Google Cloud DNS dnsprovider - replacement for #25389

federation/pkg/dnsprovider/dns.go

@@ -0,0 +1,61 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+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.
+*/
+
+package dnsprovider
+
+import "k8s.io/kubernetes/federation/pkg/dnsprovider/rrstype"
+
+// Interface is an abstract, pluggable interface for DNS providers.
+type Interface interface {
+	// Zones returns the provider's Zones interface, or false if not supported.
+	Zones() (Zones, bool)
+}
+
+type Zones interface {
+	// List returns the managed Zones, or an error if the list operation failed.
+	List() ([]Zone, error)
+}
+
+type Zone interface {
+	// Name returns the name of the zone, e.g. "example.com"
+	Name() string
+	// ResourceRecordsets returns the provider's ResourceRecordSets interface, or false if not supported.
+	ResourceRecordSets() (ResourceRecordSets, bool)
+}
+
+type ResourceRecordSets interface {
+	// List returns the ResourceRecordSets of the Zone, or an error if the list operation failed.
+	List() ([]ResourceRecordSet, error)
+	// Add adds and returns a ResourceRecordSet of the Zone, or an error if the add operation failed.
+	Add(ResourceRecordSet) (ResourceRecordSet, error)
+	// Remove removes a ResourceRecordSet from the Zone, or an error if the remove operation failed.
+	// The supplied ResourceRecordSet must match one of the existing zones (obtained via List()) exactly.
+	Remove(ResourceRecordSet) error
+	// New allocates a new ResourceRecordSet, which can then be passed to Add() or Remove()
+	// Arguments are as per the ResourceRecordSet interface below.
+	New(name string, rrdatas []string, ttl int64, rrstype rrstype.RrsType) ResourceRecordSet
+}
+
+type ResourceRecordSet interface {
+	// Name returns the name of the ResourceRecordSet, e.g. "www.example.com".
+	Name() string
+	// Rrdatas returns the Resource Record Datas of the record set.
+	Rrdatas() []string
+	// Ttl returns the time-to-live of the record set, in seconds.
+	Ttl() int64
+	// Type returns the type of the record set (A, CNAME, SRV, etc)
+	Type() rrstype.RrsType
+}

federation/pkg/dnsprovider/doc.go

@@ -0,0 +1,21 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+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.
+*/
+
+/*
+dnsprovider supplies interfaces for dns service providers (e.g. Google Cloud DNS, AWS route53, etc).
+Implementations exist in the providers sub-package
+*/
+package dnsprovider

federation/pkg/dnsprovider/plugins.go

@@ -0,0 +1,98 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+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.
+*/
+
+package dnsprovider
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"sync"
+
+	"github.com/golang/glog"
+)
+
+// Factory is a function that returns a dnsprovider.Interface.
+// The config parameter provides an io.Reader handler to the factory in
+// order to load specific configurations. If no configuration is provided
+// the parameter is nil.
+type Factory func(config io.Reader) (Interface, error)
+
+// All registered dns providers.
+var providersMutex sync.Mutex
+var providers = make(map[string]Factory)
+
+// RegisterDnsProvider registers a dnsprovider.Factory by name.  This
+// is expected to happen during startup.
+func RegisterDnsProvider(name string, cloud Factory) {
+	providersMutex.Lock()
+	defer providersMutex.Unlock()
+	if _, found := providers[name]; found {
+		glog.Fatalf("DNS provider %q was registered twice", name)
+	}
+	glog.V(1).Infof("Registered DNS provider %q", name)
+	providers[name] = cloud
+}
+
+// GetDnsProvider creates an instance of the named DNS provider, or nil if
+// the name is not known.  The error return is only used if the named provider
+// was known but failed to initialize. The config parameter specifies the
+// io.Reader handler of the configuration file for the DNS provider, or nil
+// for no configuation.
+func GetDnsProvider(name string, config io.Reader) (Interface, error) {
+	providersMutex.Lock()
+	defer providersMutex.Unlock()
+	f, found := providers[name]
+	if !found {
+		return nil, nil
+	}
+	return f(config)
+}
+
+// InitDnsProvider creates an instance of the named DNS provider.
+func InitDnsProvider(name string, configFilePath string) (Interface, error) {
+	var dns Interface
+	var err error
+
+	if name == "" {
+		glog.Info("No DNS provider specified.")
+		return nil, nil
+	}
+
+	if configFilePath != "" {
+		var config *os.File
+		config, err = os.Open(configFilePath)
+		if err != nil {
+			return nil, fmt.Errorf("Couldn't open DNS provider configuration %s: %#v", configFilePath, err)
+		}
+
+		defer config.Close()
+		dns, err = GetDnsProvider(name, config)
+	} else {
+		// Pass explicit nil so plugins can actually check for nil. See
+		// "Why is my nil error value not equal to nil?" in golang.org/doc/faq.
+		dns, err = GetDnsProvider(name, nil)
+	}
+
+	if err != nil {
+		return nil, fmt.Errorf("could not init DNS provider %q: %v", name, err)
+	}
+	if dns == nil {
+		return nil, fmt.Errorf("unknown DNS provider %q", name)
+	}
+
+	return dns, nil
+}

federation/pkg/dnsprovider/providers/google/clouddns/clouddns.go

@@ -0,0 +1,101 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+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.
+*/
+
+// clouddns is the implementation of pkg/dnsprovider interface for Google Cloud DNS
+package clouddns
+
+import (
+	"io"
+
+	"github.com/golang/glog"
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/google"
+	compute "google.golang.org/api/compute/v1"
+	dns "google.golang.org/api/dns/v1"
+	"google.golang.org/cloud/compute/metadata"
+	gcfg "gopkg.in/gcfg.v1"
+
+	"k8s.io/kubernetes/federation/pkg/dnsprovider"
+	"k8s.io/kubernetes/federation/pkg/dnsprovider/providers/google/clouddns/internal"
+	"k8s.io/kubernetes/pkg/cloudprovider/providers/gce"
+)
+
+const (
+	ProviderName = "google-clouddns"
+)
+
+func init() {
+	dnsprovider.RegisterDnsProvider(ProviderName, func(config io.Reader) (dnsprovider.Interface, error) {
+		return newCloudDns(config)
+	})
+}
+
+type Config struct {
+	Global struct {
+		TokenURL  string `gcfg:"token-url"`
+		TokenBody string `gcfg:"token-body"`
+		ProjectID string `gcfg:"project-id"`
+	}
+}
+
+// newCloudDns creates a new instance of a Google Cloud DNS Interface.
+func newCloudDns(config io.Reader) (*Interface, error) {
+	projectID, _ := metadata.ProjectID() // On error we get an empty string, which is fine for now.
+	var tokenSource oauth2.TokenSource
+	// Possibly override defaults with config below
+	if config != nil {
+		var cfg Config
+		if err := gcfg.ReadInto(&cfg, config); err != nil {
+			glog.Errorf("Couldn't read config: %v", err)
+			return nil, err
+		}
+		glog.Infof("Using Google Cloud DNS provider config %+v", cfg)
+		if cfg.Global.ProjectID != "" {
+			projectID = cfg.Global.ProjectID
+		}
+		if cfg.Global.TokenURL != "" {
+			tokenSource = gce.NewAltTokenSource(cfg.Global.TokenURL, cfg.Global.TokenBody)
+		}
+	}
+	return CreateInterface(projectID, tokenSource)
+}
+
+// CreateInterface creates a clouddns.Interface object using the specified parameters.
+// If no tokenSource is specified, uses oauth2.DefaultTokenSource.
+func CreateInterface(projectID string, tokenSource oauth2.TokenSource) (*Interface, error) {
+	if tokenSource == nil {
+		var err error
+		tokenSource, err = google.DefaultTokenSource(
+			oauth2.NoContext,
+			compute.CloudPlatformScope,
+			compute.ComputeScope)
+		glog.Infof("Using DefaultTokenSource %#v", tokenSource)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		glog.Infof("Using existing Token Source %#v", tokenSource)
+	}
+
+	oauthClient := oauth2.NewClient(oauth2.NoContext, tokenSource)
+
+	service, err := dns.New(oauthClient)
+	if err != nil {
+		glog.Errorf("Failed to get Cloud DNS client: %v", err)
+	}
+	glog.Infof("Successfully got DNS service: %v\n", service)
+	return newInterfaceWithStub(projectID, internal.NewService(service)), nil
+}