# coding=UTF-8
############################################################################################
#
# Author:      Wenguan Ding
# Date:        2025/03/07
# Description: This script is developed to run logical hot backup for mysql database(s)
#
############################################################################################
import os
import subprocess
import time
import gzip
import argparse

# 解析命令行参数
parser = argparse.ArgumentParser(description="MySQL热物理备份脚本")
parser.add_argument("-d", "--database", help="要备份的数据库名称(输入'all'备份所有数据库)", required=True)
parser.add_argument("-p", "--path", help="备份文件存储路径", required=True)
args = parser.parse_args()

# 配置信息
MYSQL_USER = "root"  # MySQL用户名
MYSQL_PASSWORD = "xxxxxxxxxxxx"  # MySQL密码
MYSQL_HOST = "localhost"  # MySQL主机
MYSQL_PORT = "12138"  # MySQL端口

# 创建备份目录（如果不存在）
if not os.path.exists(args.path):
    os.makedirs(args.path)

def backup_database(db_name, backup_dir):
    """备份单个数据库"""
    timestamp = time.strftime("%Y%m%d_%H%M%S")
    backup_file = os.path.join(backup_dir, "{0}_backup_{1}.sql".format(db_name, timestamp))
    compressed_backup_file = backup_file + ".gz"

    try:
        print("开始备份数据库: {0}".format(db_name))
        with open(backup_file, "w") as f:
            subprocess.check_call(
                [
                    "mysqldump",
                    "--user={0}".format(MYSQL_USER),
                    "--password={0}".format(MYSQL_PASSWORD),
                    "--host={0}".format(MYSQL_HOST),
                    "--port={0}".format(MYSQL_PORT),
                    "--single-transaction",  # 确保热备份
                    "--routines",  # 备份存储过程和函数
                    "--triggers",  # 备份触发器
                    "--events",  # 备份事件
                    db_name,
                ],
                stdout=f,
            )
        print("数据库备份成功，文件保存到: {0}".format(backup_file))

        # 压缩备份文件
        with open(backup_file, "rb") as f_in:
            with gzip.open(compressed_backup_file, "wb") as f_out:
                f_out.writelines(f_in)
        print("备份文件已压缩: {0}".format(compressed_backup_file))

        # 删除未压缩的备份文件
        os.remove(backup_file)
        print("已删除未压缩的备份文件: {0}".format(backup_file))

    except subprocess.CalledProcessError as e:
        print("备份失败: {0}".format(e))
    except Exception as e:
        print("发生错误: {0}".format(e))

def get_all_databases():
    """获取所有数据库名称"""
    try:
        output = subprocess.check_output(
            [
                "mysql",
                "--user={0}".format(MYSQL_USER),
                "--password={0}".format(MYSQL_PASSWORD),
                "--host={0}".format(MYSQL_HOST),
                "--port={0}".format(MYSQL_PORT),
                "-e",
                "SHOW DATABASES;",
            ]
        )
        databases = output.splitlines()[1:]  # 跳过第一行标题
        return databases
    except subprocess.CalledProcessError as e:
        print("获取数据库列表失败: {0}".format(e))
        return []

# 执行备份
if args.database.lower() == "all":
    databases = get_all_databases()
    if databases:
        print("开始备份所有数据库: {0}".format(databases))
        for db in databases:
            if db not in ["information_schema", "performance_schema", "mysql", "sys"]:  # 跳过系统数据库
                backup_database(db, args.path)
    else:
        print("未找到可备份的数据库")
else:
    backup_database(args.database, args.path)