mylar/lib/apscheduler/triggers/cron/expressions.py

196 lines
6.4 KiB
Python

"""This module contains the expressions applicable for CronTrigger's fields."""
from calendar import monthrange
import re
from apscheduler.util import asint
__all__ = ('AllExpression', 'RangeExpression', 'WeekdayRangeExpression',
'WeekdayPositionExpression', 'LastDayOfMonthExpression')
WEEKDAYS = ['mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun']
class AllExpression(object):
value_re = re.compile(r'\*(?:/(?P<step>\d+))?$')
def __init__(self, step=None):
self.step = asint(step)
if self.step == 0:
raise ValueError('Increment must be higher than 0')
def get_next_value(self, date, field):
start = field.get_value(date)
minval = field.get_min(date)
maxval = field.get_max(date)
start = max(start, minval)
if not self.step:
next = start
else:
distance_to_next = (self.step - (start - minval)) % self.step
next = start + distance_to_next
if next <= maxval:
return next
def __eq__(self, other):
return isinstance(other, self.__class__) and self.step == other.step
def __str__(self):
if self.step:
return '*/%d' % self.step
return '*'
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, self.step)
class RangeExpression(AllExpression):
value_re = re.compile(
r'(?P<first>\d+)(?:-(?P<last>\d+))?(?:/(?P<step>\d+))?$')
def __init__(self, first, last=None, step=None):
AllExpression.__init__(self, step)
first = asint(first)
last = asint(last)
if last is None and step is None:
last = first
if last is not None and first > last:
raise ValueError('The minimum value in a range must not be higher than the maximum')
self.first = first
self.last = last
def get_next_value(self, date, field):
startval = field.get_value(date)
minval = field.get_min(date)
maxval = field.get_max(date)
# Apply range limits
minval = max(minval, self.first)
maxval = min(maxval, self.last) if self.last is not None else maxval
nextval = max(minval, startval)
# Apply the step if defined
if self.step:
distance_to_next = (self.step - (nextval - minval)) % self.step
nextval += distance_to_next
return nextval if nextval <= maxval else None
def __eq__(self, other):
return (isinstance(other, self.__class__) and self.first == other.first and
self.last == other.last)
def __str__(self):
if self.last != self.first and self.last is not None:
range = '%d-%d' % (self.first, self.last)
else:
range = str(self.first)
if self.step:
return '%s/%d' % (range, self.step)
return range
def __repr__(self):
args = [str(self.first)]
if self.last != self.first and self.last is not None or self.step:
args.append(str(self.last))
if self.step:
args.append(str(self.step))
return "%s(%s)" % (self.__class__.__name__, ', '.join(args))
class WeekdayRangeExpression(RangeExpression):
value_re = re.compile(r'(?P<first>[a-z]+)(?:-(?P<last>[a-z]+))?', re.IGNORECASE)
def __init__(self, first, last=None):
try:
first_num = WEEKDAYS.index(first.lower())
except ValueError:
raise ValueError('Invalid weekday name "%s"' % first)
if last:
try:
last_num = WEEKDAYS.index(last.lower())
except ValueError:
raise ValueError('Invalid weekday name "%s"' % last)
else:
last_num = None
RangeExpression.__init__(self, first_num, last_num)
def __str__(self):
if self.last != self.first and self.last is not None:
return '%s-%s' % (WEEKDAYS[self.first], WEEKDAYS[self.last])
return WEEKDAYS[self.first]
def __repr__(self):
args = ["'%s'" % WEEKDAYS[self.first]]
if self.last != self.first and self.last is not None:
args.append("'%s'" % WEEKDAYS[self.last])
return "%s(%s)" % (self.__class__.__name__, ', '.join(args))
class WeekdayPositionExpression(AllExpression):
options = ['1st', '2nd', '3rd', '4th', '5th', 'last']
value_re = re.compile(r'(?P<option_name>%s) +(?P<weekday_name>(?:\d+|\w+))' %
'|'.join(options), re.IGNORECASE)
def __init__(self, option_name, weekday_name):
try:
self.option_num = self.options.index(option_name.lower())
except ValueError:
raise ValueError('Invalid weekday position "%s"' % option_name)
try:
self.weekday = WEEKDAYS.index(weekday_name.lower())
except ValueError:
raise ValueError('Invalid weekday name "%s"' % weekday_name)
def get_next_value(self, date, field):
# Figure out the weekday of the month's first day and the number of days in that month
first_day_wday, last_day = monthrange(date.year, date.month)
# Calculate which day of the month is the first of the target weekdays
first_hit_day = self.weekday - first_day_wday + 1
if first_hit_day <= 0:
first_hit_day += 7
# Calculate what day of the month the target weekday would be
if self.option_num < 5:
target_day = first_hit_day + self.option_num * 7
else:
target_day = first_hit_day + ((last_day - first_hit_day) // 7) * 7
if target_day <= last_day and target_day >= date.day:
return target_day
def __eq__(self, other):
return (super(WeekdayPositionExpression, self).__eq__(other) and
self.option_num == other.option_num and self.weekday == other.weekday)
def __str__(self):
return '%s %s' % (self.options[self.option_num], WEEKDAYS[self.weekday])
def __repr__(self):
return "%s('%s', '%s')" % (self.__class__.__name__, self.options[self.option_num],
WEEKDAYS[self.weekday])
class LastDayOfMonthExpression(AllExpression):
value_re = re.compile(r'last', re.IGNORECASE)
def __init__(self):
pass
def get_next_value(self, date, field):
return monthrange(date.year, date.month)[1]
def __str__(self):
return 'last'
def __repr__(self):
return "%s()" % self.__class__.__name__