Made mtdbconverter pass golint by adding the missing comments.

cmd/mtdbconverter/leveldb.go

@@ -13,6 +13,7 @@ import (
 )
 
 type (
+	// LevelDBBlockProducer is a helper to fetch blocks from a LevelDB.
 	LevelDBBlockProducer struct {
 		db       *leveldb.DB
 		opts     *leveldb.Options
@@ -22,6 +23,7 @@ type (
 		decoder  common.KeyDecoder
 	}
 
+	// LevelDBBlockConsumer is a helper to store blocks in a LevelDB.
 	LevelDBBlockConsumer struct {
 		db      *leveldb.DB
 		opts    *leveldb.Options
@@ -31,6 +33,7 @@ type (
 	}
 )
 
+// NewLevelDBBlockProducer returns a new helper to fetch blocks from a LevelDB.
 func NewLevelDBBlockProducer(path string,
 	splitter common.KeySplitter,
 	decoder common.KeyDecoder) (ldbp *LevelDBBlockProducer, err error) {
@@ -65,6 +68,7 @@ func NewLevelDBBlockProducer(path string,
 	return
 }
 
+// Close closes a helper to fetch blocks from a LevelDB.
 func (ldbp *LevelDBBlockProducer) Close() error {
 	if ldbp.iterator != nil {
 		ldbp.iterator.Close()
@@ -75,6 +79,7 @@ func (ldbp *LevelDBBlockProducer) Close() error {
 	return nil
 }
 
+// Next fetches the next block from a LevelDB.
 func (ldbp *LevelDBBlockProducer) Next(block *common.Block) (err error) {
 	if ldbp.iterator == nil {
 		err = common.ErrNoMoreBlocks
@@ -98,6 +103,7 @@ func (ldbp *LevelDBBlockProducer) Next(block *common.Block) (err error) {
 	return
 }
 
+// NewLevelDBBlockConsumer returns a new helper to store blocks in a LevelDB.
 func NewLevelDBBlockConsumer(
 	path string,
 	joiner common.KeyJoiner,
@@ -120,6 +126,7 @@ func NewLevelDBBlockConsumer(
 	return
 }
 
+// Close closes a helper to store blocks in a LevelDB.
 func (ldbc *LevelDBBlockConsumer) Close() error {
 	ldbc.wo.Close()
 	ldbc.db.Close()
@@ -127,6 +134,7 @@ func (ldbc *LevelDBBlockConsumer) Close() error {
 	return nil
 }
 
+// Consume stores a block in LevelDB.
 func (ldbc *LevelDBBlockConsumer) Consume(block *common.Block) (err error) {
 	var encodedKey []byte
 	if encodedKey, err = ldbc.encoder(ldbc.joiner(block.Coord)); err != nil {

cmd/mtdbconverter/sqlite.go

@@ -21,17 +21,20 @@ const (
 	selectSQL = "SELECT pos, data FROM blocks"
 )
 
+// ErrDatabaseNotExists indicates that the database does not exist.
 var ErrDatabaseNotExists = errors.New("Database does not exists.")
 
-const blocksPerTx = 128
+const blocksPerTx = 128 // Number of blocks copied in a transaction.
 
 type (
+	// SQLiteBlockProducer helps getting blocks from a SQLite database.
 	SQLiteBlockProducer struct {
 		db       *sql.DB
 		rows     *sql.Rows
 		splitter common.KeySplitter
 	}
 
+	// SQLiteBlockConsumer helps storing blocks into a SQLite database.
 	SQLiteBlockConsumer struct {
 		db         *sql.DB
 		insertStmt *sql.Stmt
@@ -46,6 +49,7 @@ func fileExists(path string) bool {
 	return !os.IsNotExist(err)
 }
 
+// NewSQLiteBlockConsumer returns a storage helper for SQLite databases.
 func NewSQLiteBlockConsumer(
 	path string,
 	joiner common.KeyJoiner) (sbc *SQLiteBlockConsumer, err error) {
@@ -91,6 +95,7 @@ func NewSQLiteBlockConsumer(
 	return
 }
 
+// Close closes a SQLite storage helper.
 func (sbc *SQLiteBlockConsumer) Close() error {
 	sbc.tx.Commit()
 	sbc.insertStmt.Close()
@@ -112,6 +117,7 @@ func (sbc *SQLiteBlockConsumer) getTx() (tx *sql.Tx, err error) {
 	return
 }
 
+// Consume stores a block in an SQLite database.
 func (sbc *SQLiteBlockConsumer) Consume(block *common.Block) (err error) {
 	var tx *sql.Tx
 	if tx, err = sbc.getTx(); err != nil {
@@ -121,6 +127,8 @@ func (sbc *SQLiteBlockConsumer) Consume(block *common.Block) (err error) {
 	return
 }
 
+// NewSQLiteBlockProducer returns a new producer to fetch blocks from a
+// SQLite database.
 func NewSQLiteBlockProducer(
 	path string,
 	splitter common.KeySplitter) (sbp *SQLiteBlockProducer, err error) {
@@ -149,6 +157,7 @@ func NewSQLiteBlockProducer(
 	return
 }
 
+// Next fetches the next block from a SQLite database.
 func (sbp *SQLiteBlockProducer) Next(block *common.Block) (err error) {
 	if sbp.rows == nil {
 		err = common.ErrNoMoreBlocks
@@ -167,6 +176,7 @@ func (sbp *SQLiteBlockProducer) Next(block *common.Block) (err error) {
 	return
 }
 
+// Close closes a block producer from a SQLite database.
 func (sbp *SQLiteBlockProducer) Close() error {
 	if sbp.rows != nil {
 		sbp.rows.Close()