Golang BackupHandle.Directory方法代码示例

// Restore is the main entry point for backup restore.  If there is no
// appropriate backup on the BackupStorage, Restore logs an error
// and returns ErrNoBackup. Any other error is returned.
func Restore(
	ctx context.Context,
	mysqld MysqlDaemon,
	dir string,
	restoreConcurrency int,
	hookExtraEnv map[string]string,
	localMetadata map[string]string,
	logger logutil.Logger,
	deleteBeforeRestore bool) (replication.Position, error) {

	// find the right backup handle: most recent one, with a MANIFEST
	logger.Infof("Restore: looking for a suitable backup to restore")
	bs, err := backupstorage.GetBackupStorage()
	if err != nil {
		return replication.Position{}, err
	}
	defer bs.Close()
	bhs, err := bs.ListBackups(dir)
	if err != nil {
		return replication.Position{}, fmt.Errorf("ListBackups failed: %v", err)
	}
	var bh backupstorage.BackupHandle
	var bm BackupManifest
	var toRestore int
	for toRestore = len(bhs) - 1; toRestore >= 0; toRestore-- {
		bh = bhs[toRestore]
		rc, err := bh.ReadFile(backupManifest)
		if err != nil {
			log.Warningf("Possibly incomplete backup %v in directory %v on BackupStorage: can't read MANIFEST: %v)", bh.Name(), dir, err)
			continue
		}

		err = json.NewDecoder(rc).Decode(&bm)
		rc.Close()
		if err != nil {
			log.Warningf("Possibly incomplete backup %v in directory %v on BackupStorage (cannot JSON decode MANIFEST: %v)", bh.Name(), dir, err)
			continue
		}

		logger.Infof("Restore: found backup %v %v to restore with %v files", bh.Directory(), bh.Name(), len(bm.FileEntries))
		break
	}
	if toRestore < 0 {
		logger.Errorf("No backup to restore on BackupStorage for directory %v. Starting up empty.", dir)
		if err = populateLocalMetadata(mysqld, localMetadata); err == nil {
			err = ErrNoBackup
		}
		return replication.Position{}, err
	}

	if !deleteBeforeRestore {
		logger.Infof("Restore: checking no existing data is present")
		ok, err := checkNoDB(ctx, mysqld)
		if err != nil {
			return replication.Position{}, err
		}
		if !ok {
			logger.Infof("Auto-restore is enabled, but mysqld already contains data. Assuming vttablet was just restarted.")
			if err = populateLocalMetadata(mysqld, localMetadata); err == nil {
				err = ErrExistingDB
			}
			return replication.Position{}, err
		}
	}

	logger.Infof("Restore: shutdown mysqld")
	err = mysqld.Shutdown(ctx, true)
	if err != nil {
		return replication.Position{}, err
	}

	logger.Infof("Restore: deleting existing files")
	if err := removeExistingFiles(mysqld.Cnf()); err != nil {
		return replication.Position{}, err
	}

	logger.Infof("Restore: reinit config file")
	err = mysqld.ReinitConfig(ctx)
	if err != nil {
		return replication.Position{}, err
	}

	logger.Infof("Restore: copying all files")
	if err := restoreFiles(mysqld.Cnf(), bh, bm.FileEntries, restoreConcurrency); err != nil {
		return replication.Position{}, err
	}

	// mysqld needs to be running in order for mysql_upgrade to work.
	// If we've just restored from a backup from previous MySQL version then mysqld
	// may fail to start due to a different structure of mysql.* tables. The flag
	// --skip-grant-tables ensures that these tables are not read until mysql_upgrade
	// is executed. And since with --skip-grant-tables anyone can connect to MySQL
	// without password, we are passing --skip-networking to greatly reduce the set
	// of those who can connect.
	logger.Infof("Restore: starting mysqld for mysql_upgrade")
	err = mysqld.Start(ctx, "--skip-grant-tables", "--skip-networking")
	if err != nil {
//.........这里部分代码省略.........

// Restore is the main entry point for backup restore.  If there is no
// appropriate backup on the BackupStorage, Restore logs an error
// and returns ErrNoBackup. Any other error is returned.
func Restore(ctx context.Context, mysqld MysqlDaemon, dir string, restoreConcurrency int, hookExtraEnv map[string]string) (replication.Position, error) {
	// find the right backup handle: most recent one, with a MANIFEST
	log.Infof("Restore: looking for a suitable backup to restore")
	bs, err := backupstorage.GetBackupStorage()
	if err != nil {
		return replication.Position{}, err
	}
	defer bs.Close()
	bhs, err := bs.ListBackups(dir)
	if err != nil {
		return replication.Position{}, fmt.Errorf("ListBackups failed: %v", err)
	}
	var bh backupstorage.BackupHandle
	var bm BackupManifest
	var toRestore int
	for toRestore = len(bhs) - 1; toRestore >= 0; toRestore-- {
		bh = bhs[toRestore]
		rc, err := bh.ReadFile(backupManifest)
		if err != nil {
			log.Warningf("Possibly incomplete backup %v in directory %v on BackupStorage: can't read MANIFEST: %v)", bh.Name(), dir, err)
			continue
		}

		err = json.NewDecoder(rc).Decode(&bm)
		rc.Close()
		if err != nil {
			log.Warningf("Possibly incomplete backup %v in directory %v on BackupStorage (cannot JSON decode MANIFEST: %v)", bh.Name(), dir, err)
			continue
		}

		log.Infof("Restore: found backup %v %v to restore with %v files", bh.Directory(), bh.Name(), len(bm.FileEntries))
		break
	}
	if toRestore < 0 {
		log.Errorf("No backup to restore on BackupStorage for directory %v", dir)
		return replication.Position{}, ErrNoBackup
	}

	log.Infof("Restore: checking no existing data is present")
	ok, err := checkNoDB(ctx, mysqld)
	if err != nil {
		return replication.Position{}, err
	}
	if !ok {
		return replication.Position{}, ErrExistingDB
	}

	log.Infof("Restore: shutdown mysqld")
	err = mysqld.Shutdown(ctx, true)
	if err != nil {
		return replication.Position{}, err
	}

	log.Infof("Restore: deleting existing files")
	if err := removeExistingFiles(mysqld.Cnf()); err != nil {
		return replication.Position{}, err
	}

	log.Infof("Restore: copying all files")
	if err := restoreFiles(mysqld.Cnf(), bh, bm.FileEntries, restoreConcurrency); err != nil {
		return replication.Position{}, err
	}

	// mysqld needs to be running in order for mysql_upgrade to work.
	log.Infof("Restore: starting mysqld for mysql_upgrade")
	err = mysqld.Start(ctx)
	if err != nil {
		return replication.Position{}, err
	}

	log.Infof("Restore: running mysql_upgrade")
	if err := mysqld.RunMysqlUpgrade(); err != nil {
		return replication.Position{}, fmt.Errorf("mysql_upgrade failed: %v", err)
	}

	// The MySQL manual recommends restarting mysqld after running mysql_upgrade,
	// so that any changes made to system tables take effect.
	log.Infof("Restore: restarting mysqld after mysql_upgrade")
	err = mysqld.Shutdown(ctx, true)
	if err != nil {
		return replication.Position{}, err
	}
	err = mysqld.Start(ctx)
	if err != nil {
		return replication.Position{}, err
	}

	return bm.Position, nil
}