from aliyunsdkcore.client import AcsClient
from aliyunsdkrds.request.v20140815 import DescribeBinlogFilesRequest

import hashlib
import json
import requests
import datetime
import logging
import os
from urllib.request import urlopen

logging.basicConfig(level=logging.INFO, format="%(asctime)s %(message)s")
class Rds_Bakup:
    def __init__(self):
        self.access_key_id = "xxxxxxxxx"
        self.access_key_secret="xxxxxxxxxxxxx"
        self.region_id="cn-beijing"
        self.db_id="xxxxxxxx"
        self.product_code='RDS'
        self.star_time = (datetime.datetime.utcnow() - datetime.timedelta(days=1)).strftime('%Y-%m-%dT%H:%M:%SZ')
        self.end_time = datetime.datetime.utcnow().strftime('%Y-%m-%dT%H:%M:%SZ')
        self.accept_format = "json"
        self.accept_name = "DescribeBinlogFiles"
        self.page_size = 100
        self.page_num = 1
        self.rds_bakup_info = {}
        self.bakup_time = datetime.datetime.now().strftime('%Y-%m-%d')
        self.rds_bakup_dir = "/data/rdsbak/binlog/{}".format(self.bakup_time)
        if not os.path.exists(self.rds_bakup_dir):
            os.mkdir(self.rds_bakup_dir)

    def client_request(self):
        client = AcsClient(self.access_key_id, self.access_key_secret, self.region_id)
        request = DescribeBinlogFilesRequest.DescribeBinlogFilesRequest()
        request.set_accept_format(self.accept_format)
        request.set_action_name(self.accept_name)
        request.set_DBInstanceId(self.db_id)
        request.set_StartTime(self.star_time)
        request.set_EndTime(self.end_time)
        request.set_PageSize(self.page_size)
        request.set_PageNumber(self.page_num)

        return client, request


    def rds_down(self):

        result = self.client_request()[0].do_action_with_exception(self.client_request()[1]).decode()
        s=json.loads(result)

        for bak_item in s['Items']['BinLogFile']:
            file_down_url = bak_item.get('IntranetDownloadLink')
            file_name = "{}-{}-{}-{}".format(bak_item.get('HostInstanceID'), bak_item.get('LogBeginTime'), bak_item.get('LogEndTime'), bak_item.get('LogFileName')).replace(':', '_')
            print(file_name, file_down_url)
            req = urlopen(file_down_url)

            log_file = "{0}/{1}_down.log".format(self.rds_bakup_dir, file_name)
            file_handle = logging.FileHandler(log_file, encoding='utf-8')
            self.logger = logging.getLogger(log_file)
            self.logger.addHandler(file_handle)
            chunk = 32 * 1024

            try:
                with open('{}/{}'.format(self.rds_bakup_dir, file_name), 'wb') as fobj:
                    while True:
                        data = req.read(chunk)
                        if not data:
                            break

                        fobj.write(data)
                    self.logger.info("下载成功 {}".format(bak_item))

                sha_file = "{0}/{1}.SHA256".format(self.rds_bakup_dir, file_name)
                sha_handle = logging.FileHandler(sha_file, encoding='utf-8')
                self.logger = logging.getLogger(sha_file)
                self.logger.addHandler(sha_handle)
                hash_digest = hashlib.sha256()

                with open('{}/{}'.format(self.rds_bakup_dir, file_name), 'rb') as hobj:
                    hash_digest.update(hobj.read())

                self.logger.info("SHA256: {}".format(hash_digest.hexdigest()))

            except Exception as e:
                self.logger.info("下载出错 {}".format(e))

if __name__ == '__main__':
    getfile = Rds_Bakup()
    try:
        getfile.rds_down()
    except Exception as e:
        logging.info("下载出错 {}".format(e))