Code review and small optimizations, prepared to provide offset-based time zones for date-detectors (parsing of input-string)

fail2ban/server/datedetector.py

@@ -27,6 +27,7 @@ import time
 from threading import Lock
 
 from .datetemplate import re, DateTemplate, DatePatternRegex, DateTai64n, DateEpoch
+from .strptime import validateTimeZone
 from .utils import Utils
 from ..helpers import getLogger
 
@@ -222,6 +223,8 @@ class DateDetector(object):
 		self.__firstUnused = 0
 		# pre-match pattern:
 		self.__preMatch = None
+		# default TZ (if set, treat log lines without explicit time zone to be in this time zone):
+		self.__default_tz = None
 
 	def _appendTemplate(self, template, ignoreDup=False):
 		name = template.name
@@ -423,7 +426,15 @@ class DateDetector(object):
 		logSys.log(logLevel, " no template.")
 		return (None, None)
 
-	def getTime(self, line, timeMatch=None, default_tz=None):
+	@property
+	def default_tz(self):
+		return self.__default_tz
+
+	@default_tz.setter
+	def default_tz(self, value):
+		self.__default_tz = validateTimeZone(value)
+
+	def getTime(self, line, timeMatch=None):
 		"""Attempts to return the date on a log line using templates.
 
 		This uses the templates' `getDate` method in an attempt to find
@@ -449,7 +460,7 @@ class DateDetector(object):
 		template = timeMatch[1]
 		if template is not None:
 			try:
-				date = template.getDate(line, timeMatch[0], default_tz=default_tz)
+				date = template.getDate(line, timeMatch[0], default_tz=self.__default_tz)
 				if date is not None:
 					if logSys.getEffectiveLevel() <= logLevel: # pragma: no cover - heavy debug
 						logSys.log(logLevel, "  got time %f for %r using template %s",

fail2ban/server/filter.py

@@ -34,13 +34,12 @@ from .failmanager import FailManagerEmpty, FailManager
 from .ipdns import DNSUtils, IPAddr
 from .ticket import FailTicket
 from .jailthread import JailThread
-from .datedetector import DateDetector
+from .datedetector import DateDetector, validateTimeZone
 from .mytime import MyTime
 from .failregex import FailRegex, Regex, RegexException
 from .action import CommandAction
 from .utils import Utils
 from ..helpers import getLogger, PREFER_ENC
-from .strptime import validateTimeZone
 
 # Gets the instance of the logger.
 logSys = getLogger(__name__)
@@ -88,6 +87,8 @@ class Filter(JailThread):
 		## Store last time stamp, applicable for multi-line
 		self.__lastTimeText = ""
 		self.__lastDate = None
+		## if set, treat log lines without explicit time zone to be in this time zone
+		self.__logtimezone = None
 		## External command
 		self.__ignoreCommand = False
 		## Default or preferred encoding (to decode bytes from file or journal):
@@ -103,8 +104,6 @@ class Filter(JailThread):
 		self.checkAllRegex = False
 		## if true ignores obsolete failures (failure time < now - findTime):
 		self.checkFindTime = True
-		## if set, treat log lines without explicit time zone to be in this time zone
-		self.logtimezone = None
 		## Ticks counter
 		self.ticks = 0
 
@@ -285,6 +284,7 @@ class Filter(JailThread):
 			return
 		else:
 			dd = DateDetector()
+			dd.default_tz = self.__logtimezone
 			if not isinstance(pattern, (list, tuple)):
 				pattern = filter(bool, map(str.strip, re.split('\n+', pattern)))
 			for pattern in pattern:
@@ -316,7 +316,9 @@ class Filter(JailThread):
 	# @param tz the symbolic timezone (for now fixed offset only: UTC[+-]HHMM)
 
 	def setLogTimeZone(self, tz):
-		self.logtimezone = validateTimeZone(tz)
+		validateTimeZone(tz); # avoid setting of wrong value, but hold original
+		self.__logtimezone = tz
+		if self.dateDetector: self.dateDetector.default_tz = self.__logtimezone
 
 	##
 	# Get the log default timezone
@@ -324,7 +326,7 @@ class Filter(JailThread):
 	# @return symbolic timezone (a string)
 
 	def getLogTimeZone(self):
-		return self.logtimezone
+		return self.__logtimezone
 
 	##
 	# Set the maximum retry value.
@@ -640,8 +642,7 @@ class Filter(JailThread):
 			self.__lastDate = date
 		elif timeText:
 
-			dateTimeMatch = self.dateDetector.getTime(timeText, tupleLine[3],
-								  default_tz=self.logtimezone)
+			dateTimeMatch = self.dateDetector.getTime(timeText, tupleLine[3])
 
 			if dateTimeMatch is None:
 				logSys.error("findFailure failed to parse timeText: %s", timeText)
@@ -994,8 +995,7 @@ class FileFilter(Filter):
 				if timeMatch:
 					dateTimeMatch = self.dateDetector.getTime(
 						line[timeMatch.start():timeMatch.end()],
-						(timeMatch, template),
-						default_tz=self.logtimezone)
+						(timeMatch, template))
 				else:
 					nextp = container.tell()
 					if nextp > maxp:

fail2ban/server/strptime.py

@@ -27,7 +27,7 @@ from .mytime import MyTime
 
 locale_time = LocaleTime()
 timeRE = TimeRE()
-FIXED_OFFSET_TZ_RE = re.compile(r'UTC(([+-]\d{2})(\d{2}))?$')
+FIXED_OFFSET_TZ_RE = re.compile(r'(?:Z|UTC|GMT)?([+-]\d{2}(?:\d{2}))?$')
 
 def _getYearCentRE(cent=(0,3), distance=3, now=(MyTime.now(), MyTime.alternateNow)):
 	""" Build century regex for last year and the next years (distance).
@@ -84,30 +84,33 @@ def getTimePatternRE():
 def validateTimeZone(tz):
 	"""Validate a timezone.
 
-	For now this accepts only the UTC[+-]hhmm format.
+	For now this accepts only the UTC[+-]hhmm format (UTC has aliases GMT/Z and optional).
 	In the future, it may be extended for named time zones (such as Europe/Paris)
         present on the system, if a suitable tz library is present.
 	"""
+	if tz is None:
+		return None
 	m = FIXED_OFFSET_TZ_RE.match(tz)
 	if m is None:
 		raise ValueError("Unknown or unsupported time zone: %r" % tz)
-	return tz
+	tz = m.group(1)
+	if tz is None or tz == '': # UTC/GMT
+		return 0; # fixed zero offzet
+	return zone2offset(tz, 0)
 
 def zone2offset(tz, dt):
 	"""Return the proper offset, in minutes according to given timezone at a given time.
 
 	Parameters
 	----------
-	tz: symbolic timezone (for now only UTC[+-]hhmm is supported, and it's assumed to have
-                               been validated already)
-        dt: datetime instance for offset computation
+	tz: symbolic timezone or offset (for now only [+-]hhmm is supported, and it's assumed to have
+		been validated already)
+	dt: datetime instance for offset computation
 	"""
-	if tz == 'UTC':
-		return 0
-	unsigned = int(tz[4:6])*60 + int(tz[6:])
-	if tz[3] == '-':
-		return -unsigned
-	return unsigned
+	if isinstance(tz, basestring):
+		# [+-]1 * (hh*60 + mm)
+		return int(tz[0]+'1') * (int(tz[1:3])*60 + int(tz[3:5]))
+	return tz
 
 def reGroupDictStrptime(found_dict, msec=False, default_tz=None):
 	"""Return time from dictionary of strptime fields

fail2ban/tests/datedetectortestcase.py

@@ -91,19 +91,24 @@ class DateDetectorTest(LogCaptureTestCase):
 
 	def testDefaultTimeZone(self):
 		log = "2017-01-23 15:00:00"
-		datelog, _ = self.datedetector.getTime(log, default_tz='UTC+0300')
+		dd = self.datedetector
+		dd.default_tz='UTC+0300'; datelog, _ = dd.getTime(log)
 		# so in UTC, it was noon
 		self.assertEqual(datetime.datetime.utcfromtimestamp(datelog),
 				 datetime.datetime(2017, 1, 23, 12, 0, 0))
 
-		datelog, _ = self.datedetector.getTime(log, default_tz='UTC')
+		dd.default_tz='UTC'; datelog, _ = dd.getTime(log)
 		self.assertEqual(datetime.datetime.utcfromtimestamp(datelog),
 				 datetime.datetime(2017, 1, 23, 15, 0, 0))
+		self.assertEqual(dd.default_tz, 0); # utc == 0
 
-		datelog, _ = self.datedetector.getTime(log, default_tz='UTC-0430')
+		dd.default_tz='UTC-0430'; datelog, _ = dd.getTime(log)
 		self.assertEqual(datetime.datetime.utcfromtimestamp(datelog),
 				 datetime.datetime(2017, 1, 23, 19, 30, 0))
 
+		self.assertRaises(ValueError, setattr, dd, 'default_tz', 'WRONG-TZ')
+		dd.default_tz = None
+
 	def testVariousTimes(self):
 		"""Test detection of various common date/time formats f2b should understand
 		"""