EFS provider and initialization (#6070)

* EFS initialization

* Remove unused test

* Reorder imports properly

* Change the error package

* Use configuration file from EBS package

* Wrap the unwrapped

pkg/blockstorage/awsebs/awsebs.go

@@ -52,7 +52,7 @@ func (s *ebsStorage) Type() blockstorage.Type {
 
 // NewProvider returns a provider for the EBS storage type in the specified region
 func NewProvider(config map[string]string) (blockstorage.Provider, error) {
-	awsConfig, region, err := getConfig(config)
+	awsConfig, region, err := GetConfig(config)
 	if err != nil {
 		return nil, err
 	}
@@ -63,7 +63,8 @@ func NewProvider(config map[string]string) (blockstorage.Provider, error) {
 	return &ebsStorage{ec2Cli: ec2Cli}, nil
 }
 
-func getConfig(config map[string]string) (*aws.Config, string, error) {
+// GetConfig returns a configuration to establish AWS connection and the connected region name.
+func GetConfig(config map[string]string) (*aws.Config, string, error) {
 	region, ok := config[ConfigRegion]
 	if !ok {
 		return nil, "", errors.New("region required for storage type EBS")

pkg/blockstorage/awsefs/awsefs.go

@@ -2,19 +2,58 @@ package awsefs
 
 import (
 	"context"
-	"errors"
+
+	"github.com/aws/aws-sdk-go/aws"
+	awsarn "github.com/aws/aws-sdk-go/aws/arn"
+	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/aws/aws-sdk-go/service/backup"
+	awsefs "github.com/aws/aws-sdk-go/service/efs"
+	"github.com/aws/aws-sdk-go/service/iam"
+	"github.com/pkg/errors"
 
 	"github.com/kanisterio/kanister/pkg/blockstorage"
+	"github.com/kanisterio/kanister/pkg/blockstorage/awsebs"
 )
 
 type efs struct {
+	*awsefs.EFS
+	*backup.Backup
+	accountID string
+	region    string
 }
 
 var _ blockstorage.Provider = (*efs)(nil)
 
 // NewEFSProvider retuns a blockstorage provider for AWS EFS.
-func NewEFSProvider() blockstorage.Provider {
-	return &efs{}
+func NewEFSProvider(config map[string]string) (blockstorage.Provider, error) {
+	awsConfig, region, err := awsebs.GetConfig(config)
+	if err != nil {
+		return nil, errors.Wrap(err, "Failed to get configuration for EFS")
+	}
+	s, err := session.NewSession(awsConfig)
+	if err != nil {
+		return nil, errors.Wrap(err, "Failed to create session for EFS")
+	}
+	iamCli := iam.New(s, aws.NewConfig().WithRegion(region))
+	user, err := iamCli.GetUser(&iam.GetUserInput{})
+	if err != nil {
+		return nil, errors.Wrap(err, "Failed to get user")
+	}
+	if user.User == nil {
+		return nil, errors.New("Failed to infer user from credentials")
+	}
+	userARN, err := awsarn.Parse(*user.User.Arn)
+	if err != nil {
+		return nil, err
+	}
+	accountID := userARN.AccountID
+	efsCli := awsefs.New(s, aws.NewConfig().WithRegion(region))
+	backupCli := backup.New(s, aws.NewConfig().WithRegion(region))
+	return &efs{
+		EFS:       efsCli,
+		Backup:    backupCli,
+		region:    region,
+		accountID: accountID}, nil
 }
 
 func (e *efs) Type() blockstorage.Type {