Merge pull request #673 from versity/ben/symlinks

feat: add option to allow symlinked directories as buckets

backend/posix/posix.go

@@ -61,6 +61,10 @@ type Posix struct {
 	// used to determine if chowning is needed
 	euid int
 	egid int
+
+	// bucketlinks is a flag to enable symlinks to directories at the top
+	// level gateway directory to be treated as buckets the same as directories
+	bucketlinks bool
 }
 
 var _ backend.Backend = &Posix{}
@@ -87,8 +91,9 @@ const (
 )
 
 type PosixOpts struct {
-	ChownUID bool
-	ChownGID bool
+	ChownUID    bool
+	ChownGID    bool
+	BucketLinks bool
 }
 
 func New(rootdir string, meta meta.MetadataStorer, opts PosixOpts) (*Posix, error) {
@@ -103,13 +108,14 @@ func New(rootdir string, meta meta.MetadataStorer, opts PosixOpts) (*Posix, erro
 	}
 
 	return &Posix{
-		meta:     meta,
-		rootfd:   f,
-		rootdir:  rootdir,
-		euid:     os.Geteuid(),
-		egid:     os.Getegid(),
-		chownuid: opts.ChownUID,
-		chowngid: opts.ChownGID,
+		meta:        meta,
+		rootfd:      f,
+		rootdir:     rootdir,
+		euid:        os.Geteuid(),
+		egid:        os.Getegid(),
+		chownuid:    opts.ChownUID,
+		chowngid:    opts.ChownGID,
+		bucketlinks: opts.BucketLinks,
 	}, nil
 }
 
@@ -130,17 +136,25 @@ func (p *Posix) ListBuckets(_ context.Context, owner string, isAdmin bool) (s3re
 
 	var buckets []s3response.ListAllMyBucketsEntry
 	for _, entry := range entries {
-		if !entry.IsDir() {
-			// buckets must be a directory
-			continue
-		}
-
 		fi, err := entry.Info()
 		if err != nil {
 			// skip entries returning errors
 			continue
 		}
 
+		if p.bucketlinks && entry.Type() == fs.ModeSymlink {
+			fi, err = os.Stat(entry.Name())
+			if err != nil {
+				// skip entries returning errors
+				continue
+			}
+		}
+
+		if !fi.IsDir() {
+			// buckets must be a directory
+			continue
+		}
+
 		// return all the buckets for admin users
 		if isAdmin {
 			buckets = append(buckets, s3response.ListAllMyBucketsEntry{

backend/scoutfs/scoutfs.go

@@ -42,6 +42,7 @@ type ScoutfsOpts struct {
 	ChownUID    bool
 	ChownGID    bool
 	GlacierMode bool
+	BucketLinks bool
 }
 
 type ScoutFS struct {

backend/scoutfs/scoutfs_compat.go

@@ -37,8 +37,9 @@ func New(rootdir string, opts ScoutfsOpts) (*ScoutFS, error) {
 	metastore := meta.XattrMeta{}
 
 	p, err := posix.New(rootdir, metastore, posix.PosixOpts{
-		ChownUID: opts.ChownUID,
-		ChownGID: opts.ChownGID,
+		ChownUID:    opts.ChownUID,
+		ChownGID:    opts.ChownGID,
+		BucketLinks: opts.BucketLinks,
 	})
 	if err != nil {
 		return nil, err

cmd/versitygw/posix.go

@@ -24,6 +24,7 @@ import (
 
 var (
 	chownuid, chowngid bool
+	bucketlinks        bool
 )
 
 func posixCommand() *cli.Command {
@@ -54,6 +55,12 @@ will be translated into the file /mnt/fs/gwroot/mybucket/a/b/c/myobject`,
 				EnvVars:     []string{"VGW_CHOWN_GID"},
 				Destination: &chowngid,
 			},
+			&cli.BoolFlag{
+				Name:        "bucketlinks",
+				Usage:       "allow symlinked directories at bucket level to be treated as buckets",
+				EnvVars:     []string{"VGW_BUCKET_LINKS"},
+				Destination: &bucketlinks,
+			},
 		},
 	}
 }
@@ -70,8 +77,9 @@ func runPosix(ctx *cli.Context) error {
 	}
 
 	be, err := posix.New(gwroot, meta.XattrMeta{}, posix.PosixOpts{
-		ChownUID: chownuid,
-		ChownGID: chowngid,
+		ChownUID:    chownuid,
+		ChownGID:    chowngid,
+		BucketLinks: bucketlinks,
 	})
 	if err != nil {
 		return fmt.Errorf("init posix: %v", err)

cmd/versitygw/scoutfs.go

@@ -63,6 +63,12 @@ move interfaces as well as support for tiered filesystems.`,
 				EnvVars:     []string{"VGW_CHOWN_GID"},
 				Destination: &chowngid,
 			},
+			&cli.BoolFlag{
+				Name:        "bucketlinks",
+				Usage:       "allow symlinked directories at bucket level to be treated as buckets",
+				EnvVars:     []string{"VGW_BUCKET_LINKS"},
+				Destination: &bucketlinks,
+			},
 		},
 	}
 }
@@ -76,6 +82,7 @@ func runScoutfs(ctx *cli.Context) error {
 	opts.GlacierMode = glacier
 	opts.ChownUID = chownuid
 	opts.ChownGID = chowngid
+	opts.BucketLinks = bucketlinks
 
 	be, err := scoutfs.New(ctx.Args().Get(0), opts)
 	if err != nil {

extra/example.conf

@@ -305,6 +305,10 @@ ROOT_SECRET_ACCESS_KEY=
 #VGW_CHOWN_UID=false
 #VGW_CHOWN_GID=false
 
+# The VGW_BUCKET_LINKS option will enable the gateway to treat symbolic links
+# to directories at the top level gateway directory as buckets.
+#VGW_BUCKET_LINKS=false
+
 ###########
 # scoutfs #
 ###########
@@ -336,6 +340,10 @@ ROOT_SECRET_ACCESS_KEY=
 #VGW_CHOWN_UID=false
 #VGW_CHOWN_GID=false
 
+# The VGW_BUCKET_LINKS option will enable the gateway to treat symbolic links
+# to directories at the top level gateway directory as buckets.
+#VGW_BUCKET_LINKS=false
+
 ######
 # s3 #
 ######