New NewGoLevelDBWithOpts() to pass opts down to goleveldb (#2293)

Closes: #2292

CHANGELOG_PENDING.md

@@ -23,6 +23,7 @@ BREAKING CHANGES:
 
 FEATURES:
 - [types] allow genesis file to have 0 validators ([#2015](https://github.com/tendermint/tendermint/issues/2015))
+- [libs] allow passing options through when creating instances of leveldb dbs ([#2292](https://github.com/tendermint/tendermint/issues/2292))
 
 IMPROVEMENTS:
 - [docs] Lint documentation with `write-good` and `stop-words`.

libs/db/go_level_db.go

@@ -28,8 +28,12 @@ type GoLevelDB struct {
 }
 
 func NewGoLevelDB(name string, dir string) (*GoLevelDB, error) {
+	return NewGoLevelDBWithOpts(name, dir, nil)
+}
+
+func NewGoLevelDBWithOpts(name string, dir string, o *opt.Options) (*GoLevelDB, error) {
 	dbPath := filepath.Join(dir, name+".db")
-	db, err := leveldb.OpenFile(dbPath, nil)
+	db, err := leveldb.OpenFile(dbPath, o)
 	if err != nil {
 		return nil, err
 	}

libs/db/go_level_db_test.go

@@ -6,9 +6,30 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/syndtr/goleveldb/leveldb/opt"
+
+	"github.com/stretchr/testify/require"
 	cmn "github.com/tendermint/tendermint/libs/common"
 )
 
+func TestNewGoLevelDB(t *testing.T) {
+	name := fmt.Sprintf("test_%x", cmn.RandStr(12))
+	// Test write locks
+	db, err := NewGoLevelDB(name, "")
+	require.Nil(t, err)
+	_, err = NewGoLevelDB(name, "")
+	require.NotNil(t, err)
+	db.Close() // Close the db to release the lock
+
+	// Open the db twice in a row to test read-only locks
+	ro1, err := NewGoLevelDBWithOpts(name, "", &opt.Options{ReadOnly: true})
+	defer ro1.Close()
+	require.Nil(t, err)
+	ro2, err := NewGoLevelDBWithOpts(name, "", &opt.Options{ReadOnly: true})
+	defer ro2.Close()
+	require.Nil(t, err)
+}
+
 func BenchmarkRandomReadsWrites(b *testing.B) {
 	b.StopTimer()