ethdb: Implement DeleteRange in batch

Author: hadv

ethdb/batch.go

@@ -25,6 +25,10 @@ const IdealBatchSize = 100 * 1024
 type Batch interface {
 	KeyValueWriter
 
+	// DeleteRange deletes all of the keys (and values) in the range [start,end)
+	// (inclusive on start, exclusive on end).
+	DeleteRange(start, end []byte) error
+
 	// ValueSize retrieves the amount of data queued up for writing.
 	ValueSize() int
 
@@ -53,8 +57,9 @@ type Batcher interface {
 type HookedBatch struct {
 	Batch
 
-	OnPut    func(key []byte, value []byte) // Callback if a key is inserted
-	OnDelete func(key []byte)               // Callback if a key is deleted
+	OnPut         func(key []byte, value []byte) // Callback if a key is inserted
+	OnDelete      func(key []byte)               // Callback if a key is deleted
+	OnDeleteRange func(start, end []byte)        // Callback if a range of keys is deleted
 }
 
 // Put inserts the given value into the key-value data store.
@@ -72,3 +77,11 @@ func (b HookedBatch) Delete(key []byte) error {
 	}
 	return b.Batch.Delete(key)
 }
+
+// DeleteRange removes all keys in the range [start, end) from the key-value data store.
+func (b HookedBatch) DeleteRange(start, end []byte) error {
+	if b.OnDeleteRange != nil {
+		b.OnDeleteRange(start, end)
+	}
+	return b.Batch.DeleteRange(start, end)
+}

ethdb/database.go

@@ -38,19 +38,16 @@ type KeyValueWriter interface {
 
 	// Delete removes the key from the key-value data store.
 	Delete(key []byte) error
-}
-
-var ErrTooManyKeys = errors.New("too many keys in deleted range")
 
-// KeyValueRangeDeleter wraps the DeleteRange method of a backing data store.
-type KeyValueRangeDeleter interface {
 	// DeleteRange deletes all of the keys (and values) in the range [start,end)
 	// (inclusive on start, exclusive on end).
 	// Some implementations of DeleteRange may return ErrTooManyKeys after
 	// partially deleting entries in the given range.
-	DeleteRange(start, end []byte) error
+	DeleteRange(start, end []byte) error	
 }
 
+var ErrTooManyKeys = errors.New("too many keys in deleted range")
+
 // KeyValueStater wraps the Stat method of a backing data store.
 type KeyValueStater interface {
 	// Stat returns the statistic data of the database.
@@ -83,7 +80,6 @@ type KeyValueStore interface {
 	KeyValueWriter
 	KeyValueStater
 	KeyValueSyncer
-	KeyValueRangeDeleter
 	Batcher
 	Iteratee
 	Compacter