add kv isEmpty

pkg/collection/index.go

@@ -194,6 +194,18 @@ func (idx *Index) DeleteIndex(encryptionPassword string) error {
 	return nil
 }
 
+func (idx *Index) IsEmpty(encryptionPassword string) (bool, error) {
+	if idx.memDB == nil || idx.memDB.Entries == nil {
+		manifest, err := idx.loadManifest(idx.name, encryptionPassword)
+		if err != nil {
+			return true, err
+		}
+		idx.memDB = manifest
+	}
+
+	return len(idx.memDB.Entries) == 0, nil
+}
+
 // CountIndex counts the entries in an index.
 func (idx *Index) CountIndex(encryptionPassword string) (uint64, error) {
 	if idx.memDB == nil || idx.memDB.Entries == nil {

pkg/collection/kv.go

@@ -247,6 +247,21 @@ func (kv *KeyValue) KVCount(name, encryptionPassword string) (*TableKeyCount, er
 	}
 }
 
+// IsEmpty checks if the given key value table is empty.
+func (kv *KeyValue) IsEmpty(name, encryptionPassword string) (bool, error) {
+	kv.openKVTMu.Lock()
+	defer kv.openKVTMu.Unlock()
+	if table, ok := kv.openKVTables[name]; ok {
+		return table.index.IsEmpty(table.index.encryptionPassword)
+	} else {
+		idx, err := OpenIndex(kv.podName, defaultCollectionName, name, encryptionPassword, kv.fd, kv.ai, kv.user, kv.client, kv.logger)
+		if err != nil {
+			return true, err
+		}
+		return idx.IsEmpty(idx.encryptionPassword)
+	}
+}
+
 // KVPut inserts a given key and value in to the KV table.
 func (kv *KeyValue) KVPut(name, key string, value []byte) error {
 	if kv.fd.IsReadOnlyFeed() { // skipcq: TCV-001