Add fs prefix (directory)

This ensures the fs root is clean and does not mess with
the metadata. Also in the future this will allow for multiple
filesystems to be created in one bucket.

pkg/s3/controllerserver.go

@@ -61,7 +61,7 @@ func (cs *controllerServer) CreateVolume(ctx context.Context, req *csi.CreateVol
 		var b *bucket
 		b, err = cs.s3.client.getBucket(volumeID)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("failed to get bucket: %v", err)
 		}
 		// Check if volume capacity requested is bigger than the already existing capacity
 		if capacityBytes > b.CapacityBytes {
@@ -69,16 +69,19 @@ func (cs *controllerServer) CreateVolume(ctx context.Context, req *csi.CreateVol
 		}
 	} else {
 		if err = cs.s3.client.createBucket(volumeID); err != nil {
-			glog.V(3).Infof("failed to create volume: %v", err)
+			return nil, fmt.Errorf("failed to create volume: %v", err)
-			return nil, err
+		}
+		if err = cs.s3.client.createPrefix(volumeID, fsPrefix); err != nil {
+			return nil, fmt.Errorf("failed to create prefix: %v", err)
 		}
 	}
 	b := &bucket{
 		Name:          volumeID,
 		CapacityBytes: capacityBytes,
+		FSPath:        fsPrefix,
 	}
 	if err := cs.s3.client.setBucket(b); err != nil {
-		return nil, err
+		return nil, fmt.Errorf("Error setting bucket metadata: %v", err)
 	}
 
 	glog.V(4).Infof("create volume %s", volumeID)

pkg/s3/mounter_goofys.go

@@ -60,8 +60,9 @@ func (goofys *goofysMounter) Mount(source string, target string) error {
 
 	os.Setenv("AWS_ACCESS_KEY_ID", goofys.accessKeyID)
 	os.Setenv("AWS_SECRET_ACCESS_KEY", goofys.secretAccessKey)
+	fullPath := fmt.Sprintf("%s:%s", goofys.bucket.Name, goofys.bucket.FSPath)
 
-	_, _, err := goofysApi.Mount(context.Background(), goofys.bucket.Name, goofysCfg)
+	_, _, err := goofysApi.Mount(context.Background(), fullPath, goofysCfg)
 
 	if err != nil {
 		return fmt.Errorf("Error mounting via goofys: %s", err)

pkg/s3/mounter_s3backer.go

@@ -2,6 +2,7 @@ package s3
 
 import (
 	"fmt"
+	"net/url"
 	"os"
 	"os/exec"
 	"path"
@@ -29,6 +30,11 @@ const (
 )
 
 func newS3backerMounter(bucket *bucket, cfg *Config) (Mounter, error) {
+	url, err := url.Parse(cfg.Endpoint)
+	if err != nil {
+		return nil, err
+	}
+	url.Path = path.Join(url.Path, bucket.Name, bucket.FSPath)
 	// s3backer cannot work with 0 size volumes
 	if bucket.CapacityBytes == 0 {
 		bucket.CapacityBytes = s3backerDefaultSize
@@ -88,8 +94,9 @@ func (s3backer *s3backerMounter) mountInit(path string) error {
 	args := []string{
 		// baseURL must end with /
 		fmt.Sprintf("--baseURL=%s/", s3backer.url),
-		fmt.Sprintf("--blockSize=%v", s3backerBlockSize),
+		fmt.Sprintf("--blockSize=%s", s3backerBlockSize),
 		fmt.Sprintf("--size=%v", s3backer.bucket.CapacityBytes),
+		fmt.Sprintf("--prefix=%s/", s3backer.bucket.FSPath),
 		"--listBlocks",
 		s3backer.bucket.Name,
 		path,

pkg/s3/mounter_s3fs.go

@@ -39,7 +39,7 @@ func (s3fs *s3fsMounter) Mount(source string, target string) error {
 		return err
 	}
 	args := []string{
-		fmt.Sprintf("%s", s3fs.bucket.Name),
+		fmt.Sprintf("%s:/%s", s3fs.bucket.Name, s3fs.bucket.FSPath),
 		fmt.Sprintf("%s", target),
 		"-o", "sigv2",
 		"-o", "use_path_request_style",

pkg/s3/mounter_s3ql.go

@@ -49,7 +49,9 @@ func newS3qlMounter(b *bucket, cfg *Config) (Mounter, error) {
 		ssl:        ssl,
 	}
 
-	url.Path = path.Join(url.Path, b.Name)
+	// s3ql requires a trailing slash or it will just
+	// prepend the fspath to the s3ql files
+	url.Path = path.Join(url.Path, b.Name, b.FSPath) + "/"
 	s3ql.bucketURL = url.String()
 
 	if !ssl {

pkg/s3/s3-client.go

@@ -13,6 +13,7 @@ import (
 
 const (
 	metadataName = ".metadata.json"
+	fsPrefix     = "csi-fs"
 )
 
 type s3Client struct {
@@ -22,6 +23,7 @@ type s3Client struct {
 
 type bucket struct {
 	Name          string
+	FSPath        string
 	CapacityBytes int64
 }
 
@@ -54,6 +56,14 @@ func (client *s3Client) createBucket(bucketName string) error {
 	return client.minio.MakeBucket(bucketName, client.cfg.Region)
 }
 
+func (client *s3Client) createPrefix(bucketName string, prefix string) error {
+	_, err := client.minio.PutObject(bucketName, prefix+"/", bytes.NewReader([]byte("")), 0, minio.PutObjectOptions{})
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func (client *s3Client) removeBucket(bucketName string) error {
 	if err := client.emptyBucket(bucketName); err != nil {
 		return err