项目使用了 logging 的 TimedRotatingFileHandler :
- #!/user/bin/env python
- # -*- coding: utf-8 -*-
- import logging
- from logging.handlers import TimedRotatingFileHandler
- log = logging.getLogger()
- file_name = "./test.log"
- logformatter = logging.Formatter('%(asctime)s [%(levelname)s]|%(message)s')
- loghandle = TimedRotatingFileHandler(file_name, 'midnight', 1, 2)
- loghandle.setFormatter(logformatter)
- loghandle.suffix = '%Y%m%d'
- log.addHandler(loghandle)
- log.setLevel(logging.DEBUG)
- log.debug("init successful")
参考 python logging 的官方文档:
https://docs.python.org/2/library/logging.html
查看其 入门 实例, 可以看到使用按时间轮转的相关内容:
- import logging
- # create logger
- logger = logging.getLogger('simple_example')
- logger.setLevel(logging.DEBUG)
- # create console handler and set level to debug
- ch = logging.StreamHandler()
- ch.setLevel(logging.DEBUG)
- # create formatter
- formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
- # add formatter to ch
- ch.setFormatter(formatter)
- # add ch to logger
- logger.addHandler(ch)
- # 'application' code
- logger.debug('debug message')
粗看下, 也看不出有什么不对的地方.
那就看下 logging 的代码, 找到 TimedRotatingFileHandler 相关的内容, 其中删除过期日志的内容:
- logging/handlers.py
- def getFilesToDelete(self):
- """
Determine the files to delete when rolling over.
More specific than the earlier method, which just used glob.glob().
- """
- dirName, baseName = os.path.split(self.baseFilename)
- fileNames = os.listdir(dirName)
- result = []
- prefix = baseName + "."
- plen = len(prefix)
- for fileName in fileNames:
- if fileName[:plen] == prefix:
- suffix = fileName[plen:]
- if self.extMatch.match(suffix):
- result.append(os.path.join(dirName, fileName))
- result.sort()
- if len(result) < self.backupCount:
- result = []
- else:
- result = result[:len(result) - self.backupCount]
- return result
轮转删除的原理, 是查找到日志目录下, 匹配 suffix 后缀的文件, 加入到删除列表, 如果超过了指定的数目就加入到要删除的列表中, 再看下匹配的原理:
- elif self.when == 'D' or self.when == 'MIDNIGHT':
- self.interval = 60 * 60 * 24 # one day
- self.suffix = "%Y-%m-%d"
- self.extMatch = r"^\d{4}-\d{2}-\d{2}$"
exMatch 是一个正则的匹配, 格式是 - 分隔的时间, 而我们自己设置了新的 suffix 没有 - 分隔:
loghandle.suffix = '%Y%m%d'
这样就找不到要删除的文件, 不会删除相关的日志.
来源: http://www.bubuko.com/infodetail-2583720.html