// Copyright (c) 2015-2021 MinIO, Inc.//// This file is part of MinIO Object Storage stack//// This program is free software: you can redistribute it and/or modify// it under the terms of the GNU Affero General Public License as published by// the Free Software Foundation, either version 3 of the License, or// (at your option) any later version.//// This program is distributed in the hope that it will be useful// but WITHOUT ANY WARRANTY; without even the implied warranty of// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the// GNU Affero General Public License for more details.//// You should have received a copy of the GNU Affero General Public License// along with this program.  If not, see <http://www.gnu.org/licenses/>. package dsync import "context" // NetLocker is dsync compatible locker interface.type NetLocker interface {	// Do read lock for given LockArgs.  It should return	// * a boolean to indicate success/failure of the operation	// * an error on failure of lock request operation.	RLock(ctx context.Context, args LockArgs) (bool, error) 	// Do write lock for given LockArgs. It should return	// * a boolean to indicate success/failure of the operation	// * an error on failure of lock request operation.	Lock(ctx context.Context, args LockArgs) (bool, error) 	// Do read unlock for given LockArgs. It should return	// * a boolean to indicate success/failure of the operation	// * an error on failure of unlock request operation.	// Canceling the context will abort the remote call.	// In that case, the resource may or may not be unlocked.	RUnlock(ctx context.Context, args LockArgs) (bool, error) 	// Do write unlock for given LockArgs. It should return	// * a boolean to indicate success/failure of the operation	// * an error on failure of unlock request operation.	// Canceling the context will abort the remote call.	// In that case, the resource may or may not be unlocked.	Unlock(ctx context.Context, args LockArgs) (bool, error) 	// Refresh the given lock to prevent it from becoming stale	Refresh(ctx context.Context, args LockArgs) (bool, error) 	// Unlock (read/write) forcefully for given LockArgs. It should return	// * a boolean to indicate success/failure of the operation	// * an error on failure of unlock request operation.	ForceUnlock(ctx context.Context, args LockArgs) (bool, error) 	// Returns underlying endpoint of this lock client instance.	String() string 	// Close closes any underlying connection to the service endpoint	Close() error 	// Is the underlying connection online? (is always true for any local lockers)	IsOnline() bool 	// Is the underlying locker local to this server?	IsLocal() bool}