[#472] blobstor: move fsTree to a separate package

Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>

pkg/local_object_storage/blobstor/blobstor.go

@@ -6,6 +6,7 @@ import (
 	"path"
 
 	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobovnicza"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
 	"github.com/nspcc-dev/neofs-node/pkg/util/logger"
 	"go.uber.org/zap"
 )
@@ -17,11 +18,13 @@ type BlobStor struct {
 	blobovniczas *blobovniczas
 }
 
+type Info = fstree.Info
+
 // Option represents BlobStor's constructor option.
 type Option func(*cfg)
 
 type cfg struct {
-	fsTree fsTree
+	fsTree fstree.FSTree
 
 	compressor func([]byte) []byte
 
@@ -54,9 +57,9 @@ const blobovniczaDir = "blobovnicza"
 
 func defaultCfg() *cfg {
 	return &cfg{
-		fsTree: fsTree{
+		fsTree: fstree.FSTree{
-			depth:      defaultShallowDepth,
+			Depth:      defaultShallowDepth,
-			dirNameLen: hex.EncodedLen(dirNameLen),
+			DirNameLen: hex.EncodedLen(fstree.DirNameLen),
 			Info: Info{
 				Permissions: defaultPerm,
 				RootPath:    "./",
@@ -92,11 +95,11 @@ func New(opts ...Option) *BlobStor {
 // Depth is reduced to maximum value in case of overflow.
 func WithShallowDepth(depth int) Option {
 	return func(c *cfg) {
-		if depth > maxDepth {
+		if depth > fstree.MaxDepth {
-			depth = maxDepth
+			depth = fstree.MaxDepth
 		}
 
-		c.fsTree.depth = depth
+		c.fsTree.Depth = depth
 	}
 }
 

pkg/local_object_storage/blobstor/delete_big.go

@@ -1,10 +1,8 @@
 package blobstor
 
 import (
-	"os"
-
-	objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
 	"github.com/nspcc-dev/neofs-node/pkg/core/object"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
 	"github.com/pkg/errors"
 )
 
@@ -23,19 +21,10 @@ type DeleteBigRes struct{}
 //
 // Returns ErrNotFound if there is no object to delete.
 func (b *BlobStor) DeleteBig(prm *DeleteBigPrm) (*DeleteBigRes, error) {
-	err := b.fsTree.delete(prm.addr)
+	err := b.fsTree.Delete(prm.addr)
-	if errors.Is(err, errFileNotFound) {
+	if errors.Is(err, fstree.ErrFileNotFound) {
 		err = object.ErrNotFound
 	}
 
 	return nil, err
 }
-
-func (t *fsTree) delete(addr *objectSDK.Address) error {
-	p, err := t.exists(addr)
-	if err != nil {
-		return err
-	}
-
-	return os.Remove(p)
-}

pkg/local_object_storage/blobstor/exists.go

@@ -1,10 +1,8 @@
 package blobstor
 
 import (
-	"os"
-
 	"github.com/nspcc-dev/neofs-api-go/pkg/object"
-	objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
 	"github.com/pkg/errors"
 )
 
@@ -48,8 +46,8 @@ func (b *BlobStor) Exists(prm *ExistsPrm) (*ExistsRes, error) {
 
 // checks if object is presented in shallow dir.
 func (b *BlobStor) existsBig(addr *object.Address) (bool, error) {
-	_, err := b.fsTree.exists(addr)
+	_, err := b.fsTree.Exists(addr)
-	if errors.Is(err, errFileNotFound) {
+	if errors.Is(err, fstree.ErrFileNotFound) {
 		return false, nil
 	}
 
@@ -61,14 +59,3 @@ func (b *BlobStor) existsSmall(addr *object.Address) (bool, error) {
 	// TODO: implement
 	return false, nil
 }
-
-func (t *fsTree) exists(addr *objectSDK.Address) (string, error) {
-	p := t.treePath(addr)
-
-	_, err := os.Stat(p)
-	if os.IsNotExist(err) {
-		err = errFileNotFound
-	}
-
-	return p, err
-}

pkg/local_object_storage/blobstor/fstree.go

@@ -1,46 +0,0 @@
-package blobstor
-
-import (
-	"crypto/sha256"
-	"encoding/hex"
-	"errors"
-	"path"
-
-	objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
-)
-
-type fsTree struct {
-	depth int
-
-	dirNameLen int
-
-	Info
-}
-
-const dirNameLen = 1 // in bytes
-
-var maxDepth = (sha256.Size - 1) / dirNameLen
-
-var errFileNotFound = errors.New("file not found")
-
-func stringifyAddress(addr *objectSDK.Address) string {
-	h := sha256.Sum256([]byte(addr.String()))
-
-	return hex.EncodeToString(h[:])
-}
-
-func (t *fsTree) treePath(addr *objectSDK.Address) string {
-	sAddr := stringifyAddress(addr)
-
-	dirs := make([]string, 0, t.depth+1+1) // 1 for root, 1 for file
-	dirs = append(dirs, t.RootPath)
-
-	for i := 0; i < t.depth; i++ {
-		dirs = append(dirs, sAddr[:t.dirNameLen])
-		sAddr = sAddr[t.dirNameLen:]
-	}
-
-	dirs = append(dirs, sAddr)
-
-	return path.Join(dirs...)
-}

pkg/local_object_storage/blobstor/fstree/fstree.go

@@ -0,0 +1,106 @@
+package fstree
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"errors"
+	"io/ioutil"
+	"os"
+	"path"
+
+	objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
+)
+
+// FSTree represents object storage as filesystem tree.
+type FSTree struct {
+	Info
+
+	Depth      int
+	DirNameLen int
+}
+
+// Info groups the information about file storage.
+type Info struct {
+	// Permission bits of the root directory.
+	Permissions os.FileMode
+
+	// Full path to the root directory.
+	RootPath string
+}
+
+const (
+	// DirNameLen is how many bytes is used to group keys into directories.
+	DirNameLen = 1 // in bytes
+	// MaxDepth is maximum depth of nested directories.
+	MaxDepth = (sha256.Size - 1) / DirNameLen
+)
+
+// ErrFileNotFound is returned when file is missing.
+var ErrFileNotFound = errors.New("file not found")
+
+func stringifyAddress(addr *objectSDK.Address) string {
+	h := sha256.Sum256([]byte(addr.String()))
+
+	return hex.EncodeToString(h[:])
+}
+
+func (t *FSTree) treePath(addr *objectSDK.Address) string {
+	sAddr := stringifyAddress(addr)
+
+	dirs := make([]string, 0, t.Depth+1+1) // 1 for root, 1 for file
+	dirs = append(dirs, t.RootPath)
+
+	for i := 0; i < t.Depth; i++ {
+		dirs = append(dirs, sAddr[:t.DirNameLen])
+		sAddr = sAddr[t.DirNameLen:]
+	}
+
+	dirs = append(dirs, sAddr)
+
+	return path.Join(dirs...)
+}
+
+// Delete removes object with the specified address from storage.
+func (t *FSTree) Delete(addr *objectSDK.Address) error {
+	p, err := t.Exists(addr)
+	if err != nil {
+		return err
+	}
+
+	return os.Remove(p)
+}
+
+// Exists returns path to file with object contents if it exists in storage
+// and an error otherwise.
+func (t *FSTree) Exists(addr *objectSDK.Address) (string, error) {
+	p := t.treePath(addr)
+
+	_, err := os.Stat(p)
+	if os.IsNotExist(err) {
+		err = ErrFileNotFound
+	}
+
+	return p, err
+}
+
+// Put puts object in storage.
+func (t *FSTree) Put(addr *objectSDK.Address, data []byte) error {
+	p := t.treePath(addr)
+
+	if err := os.MkdirAll(path.Dir(p), t.Permissions); err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(p, data, t.Permissions)
+}
+
+// Get returns object from storage by address.
+func (t *FSTree) Get(addr *objectSDK.Address) ([]byte, error) {
+	p := t.treePath(addr)
+
+	if _, err := os.Stat(p); os.IsNotExist(err) {
+		return nil, ErrFileNotFound
+	}
+
+	return ioutil.ReadFile(p)
+}

pkg/local_object_storage/blobstor/get_big.go

@@ -1,11 +1,8 @@
 package blobstor
 
 import (
-	"io/ioutil"
-	"os"
-
-	objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
 	"github.com/nspcc-dev/neofs-node/pkg/core/object"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
 	"github.com/pkg/errors"
 )
 
@@ -28,9 +25,9 @@ type GetBigRes struct {
 // presented in shallow dir.
 func (b *BlobStor) GetBig(prm *GetBigPrm) (*GetBigRes, error) {
 	// get compressed object data
-	data, err := b.fsTree.get(prm.addr)
+	data, err := b.fsTree.Get(prm.addr)
 	if err != nil {
-		if errors.Is(err, errFileNotFound) {
+		if errors.Is(err, fstree.ErrFileNotFound) {
 			return nil, object.ErrNotFound
 		}
 
@@ -54,13 +51,3 @@ func (b *BlobStor) GetBig(prm *GetBigPrm) (*GetBigRes, error) {
 		},
 	}, nil
 }
-
-func (t *fsTree) get(addr *objectSDK.Address) ([]byte, error) {
-	p := t.treePath(addr)
-
-	if _, err := os.Stat(p); os.IsNotExist(err) {
-		return nil, errFileNotFound
-	}
-
-	return ioutil.ReadFile(p)
-}

pkg/local_object_storage/blobstor/get_range_big.go

@@ -24,7 +24,7 @@ type GetRangeBigRes struct {
 // Returns ErrRangeOutOfBounds if requested object range is out of bounds.
 func (b *BlobStor) GetRangeBig(prm *GetRangeBigPrm) (*GetRangeBigRes, error) {
 	// get compressed object data
-	data, err := b.fsTree.get(prm.addr)
+	data, err := b.fsTree.Get(prm.addr)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not read object from fs tree")
 	}

pkg/local_object_storage/blobstor/info.go

@@ -1,19 +1,8 @@
 package blobstor
 
-import (
+import "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
-	"os"
-)
-
-// Info groups the information about BlobStor.
-type Info struct {
-	// Permission bits of the root directory.
-	Permissions os.FileMode
-
-	// Full path to the root directory.
-	RootPath string
-}
 
 // DumpInfo returns information about the BlobStor.
-func (b *BlobStor) DumpInfo() Info {
+func (b *BlobStor) DumpInfo() fstree.Info {
 	return b.fsTree.Info
 }

pkg/local_object_storage/blobstor/put.go

@@ -1,11 +1,6 @@
 package blobstor
 
 import (
-	"io/ioutil"
-	"os"
-	"path"
-
-	objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
 	"github.com/pkg/errors"
 )
 
@@ -41,7 +36,7 @@ func (b *BlobStor) Put(prm *PutPrm) (*PutRes, error) {
 
 	if big {
 		// save object in shallow dir
-		return new(PutRes), b.fsTree.put(prm.obj.Address(), data)
+		return new(PutRes), b.fsTree.Put(prm.obj.Address(), data)
 	}
 
 	// save object in blobovnicza
@@ -57,16 +52,6 @@ func (b *BlobStor) Put(prm *PutPrm) (*PutRes, error) {
 	}, nil
 }
 
-func (t *fsTree) put(addr *objectSDK.Address, data []byte) error {
-	p := t.treePath(addr)
-
-	if err := os.MkdirAll(path.Dir(p), t.Permissions); err != nil {
-		return err
-	}
-
-	return ioutil.WriteFile(p, data, t.Permissions)
-}
-
 // checks if object is "big".
 func (b *BlobStor) isBig(data []byte) bool {
 	return uint64(len(data)) > b.smallSizeLimit