所以我做了一个小技巧，TimedRotatingFileHandler以便能够在时间和大小之后进行翻转。我不得不修改__init__、shouldRollover和doRollover（getFilesToDelete见下文）。这是结果，当我设置when='M'，interval=2，backupCount=20，maxBytes=1048576时：
-rw-r--r-- 1 user group 185164 Jun 10 00:54 sumid.log
-rw-r--r-- 1 user group 1048462 Jun 10 00:48 sumid.log.2011-06-10_00-48.001
-rw-r--r-- 1 user group 1048464 Jun 10 00:48 sumid.log.2011-06-10_00-48.002
-rw-r--r-- 1 user group 1048533 Jun 10 00:49 sumid.log.2011-06-10_00-48.003
-rw-r--r-- 1 user group 1048544 Jun 10 00:50 sumid.log.2011-06-10_00-49.001
-rw-r--r-- 1 user group 574362 Jun 10 00:52 sumid.log.2011-06-10_00-50.001
您可以看到前四个日志在达到 1MB 大小后被翻转，而最后一个翻转发生在两分钟后。到目前为止，我没有测试删除旧日志文件，所以它可能不起作用。该代码肯定不适用于 backupCount>=1000。我只在文件名的末尾附加了三位数字。
这是修改后的代码：
class EnhancedRotatingFileHandler(logging.handlers.TimedRotatingFileHandler):
def __init__(self, filename, when='h', interval=1, backupCount=0, encoding=None, delay=0, utc=0, maxBytes=0):
""" This is just a combination of TimedRotatingFileHandler and RotatingFileHandler (adds maxBytes to TimedRotatingFileHandler) """
logging.handlers.TimedRotatingFileHandler.__init__(self, filename, when, interval, backupCount, encoding, delay, utc)
self.maxBytes=maxBytes
def shouldRollover(self, record):
"""
Determine if rollover should occur.
Basically, see if the supplied record would cause the file to exceed
the size limit we have.
we are also comparing times
"""
if self.stream is None: # delay was set...
self.stream = self._open()
if self.maxBytes > 0: # are we rolling over?
msg = "%s\n" % self.format(record)
self.stream.seek(0, 2) #due to non-posix-compliant Windows feature
if self.stream.tell() + len(msg) >= self.maxBytes:
return 1
t = int(time.time())
if t >= self.rolloverAt:
return 1
#print "No need to rollover: %d, %d" % (t, self.rolloverAt)
return 0
def doRollover(self):
"""
do a rollover; in this case, a date/time stamp is appended to the filename
when the rollover happens. However, you want the file to be named for the
start of the interval, not the current time. If there is a backup count,
then we have to get a list of matching filenames, sort them and remove
the one with the oldest suffix.
"""
if self.stream:
self.stream.close()
# get the time that this sequence started at and make it a TimeTuple
currentTime = int(time.time())
dstNow = time.localtime(currentTime)[-1]
t = self.rolloverAt - self.interval
if self.utc:
timeTuple = time.gmtime(t)
else:
timeTuple = time.localtime(t)
dstThen = timeTuple[-1]
if dstNow != dstThen:
if dstNow:
addend = 3600
else:
addend = -3600
timeTuple = time.localtime(t + addend)
dfn = self.baseFilename + "." + time.strftime(self.suffix, timeTuple)
if self.backupCount > 0:
cnt=1
dfn2="%s.%03d"%(dfn,cnt)
while os.path.exists(dfn2):
dfn2="%s.%03d"%(dfn,cnt)
cnt+=1
os.rename(self.baseFilename, dfn2)
for s in self.getFilesToDelete():
os.remove(s)
else:
if os.path.exists(dfn):
os.remove(dfn)
os.rename(self.baseFilename, dfn)
#print "%s -> %s" % (self.baseFilename, dfn)
self.mode = 'w'
self.stream = self._open()
newRolloverAt = self.computeRollover(currentTime)
while newRolloverAt <= currentTime:
newRolloverAt = newRolloverAt + self.interval
#If DST changes and midnight or weekly rollover, adjust for this.
if (self.when == 'MIDNIGHT' or self.when.startswith('W')) and not self.utc:
dstAtRollover = time.localtime(newRolloverAt)[-1]
if dstNow != dstAtRollover:
if not dstNow: # DST kicks in before next rollover, so we need to deduct an hour
addend = -3600
else: # DST bows out before next rollover, so we need to add an hour
addend = 3600
newRolloverAt += addend
self.rolloverAt = newRolloverAt
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:-4]
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