之前有写利用md5方式来做差异备份,但是这种md5方式来写存在以下问题:
- md5sum获取有些软连接的MD5值存在问题
- 不支持对空目录进行备份,因为md5sum无法获取空目录的md5值
- 权限的修改md5sum无法判断
解决方案:
利用文件的mtime ctime
mtime(Modified time)是在写入文件时随文件内容的更改而更改的
ctime(Create time)是在写入文件、更改所有者、权限或链接设置时随Inode的内容更改而更改的
废话不多说直接上代码:
- #!/usr/bin/env python
- import time,os,sys,cPickle
- fileInfo = {}
- def logger(time,fileName,status,fileNum):
- f = open('backup.log','a')
- f.write("%s\t%s\t%s\t\t%s\n" % (time,fileName,status,fileNum))
- def tar(sDir,dDir,fileNum):
- command = "tar zcf %s %s >/dev/null 2>&1" % (dDir + ".tar.gz",sDir)
- if os.system(command) == 0:
- logger(time.strftime('%F %X'),dDir + ".tar.gz",'success',fileNum)
- else:
- logger(time.strftime('%F %X'),dDir + ".tar.gz",'failed',fileNum)
- def fullBak(path):
- fileNum = 0
- for root,dirs,files in os.walk(path):
- for name in files:
- file = os.path.join(root, name)
- mtime = os.path.getmtime(file)
- ctime = os.path.getctime(file)
- fileInfo[file] = (mtime,ctime)
- fileNum += 1
- f = open(P,'w')
- cPickle.dump(fileInfo,f)
- f.close()
- tar(S,D,fileNum)
- def diffBak(path):
- for root,dirs,files in os.walk(path):
- for name in files:
- file = os.path.join(root,name)
- mtime = os.path.getmtime(file)
- ctime = os.path.getctime(file)
- fileInfo[file] = (mtime,ctime)
- if os.path.isfile(P) == 0:
- f = open(P,'w')
- f.close()
- if os.stat(P).st_size == 0:
- f = open(P,'w')
- cPickle.dump(fileInfo,f)
- fileNum = len(fileInfo.keys())
- f.close()
- print fileNum
- tar(S,D,fileNum)
- else:
- f = open(P)
- old_fileInfo = cPickle.load(f)
- f.close()
- difference = dict(set(fileInfo.items())^set(old_fileInfo.items()))
- fileNum = len(difference)
- print fileNum
- difference_file = ' '.join(difference.keys())
- print difference_file
- tar(difference_file,D,fileNum)
- f = open(P,'w')
- cPickle.dump(fileInfo,f)
- f.close()
- def Usage():
- print '''
- Syntax: python file_bakcup.py pickle_file model source_dir filename_bk
- model: 1:Full backup 2:Differential backup
- example: python file_backup.py fileinfo.pk 2 /etc etc_$(date +%F)
- explain: Automatically add '.tar.gz' suffix
- '''
- sys.exit()
- if len(sys.argv) != 5:
- Usage()
- P = sys.argv[1]
- M = int(sys.argv[2])
- S = sys.argv[3]
- D = sys.argv[4]
- if M == 1:
- fullBak(S)
- elif M == 2:
- diffBak(S)
- else:
- print "\033[;31mDoes not support this mode\033[0m"
- Usage()
测试:
- $ python file_backup.py data.pk 1 data data_$(date +%F) #全备份
- $ > data/www.linuxeye.com #测试创建文件,修改文件权限
- $ chmod 777 data/py/eshop_bk/data.db
- $ python file_backup.py data.pk 2 data data_$(date +%F)_1 #备份改变的文件
- 2
- data/py/eshop_bk/data.db data/www.linuxeye.com
Mon Oct 28 16:32:23 CST 2013