type Options struct {
        Dir      string
        ValueDir string

        SyncWrites          bool
        TableLoadingMode    options.FileLoadingMode
        ValueLogLoadingMode options.FileLoadingMode
        NumVersionsToKeep   int
        ReadOnly            bool
        Truncate            bool
        Logger              Logger

        MaxTableSize        int64
        LevelSizeMultiplier int
        MaxLevels           int
        ValueThreshold      int
        NumMemtables        int

        NumLevelZeroTables      int
        NumLevelZeroTablesStall int

        LevelOneSize       int64
        ValueLogFileSize   int64
        ValueLogMaxEntries uint32

        NumCompactors     int
        CompactL0OnClose  bool
        LogRotatesToFlush int32

        // Has unexported fields.
}
    Options are params for creating DB object.

    This package provides DefaultOptions which contains options that should work
    for most applications. Consider using that as a starting point before
    customizing it for your own needs.

    Each option X is documented on the WithX method.

func DefaultOptions(path string) Options
func LSMOnlyOptions(path string) Options
func (opt *Options) Debugf(format string, v ...interface{})
func (opt *Options) Errorf(format string, v ...interface{})
func (opt *Options) Infof(format string, v ...interface{})
func (opt *Options) Warningf(format string, v ...interface{})
func (opt Options) WithCompactL0OnClose(val bool) Options
func (opt Options) WithDir(val string) Options
func (opt Options) WithLevelOneSize(val int64) Options
func (opt Options) WithLevelSizeMultiplier(val int) Options
func (opt Options) WithLogRotatesToFlush(val int32) Options
func (opt Options) WithLogger(val Logger) Options
func (opt Options) WithMaxLevels(val int) Options
func (opt Options) WithMaxTableSize(val int64) Options
func (opt Options) WithNumCompactors(val int) Options
func (opt Options) WithNumLevelZeroTables(val int) Options
func (opt Options) WithNumLevelZeroTablesStall(val int) Options
func (opt Options) WithNumMemtables(val int) Options
func (opt Options) WithNumVersionsToKeep(val int) Options
func (opt Options) WithReadOnly(val bool) Options
func (opt Options) WithSyncWrites(val bool) Options
func (opt Options) WithTableLoadingMode(val options.FileLoadingMode) Options
func (opt Options) WithTruncate(val bool) Options
func (opt Options) WithValueDir(val string) Options
func (opt Options) WithValueLogFileSize(val int64) Options
func (opt Options) WithValueLogLoadingMode(val options.FileLoadingMode) Options
func (opt Options) WithValueLogMaxEntries(val uint32) Options
func (opt Options) WithValueThreshold(val int) Options

$ go doc Options.WithReadOnly
func (opt Options) WithReadOnly(val bool) Options
    WithReadOnly modifies returns a new Options value where ReadOnly has been
    set to the given value. The original Options value is never modified.

    When ReadOnly is true the DB will be opened on read-only mode. Multiple
    processes can open the same Badger DB. Note: if the DB being opened had
    crashed before and has vlog data to be replayed, ReadOnly will cause Open to
    fail with an appropriate message.

    The default value of ReadOnly is false.