrivateZone("example.com", "/privateDnsZones/example.com"),
+	}
+	zonesClient := newMockPrivateZonesClient(zones)
+
+	provider := newAzurePrivateDNSProvider(
+		endpoint.NewDomainFilter([]string{"foo.example.com"}),
+		endpoint.NewDomainFilter([]string{"example.com"}),
+		provider.NewZoneIDFilter([]string{""}),
+		dryRun,
+		"group",
+		&zonesClient,
+		client,
+	)
+
+	createRecords := []*endpoint.Endpoint{
+		endpoint.NewEndpoint("example.com", endpoint.RecordTypeA, "1.2.3.4"),
+		endpoint.NewEndpoint("example.com", endpoint.RecordTypeAAAA, "2001::1:2:3:4"),
+		endpoint.NewEndpoint("example.com", endpoint.RecordTypeTXT, "tag"),
+		endpoint.NewEndpoint("foo.example.com", endpoint.RecordTypeA, "1.2.3.5", "1.2.3.4"),
+		endpoint.NewEndpoint("foo.example.com", endpoint.RecordTypeAAAA, "2001::1:2:3:5", "2001::1:2:3:4"),
+		endpoint.NewEndpoint("foo.example.com", endpoint.RecordTypeTXT, "tag"),
+		endpoint.NewEndpoint("bar.example.com", endpoint.RecordTypeCNAME, "other.com"),
+		endpoint.NewEndpoint("bar.example.com", endpoint.RecordTypeTXT, "tag"),
+		endpoint.NewEndpoint("other.com", endpoint.RecordTypeA, "5.6.7.8"),
+		endpoint.NewEndpoint("other.com", endpoint.RecordTypeTXT, "tag"),
+		endpoint.NewEndpoint("nope.com", endpoint.RecordTypeA, "4.4.4.4"),
+		endpoint.NewEndpoint("nope.com", endpoint.RecordTypeTXT, "tag"),
+	}
+
+	currentRecords := []*endpoint.Endpoint{
+		endpoint.NewEndpoint("old.foo.example.com", endpoint.RecordTypeA, "121.212.121.212"),
+		endpoint.NewEndpoint("oldcname.foo.example.com", endpoint.RecordTypeCNAME, "other.com"),
+		endpoint.NewEndpoint("old.nope.example.com", endpoint.RecordTypeA, "121.212.121.212"),
+	}
+	updatedRecords := []*endpoint.Endpoint{
+		endpoint.NewEndpointWithTTL("new.foo.example.com", endpoint.RecordTypeA, 3600, "111.222.111.222"),
+		endpoint.NewEndpointWithTTL("new.foo.example.com", endpoint.RecordTypeAAAA, 3600, "2001::111:222:111:222"),
+		endpoint.NewEndpointWithTTL("newcname.foo.example.com", endpoint.RecordTypeCNAME, 10, "other.com"),
+		endpoint.NewEndpoint("new.nope.example.com", endpoint.RecordTypeA, "222.111.222.111"),
+		endpoint.NewEndpoint("new.nope.example.com", endpoint.RecordTypeAAAA, "2001::222:111:222:111"),
+	}
+
+	deleteRecords := []*endpoint.Endpoint{
+		endpoint.NewEndpoint("deleted.foo.example.com", endpoint.RecordTypeA, "111.222.111.222"),
+		endpoint.NewEndpoint("deletedaaaa.foo.example.com", endpoint.RecordTypeAAAA, "2001::111:222:111:222"),
+		endpoint.NewEndpoint("deletedcname.foo.example.com", endpoint.RecordTypeCNAME, "other.com"),
+		endpoint.NewEndpoint("deleted.nope.example.com", endpoint.RecordTypeA, "222.111.222.111"),
+	}
+
+	changes := &plan.Changes{
+		Create:    createRecords,
+		UpdateNew: updatedRecords,
+		UpdateOld: currentRecords,
+		Delete:    deleteRecords,
+	}
+
+	if err := provider.ApplyChanges(context.Background(), changes); err != nil {
+		t.Fatal(err)
+	}
+}