1// Package lock defines the Locker interface and implements the locking logic.
 2package lock
 3
 4import (
 5	"context"
 6	"database/sql"
 7	"errors"
 8)
 9
10var (
11	// ErrLockNotImplemented is returned when the database does not support locking.
12	ErrLockNotImplemented = errors.New("lock not implemented")
13	// ErrUnlockNotImplemented is returned when the database does not support unlocking.
14	ErrUnlockNotImplemented = errors.New("unlock not implemented")
15)
16
17// SessionLocker is the interface to lock and unlock the database for the duration of a session. The
18// session is defined as the duration of a single connection and both methods must be called on the
19// same connection.
20type SessionLocker interface {
21	SessionLock(ctx context.Context, conn *sql.Conn) error
22	SessionUnlock(ctx context.Context, conn *sql.Conn) error
23}