Add volume ID append dimension for disk metrics (#1156)

plugins/processors/ec2tagger/config.go

@@ -16,6 +16,11 @@ var SupportedAppendDimensions = map[string]string{
 	"InstanceType":         "${aws:InstanceType}",
 }
 
+const (
+	AttributeVolumeId            = "VolumeId"
+	ValueAppendDimensionVolumeId = "${aws:VolumeId}"
+)
+
 type Config struct {
 	RefreshIntervalSeconds time.Duration `mapstructure:"refresh_interval_seconds"`
 	EC2MetadataTags        []string      `mapstructure:"ec2_metadata_tags"`

plugins/processors/ec2tagger/constants.go

@@ -65,7 +65,6 @@ const (
 	mdKeyInstanceId      = "InstanceId"
 	mdKeyImageId         = "ImageId"
 	mdKeyInstanceType    = "InstanceType"
-	ebsVolumeId          = "EBSVolumeId"
 )
 
 var (

plugins/processors/ec2tagger/ec2tagger.go

@@ -19,6 +19,7 @@ import (
 	"go.uber.org/zap"
 
 	configaws "github.com/aws/amazon-cloudwatch-agent/cfg/aws"
+	"github.com/aws/amazon-cloudwatch-agent/plugins/processors/ec2tagger/internal/volume"
 	translatorCtx "github.com/aws/amazon-cloudwatch-agent/translator/context"
 )
 
@@ -52,14 +53,13 @@ type Tagger struct {
 	ec2MetadataRespond ec2MetadataRespondType
 	tagFilters         []*ec2.Filter
 	ec2API             ec2iface.EC2API
-	ebsVolume          *EbsVolume
+	volumeSerialCache  volume.Cache
 
 	sync.RWMutex //to protect ec2TagCache
 }
 
 // newTagger returns a new EC2 Tagger processor.
 func newTagger(config *Config, logger *zap.Logger) *Tagger {
-
 	_, cancel := context.WithCancel(context.Background())
 	mdCredentialConfig := &configaws.CredentialConfig{}
 
@@ -77,7 +77,6 @@ func newTagger(config *Config, logger *zap.Logger) *Tagger {
 				})
 		},
 	}
-
 	return p
 }
 
@@ -146,11 +145,11 @@ func (t *Tagger) updateOtelAttributes(attributes []pcommon.Map) {
 		if t.ec2MetadataLookup.instanceType {
 			attr.PutStr(mdKeyInstanceType, t.ec2MetadataRespond.instanceType)
 		}
-		if t.ebsVolume != nil {
+		if t.volumeSerialCache != nil {
 			if devName, found := attr.Get(t.DiskDeviceTagKey); found {
-				ebsVolId := t.ebsVolume.getEbsVolumeId(devName.Str())
-				if ebsVolId != "" {
-					attr.PutStr(ebsVolumeId, ebsVolId)
+				serial := t.volumeSerialCache.Serial(devName.Str())
+				if serial != "" {
+					attr.PutStr(AttributeVolumeId, serial)
 				}
 			}
 		}
@@ -270,7 +269,7 @@ func (t *Tagger) ebsVolumesRetrieved() bool {
 		if key == "*" {
 			continue
 		}
-		if volId := t.ebsVolume.getEbsVolumeId(key); volId == "" {
+		if volId := t.volumeSerialCache.Serial(key); volId == "" {
 			allVolumesRetrieved = false
 			break
 		}
@@ -280,7 +279,7 @@ func (t *Tagger) ebsVolumesRetrieved() bool {
 
 // Start acts as input validation and serves the purpose of updating ec2 tags and ebs volumes if necessary.
 // It will be called when OTel is enabling each processor
-func (t *Tagger) Start(ctx context.Context, host component.Host) error {
+func (t *Tagger) Start(ctx context.Context, _ component.Host) error {
 	t.shutdownC = make(chan bool)
 	t.ec2TagCache = map[string]string{}
 
@@ -373,34 +372,15 @@ func (t *Tagger) refreshLoopToUpdateTagsAndVolumes() {
 
 // updateVolumes calls EC2 describe volume
 func (t *Tagger) updateVolumes() error {
-	if t.ebsVolume == nil {
-		t.ebsVolume = NewEbsVolume()
+	if t.volumeSerialCache == nil {
+		t.volumeSerialCache = volume.NewCache(volume.NewProvider(t.ec2API, t.ec2MetadataRespond.instanceId))
 	}
 
-	input := &ec2.DescribeVolumesInput{
-		Filters: []*ec2.Filter{
-			{
-				Name:   aws.String("attachment.instance-id"),
-				Values: aws.StringSlice([]string{t.ec2MetadataRespond.instanceId}),
-			},
-		},
+	if err := t.volumeSerialCache.Refresh(); err != nil {
+		return err
 	}
 
-	for {
-		result, err := t.ec2API.DescribeVolumes(input)
-		if err != nil {
-			return err
-		}
-		for _, volume := range result.Volumes {
-			for _, attachment := range volume.Attachments {
-				t.ebsVolume.addEbsVolumeMapping(volume.AvailabilityZone, attachment)
-			}
-		}
-		if result.NextToken == nil {
-			break
-		}
-		input.SetNextToken(*result.NextToken)
-	}
+	t.logger.Debug("Volume Serial Cache", zap.Strings("devices", t.volumeSerialCache.Devices()))
 	return nil
 }