github.com/1aal/kubeblocks@v0.0.0-20231107070852-e1c03e598921/pkg/lorry/engines/polardbx/get_replica_role.go (about)

     1  /*
     2  Copyright (C) 2022-2023 ApeCloud Co., Ltd
     3  
     4  This file is part of KubeBlocks project
     5  
     6  This program is free software: you can redistribute it and/or modify
     7  it under the terms of the GNU Affero General Public License as published by
     8  the Free Software Foundation, either version 3 of the License, or
     9  (at your option) any later version.
    10  
    11  This program is distributed in the hope that it will be useful
    12  but WITHOUT ANY WARRANTY; without even the implied warranty of
    13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    14  GNU Affero General Public License for more details.
    15  
    16  You should have received a copy of the GNU Affero General Public License
    17  along with this program.  If not, see <http://www.gnu.org/licenses/>.
    18  */
    19  
    20  package polardbx
    21  
    22  import (
    23  	"context"
    24  
    25  	"github.com/pkg/errors"
    26  )
    27  
    28  func (mgr *Manager) GetReplcaRole(ctx context.Context) (string, error) {
    29  	sql := "select role from information_schema.alisql_cluster_local"
    30  
    31  	rows, err := mgr.DB.QueryContext(ctx, sql)
    32  	if err != nil {
    33  		mgr.Logger.Error(err, "error executing sql", "sql", sql)
    34  		return "", errors.Wrapf(err, "error executing %s", sql)
    35  	}
    36  
    37  	defer func() {
    38  		_ = rows.Close()
    39  		_ = rows.Err()
    40  	}()
    41  
    42  	var role string
    43  	var isReady bool
    44  	for rows.Next() {
    45  		if err = rows.Scan(&role); err != nil {
    46  			mgr.Logger.Error(err, "Role query error")
    47  			return role, err
    48  		}
    49  		isReady = true
    50  	}
    51  	if isReady {
    52  		return role, nil
    53  	}
    54  	return "", errors.Errorf("exec sql %s failed: no data returned", sql)
    55  }