用python压缩（存档）旧日志文件

Question

我正在使用Python中的standart logger库。有RotatingFileHandler，例如，它可以每天旋转日志文件。

但它只是重新命名。如果它不仅可以重命名，还可以将旧文件放入zip（或gz、bzip等）存档，那就太好了。

有什么简单的方法可以做到这一点吗？

Answer 1

接受的答案将只存档一个文件-（basefile.log.1）。其他文件不存档。 此代码将存档除基本文件以外的所有日志文件。

import os
import gzip
import logging.handlers

class NewRotatingFileHandler(logging.handlers.RotatingFileHandler):
    def __init__(self, filename, **kws):
        backupCount = kws.get('backupCount', 0)
        self.backup_count = backupCount
        logging.handlers.RotatingFileHandler.__init__(self, filename, **kws)

    def doArchive(self, old_log):
        with open(old_log) as log:
            with gzip.open(old_log + '.gz', 'wb') as comp_log:
                comp_log.writelines(log)
       os.remove(old_log)

   def doRollover(self):
      if self.stream:
          self.stream.close()
          self.stream = None
      if self.backup_count > 0:
          for i in range(self.backup_count - 1, 0, -1):
              sfn = "%s.%d.gz" % (self.baseFilename, i)
              dfn = "%s.%d.gz" % (self.baseFilename, i + 1)
              if os.path.exists(sfn):
                  if os.path.exists(dfn):
                      os.remove(dfn)
                  os.rename(sfn, dfn)
      dfn = self.baseFilename + ".1"
      if os.path.exists(dfn):
          os.remove(dfn)
      if os.path.exists(self.baseFilename):
          os.rename(self.baseFilename, dfn)
          self.doArchive(dfn)
      if not self.delay:
          self.stream = self._open()

Answer 2

通过使用encoding='bz2-codec'初始化RotatingFileHandler，可以自动写入bz2压缩日志文件：

import logging
import logging.handlers as handlers

if __name__=='__main__':
    log_filename='log_rotate.bz2'
    logger = logging.getLogger(__name__)
    logger.setLevel(logging.DEBUG)
    handler = handlers.RotatingFileHandler(
        log_filename, maxBytes=20, backupCount=5, encoding='bz2-codec')
    logger.addHandler(handler)
    for i in range(20):
        logger.debug('i = %d' % i)

PS.Python3 removed 'bz2-codec'来自一组有效的编码，所以这个解决方案是Python2特有的。

Answer 3

我认为您最好的选择是扩展RotatingFileHandler这样的内容（未测试）：

import os
from logging.handlers import RotatingFileHandler


COMPRESSION_SUPPORTED = {}

try:
   import gzip
   COMPRESSION_SUPPORTED['gz'] = gzip
except ImportError:
   pass

try:
   import zipfile
   COMPRESSION_SUPPORTED['zip'] = zipfile
except ImportError:
   pass


class NewRotatingFileHandler(RotatingFileHandler):

     def __init__(self, *args, **kws):
         compress_mode = kws.pop('compress_mode')

         try:
             self.compress_cls = COMPRESSION_SUPPORTED[compress_mode]
         except KeyError:
             raise ValueError('"%s" compression method not supported.' % compress_mode)

         super(NewRotatingFileHandler, self).__init__(self, *args, **kws)

     def doRollover(self):
         super(NewRotatingFileHandler, self).doRollover()

         # Compress the old log.
         old_log = self.baseFilename + ".1"
         with open(old_log) as log:
             with self.compress_cls.open(old_log + '.gz', 'wb') as comp_log:
                 comp_log.writelines(log)

         os.remove(old_log)