Merge pull request #3310 from ipfs/kevina/cid2dskey

ds-help: add helper functions to convert from Cid to DsKey and the reverse

blocks/blockstore/blockstore.go

@@ -87,7 +87,7 @@ func (bs *blockstore) Get(k *cid.Cid) (blocks.Block, error) {
 		return nil, ErrNotFound
 	}
 
-	maybeData, err := bs.datastore.Get(dshelp.NewKeyFromBinary(k.KeyString()))
+	maybeData, err := bs.datastore.Get(dshelp.CidToDsKey(k))
 	if err == ds.ErrNotFound {
 		return nil, ErrNotFound
 	}
@@ -112,7 +112,7 @@ func (bs *blockstore) Get(k *cid.Cid) (blocks.Block, error) {
 }
 
 func (bs *blockstore) Put(block blocks.Block) error {
-	k := dshelp.NewKeyFromBinary(block.Cid().KeyString())
+	k := dshelp.CidToDsKey(block.Cid())
 
 	// Has is cheaper than Put, so see if we already have it
 	exists, err := bs.datastore.Has(k)
@@ -128,7 +128,7 @@ func (bs *blockstore) PutMany(blocks []blocks.Block) error {
 		return err
 	}
 	for _, b := range blocks {
-		k := dshelp.NewKeyFromBinary(b.Cid().KeyString())
+		k := dshelp.CidToDsKey(b.Cid())
 		exists, err := bs.datastore.Has(k)
 		if err == nil && exists {
 			continue
@@ -143,11 +143,11 @@ func (bs *blockstore) PutMany(blocks []blocks.Block) error {
 }
 
 func (bs *blockstore) Has(k *cid.Cid) (bool, error) {
-	return bs.datastore.Has(dshelp.NewKeyFromBinary(k.KeyString()))
+	return bs.datastore.Has(dshelp.CidToDsKey(k))
 }
 
 func (s *blockstore) DeleteBlock(k *cid.Cid) error {
-	return s.datastore.Delete(dshelp.NewKeyFromBinary(k.KeyString()))
+	return s.datastore.Delete(dshelp.CidToDsKey(k))
 }
 
 // AllKeysChan runs a query for keys from the blockstore.
@@ -180,17 +180,12 @@ func (bs *blockstore) AllKeysChan(ctx context.Context) (<-chan *cid.Cid, error)
 			}
 
 			// need to convert to key.Key using key.KeyFromDsKey.
-			kb, err := dshelp.BinaryFromDsKey(ds.NewKey(e.Key)) // TODO: calling NewKey isnt free
+			c, err := dshelp.DsKeyToCid(ds.NewKey(e.Key)) // TODO: calling NewKey isnt free
 			if err != nil {
 				log.Warningf("error parsing key from DsKey: ", err)
 				return nil, true
 			}
 
-			c, err := cid.Cast(kb)
-			if err != nil {
-				log.Warning("error parsing cid from decoded DsKey: ", err)
-				return nil, true
-			}
 			log.Debug("blockstore: query got key", c)
 
 			return c, true

blocks/blockstore/blockstore_test.go

@@ -190,7 +190,7 @@ func TestValueTypeMismatch(t *testing.T) {
 	block := blocks.NewBlock([]byte("some data"))
 
 	datastore := ds.NewMapDatastore()
-	k := BlockPrefix.Child(dshelp.NewKeyFromBinary(block.Cid().KeyString()))
+	k := BlockPrefix.Child(dshelp.CidToDsKey(block.Cid()))
 	datastore.Put(k, "data that isn't a block!")
 
 	blockstore := NewBlockstore(ds_sync.MutexWrap(datastore))

thirdparty/ds-help/key.go

@@ -3,6 +3,7 @@ package dshelp
 import (
 	base32 "gx/ipfs/Qmb1DA2A9LS2wR4FFweB4uEDomFsdmnw1VLawLE1yQzudj/base32"
 	ds "gx/ipfs/QmbzuUusHqaLLoNTDEVLcSF6vZDHZDLPC7p4bztRvvkXxU/go-datastore"
+	cid "gx/ipfs/QmXUuRadqDq5BuFWzVU6VuKaSjTcNm1gNCtLvvP1TJCW4z/go-cid"
 )
 
 // TODO: put this code into the go-datastore itself
@@ -13,3 +14,15 @@ func NewKeyFromBinary(s string) ds.Key {
 func BinaryFromDsKey(k ds.Key) ([]byte, error) {
 	return base32.RawStdEncoding.DecodeString(k.String()[1:])
 }
+
+func CidToDsKey(k *cid.Cid) ds.Key {
+	return NewKeyFromBinary(k.KeyString())
+}
+
+func DsKeyToCid(dsKey ds.Key) (*cid.Cid, error) {
+	kb, err := BinaryFromDsKey(dsKey)
+	if err != nil {
+		return nil, err
+	}
+	return cid.Cast(kb)
+}