經常有一些文件需要在公司和家裡的兩地電腦間手工同步，很麻煩，於是利用七牛雲免費的空間來做服務端實現同步功能。
同時，為了文件內容保密，我採用cryptography模組（通過指定一個複雜的字串）對檔案加密，這樣即使別人獲取了七牛雲上的檔案也無法破解。

import os, time, uuid, requests
from qiniu import Auth, put_file, urlsafe_base64_encode, BucketManager
import qiniu.config
from cryptography.fernet import Fernet
from binascii import
 
 b2a_hex, a2b_hex

class Sync(object):
    def __init__(self, userKey):
        self.fernet = Fernet(b'dUTMoQzCwiamBkwNTGR4AXrw-xxxxxxx=')
        self.qn = Auth('UhzOHyzt0MeL', 'GzTlY7c30WZw')
        self.userKey = userKey
        self.buckName = 'bsync'
        self.tmpFile = os.path.join(os.environ['TEMP'
 
], self.userKey)
        self.bmFile = os.environ['LOCALAPPDATA'] + '\\User Data\\'

    def getRLUT(self):
        '''get remote last update time'''
        bucket = BucketManager(self.qn)
        ret, obj, info = bucket.list(bucket=self.buckName, prefix=self.userKey+'/')
        lastUpdateTime = ''
 

        for i in ret['items']:
            updateTime = i['key'].split('/')[1]
            if updateTime > lastUpdateTime:
                lastUpdateTime = updateTime            
        return lastUpdateTime

    def put(self, timeStr):
        with open(self.bmFile, 'r', encoding='utf8') as f:
            content = self.fernet.encrypt(bytes(f.read(), encoding='utf8'))
        with open(self.tmpFile, 'wb') as f:
            f.write(content)

        fileKey = self.genFileKey(timeStr)
        token = self.qn.upload_token(self.buckName, fileKey, 3600)
        ret, info = put_file(token, fileKey, self.tmpFile)


    def get(self, timeStr):
        fileKey = self.genFileKey(timeStr)
        base_url = 'http://xxxxx.bkt.clouddn.com/%s' % (fileKey)
        private_url = self.qn.private_download_url(base_url, expires=3600)
        resp = requests.get(private_url)
        with open(self.bmFile, 'w', encoding='utf8') as f:
            content = self.fernet.decrypt(resp.content)
            f.write(content.decode('utf8'))

    def genFileKey(self, timeStr):
        return self.userKey + '/' + timeStr

    def run(self):
        if not os.path.exists(self.bmFile):
            return
        remoteLastTimeStr = self.getRLUT()
        localLastTimeStr = time.strftime('%Y%m%d%H%M%S', time.localtime(os.path.getmtime(self.bmFile)))
        if remoteLastTimeStr < localLastTimeStr:
            self.put(localLastTimeStr)
            print("伺服器已更新為最新")
        elif remoteLastTimeStr > localLastTimeStr:
            self.get(remoteLastTimeStr)
            print("本地已更新為最新")
        else:
            print("伺服器與本地狀態同步")

if __name__ == '__main__':
    sb = Sync('test')
    sb.run()