dedupe: record relative path for cache entries

In a production use case we found that the actual rootdir can be moved.
Currently, cache entries for dedupe record the full blob path which
doesn't work in the move use case.

Only for dedupe cache entries, record relative blob paths.

pkg/storage/cache.go

@@ -2,6 +2,7 @@ package storage
 
 import (
 	"path"
+	"path/filepath"
 	"strings"
 
 	"github.com/anuvu/zot/errors"
@@ -14,8 +15,9 @@ const (
 )
 
 type Cache struct {
-	db  *bbolt.DB
+	rootDir string
-	log zlog.Logger
+	db      *bbolt.DB
+	log     zlog.Logger
 }
 
 // Blob is a blob record
@@ -45,10 +47,16 @@ func NewCache(rootDir string, name string, log zlog.Logger) *Cache {
 		return nil
 	}
 
-	return &Cache{db: db, log: log}
+	return &Cache{rootDir: rootDir, db: db, log: log}
 }
 
 func (c *Cache) PutBlob(digest string, path string) error {
+	// use only relative (to rootDir) paths on blobs
+	relp, err := filepath.Rel(c.rootDir, path)
+	if err != nil {
+		c.log.Error().Err(err).Str("path", path).Msg("unable to get relative path")
+	}
+
 	if err := c.db.Update(func(tx *bbolt.Tx) error {
 		root := tx.Bucket([]byte(BlobsCache))
 		if root == nil {
@@ -63,8 +71,8 @@ func (c *Cache) PutBlob(digest string, path string) error {
 			c.log.Error().Err(err).Str("bucket", digest).Msg("unable to create a bucket")
 			return err
 		}
-		if err := b.Put([]byte(path), nil); err != nil {
+		if err := b.Put([]byte(relp), nil); err != nil {
-			c.log.Error().Err(err).Str("bucket", digest).Str("value", path).Msg("unable to put record")
+			c.log.Error().Err(err).Str("bucket", digest).Str("value", relp).Msg("unable to put record")
 			return err
 		}
 		return nil
@@ -135,6 +143,12 @@ func (c *Cache) HasBlob(digest string, blob string) bool {
 }
 
 func (c *Cache) DeleteBlob(digest string, path string) error {
+	// use only relative (to rootDir) paths on blobs
+	relp, err := filepath.Rel(c.rootDir, path)
+	if err != nil {
+		c.log.Error().Err(err).Str("path", path).Msg("unable to get relative path")
+	}
+
 	if err := c.db.Update(func(tx *bbolt.Tx) error {
 		root := tx.Bucket([]byte(BlobsCache))
 		if root == nil {
@@ -149,8 +163,8 @@ func (c *Cache) DeleteBlob(digest string, path string) error {
 			return errors.ErrCacheMiss
 		}
 
-		if err := b.Delete([]byte(path)); err != nil {
+		if err := b.Delete([]byte(relp)); err != nil {
-			c.log.Error().Err(err).Str("digest", digest).Str("path", path).Msg("unable to delete")
+			c.log.Error().Err(err).Str("digest", digest).Str("path", relp).Msg("unable to delete")
 			return err
 		}
 
@@ -158,9 +172,9 @@ func (c *Cache) DeleteBlob(digest string, path string) error {
 		k, _ := cur.First()
 
 		if k == nil {
-			c.log.Debug().Str("digest", digest).Str("path", path).Msg("deleting empty bucket")
+			c.log.Debug().Str("digest", digest).Str("path", relp).Msg("deleting empty bucket")
 			if err := root.DeleteBucket([]byte(digest)); err != nil {
-				c.log.Error().Err(err).Str("digest", digest).Str("path", path).Msg("unable to delete")
+				c.log.Error().Err(err).Str("digest", digest).Str("path", relp).Msg("unable to delete")
 				return err
 			}
 		}

pkg/storage/cache_test.go

@@ -3,6 +3,7 @@ package storage_test
 import (
 	"io/ioutil"
 	"os"
+	"path"
 	"testing"
 
 	"github.com/anuvu/zot/errors"
@@ -33,7 +34,7 @@ func TestCache(t *testing.T) {
 		b := c.HasBlob("key", "value")
 		So(b, ShouldBeFalse)
 
-		err = c.PutBlob("key", "value")
+		err = c.PutBlob("key", path.Join(dir, "value"))
 		So(err, ShouldBeNil)
 
 		b = c.HasBlob("key", "value")

pkg/storage/storage.go

@@ -849,6 +849,8 @@ retry:
 		}
 		is.log.Debug().Str("src", src).Str("dst", dst).Msg("dedupe: rename")
 	} else {
+		dstRecord = path.Join(is.rootDir, dstRecord)
+
 		dstRecordFi, err := os.Stat(dstRecord)
 		if err != nil {
 			is.log.Error().Err(err).Str("blobPath", dstRecord).Msg("dedupe: unable to stat")