Add a cmdline option to add extra volume tags

Add a new cli command option `--extra-volume-tags` which is a map of
string to string (syntax is similar to `--node-labels` for kubelet).  By
default, it's an empty map which maps the the current behavior.

If this option is not empty, when doing dynamic provisioning (i.e., in
`CreateVolume`), we always attach the extra volume tags when calling
`d.cloud.CreateDisk`.

cmd/main.go

@@ -17,23 +17,30 @@ limitations under the License.
 package main
 
 import (
-	"flag"
 	"fmt"
 	"os"
 
 	"github.com/kubernetes-sigs/aws-ebs-csi-driver/pkg/driver"
+	"github.com/spf13/pflag"
+	cliflag "k8s.io/component-base/cli/flag"
 	"k8s.io/klog"
 )
 
 func main() {
 	var (
-		endpoint = flag.String("endpoint", "unix://tmp/csi.sock", "CSI Endpoint")
-		version  = flag.Bool("version", false, "Print the version and exit.")
+		version         bool
+		endpoint        string
+		extraVolumeTags map[string]string
 	)
+
+	pflag.BoolVar(&version, "version", false, "Print the version and exit.")
+	pflag.StringVar(&endpoint, "endpoint", driver.DefaultCSIEndpoint, "CSI Endpoint")
+	pflag.Var(cliflag.NewMapStringString(&extraVolumeTags), "extra-volume-tags", "Extra volume tags to attach to each dynamically provisioned volume. It is a comma separated list of key value pairs like '<key1>=<value1>,<key2>=<value2>'")
+
 	klog.InitFlags(nil)
-	flag.Parse()
+	pflag.Parse()
 
-	if *version {
+	if version {
 		info, err := driver.GetVersionJSON()
 		if err != nil {
 			klog.Fatalln(err)
@@ -42,7 +49,10 @@ func main() {
 		os.Exit(0)
 	}
 
-	drv, err := driver.NewDriver(*endpoint)
+	drv, err := driver.NewDriver(
+		driver.WithEndpoint(endpoint),
+		driver.WithExtraVolumeTags(extraVolumeTags),
+	)
 	if err != nil {
 		klog.Fatalln(err)
 	}

go.mod

@@ -43,7 +43,7 @@ require (
 	github.com/soheilhy/cmux v0.1.4 // indirect
 	github.com/spf13/afero v1.1.2 // indirect
 	github.com/spf13/cobra v0.0.3 // indirect
-	github.com/spf13/pflag v1.0.3 // indirect
+	github.com/spf13/pflag v1.0.3
 	github.com/tmc/grpc-websocket-proxy v0.0.0-20171017195756-830351dc03c6 // indirect
 	github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8 // indirect
 	go.uber.org/atomic v1.3.2 // indirect
@@ -64,6 +64,7 @@ require (
 	k8s.io/api v0.0.0
 	k8s.io/apimachinery v0.0.0
 	k8s.io/client-go v0.0.0
+	k8s.io/component-base v0.0.0
 	k8s.io/klog v0.4.0
 	k8s.io/kubernetes v1.15.2
 )

pkg/cloud/cloud.go

@@ -53,12 +53,20 @@ var (
 )
 
 // AWS provisioning limits.
-// Source: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSVolumeTypes.html
+// Sources:
+//   http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSVolumeTypes.html
+//   https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/Using_Tags.html#tag-restrictions
 const (
 	// MinTotalIOPS represents the minimum Input Output per second.
 	MinTotalIOPS = 100
 	// MaxTotalIOPS represents the maximum Input Output per second.
 	MaxTotalIOPS = 20000
+	// MaxNumTagsPerResource represents the maximum number of tags per AWS resource.
+	MaxNumTagsPerResource = 50
+	// MaxTagKeyLength represents the maximum key length for a tag.
+	MaxTagKeyLength = 128
+	// MaxTagValueLength represents the maximum value length for a tag.
+	MaxTagValueLength = 256
 )
 
 // Defaults
@@ -75,6 +83,10 @@ const (
 	VolumeNameTagKey = "CSIVolumeName"
 	// SnapshotNameTagKey is the key value that refers to the snapshot's name.
 	SnapshotNameTagKey = "CSIVolumeSnapshotName"
+	// KubernetesTagKeyPrefix is the prefix of the key value that is reserved for Kubernetes.
+	KubernetesTagKeyPrefix = "kubernetes.io"
+	// AWSTagKeyPrefix is the prefix of the key value that is reserved for AWS.
+	AWSTagKeyPrefix = "aws:"
 )
 
 var (

pkg/driver/constants.go

@@ -37,3 +37,8 @@ const (
 	// KmsKeyId represents key for KMS encryption key
 	KmsKeyIdKey = "kmskeyid"
 )
+
+// constants for default command line flag values
+const (
+	DefaultCSIEndpoint = "unix://tmp/csi.sock"
+)

pkg/driver/controller.go

@@ -52,19 +52,21 @@ var (
 
 // controllerService represents the controller service of CSI driver
 type controllerService struct {
-	cloud cloud.Cloud
+	cloud         cloud.Cloud
+	driverOptions *DriverOptions
 }
 
 // newControllerService creates a new controller service
 // it panics if failed to create the service
-func newControllerService() controllerService {
+func newControllerService(driverOptions *DriverOptions) controllerService {
 	cloud, err := cloud.NewCloud()
 	if err != nil {
 		panic(err)
 	}
 
 	return controllerService{
-		cloud: cloud,
+		cloud:         cloud,
+		driverOptions: driverOptions,
 	}
 }
 
@@ -140,9 +142,17 @@ func (d *controllerService) CreateVolume(ctx context.Context, req *csi.CreateVol
 
 	// create a new volume
 	zone := pickAvailabilityZone(req.GetAccessibilityRequirements())
+
+	volumeTags := map[string]string{
+		cloud.VolumeNameTagKey: volName,
+	}
+	for k, v := range d.driverOptions.extraVolumeTags {
+		volumeTags[k] = v
+	}
+
 	opts := &cloud.DiskOptions{
 		CapacityBytes:    volSizeBytes,
-		Tags:             map[string]string{cloud.VolumeNameTagKey: volName},
+		Tags:             volumeTags,
 		VolumeType:       volumeType,
 		IOPSPerGB:        iopsPerGB,
 		AvailabilityZone: zone,