Package logilab :: Package common :: Module date
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Source Code for Module logilab.common.date

  1  # copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved. 
  2  # contact http://www.logilab.fr/ -- mailto:contact@logilab.fr 
  3  # 
  4  # This file is part of logilab-common. 
  5  # 
  6  # logilab-common is free software: you can redistribute it and/or modify it under 
  7  # the terms of the GNU Lesser General Public License as published by the Free 
  8  # Software Foundation, either version 2.1 of the License, or (at your option) any 
  9  # later version. 
 10  # 
 11  # logilab-common is distributed in the hope that it will be useful, but WITHOUT 
 12  # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 
 13  # FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more 
 14  # details. 
 15  # 
 16  # You should have received a copy of the GNU Lesser General Public License along 
 17  # with logilab-common.  If not, see <http://www.gnu.org/licenses/>. 
 18  """Date manipulation helper functions.""" 
 19  from __future__ import division 
 20   
 21  __docformat__ = "restructuredtext en" 
 22   
 23  import math 
 24  import re 
 25  import sys 
 26  from locale import getlocale, LC_TIME 
 27  from datetime import date, time, datetime, timedelta 
 28  from time import strptime as time_strptime 
 29  from calendar import monthrange, timegm 
 30   
 31  from six.moves import range 
 32   
 33  try: 
 34      from mx.DateTime import RelativeDateTime, Date, DateTimeType 
 35  except ImportError: 
 36      endOfMonth = None 
 37      DateTimeType = datetime 
 38  else: 
 39      endOfMonth = RelativeDateTime(months=1, day=-1) 
 40   
 41  # NOTE: should we implement a compatibility layer between date representations 
 42  #       as we have in lgc.db ? 
 43   
 44  FRENCH_FIXED_HOLIDAYS = { 
 45      'jour_an': '%s-01-01', 
 46      'fete_travail': '%s-05-01', 
 47      'armistice1945': '%s-05-08', 
 48      'fete_nat': '%s-07-14', 
 49      'assomption': '%s-08-15', 
 50      'toussaint': '%s-11-01', 
 51      'armistice1918': '%s-11-11', 
 52      'noel': '%s-12-25', 
 53      } 
 54   
 55  FRENCH_MOBILE_HOLIDAYS = { 
 56      'paques2004': '2004-04-12', 
 57      'ascension2004': '2004-05-20', 
 58      'pentecote2004': '2004-05-31', 
 59   
 60      'paques2005': '2005-03-28', 
 61      'ascension2005': '2005-05-05', 
 62      'pentecote2005': '2005-05-16', 
 63   
 64      'paques2006': '2006-04-17', 
 65      'ascension2006': '2006-05-25', 
 66      'pentecote2006': '2006-06-05', 
 67   
 68      'paques2007': '2007-04-09', 
 69      'ascension2007': '2007-05-17', 
 70      'pentecote2007': '2007-05-28', 
 71   
 72      'paques2008': '2008-03-24', 
 73      'ascension2008': '2008-05-01', 
 74      'pentecote2008': '2008-05-12', 
 75   
 76      'paques2009': '2009-04-13', 
 77      'ascension2009': '2009-05-21', 
 78      'pentecote2009': '2009-06-01', 
 79   
 80      'paques2010': '2010-04-05', 
 81      'ascension2010': '2010-05-13', 
 82      'pentecote2010': '2010-05-24', 
 83   
 84      'paques2011': '2011-04-25', 
 85      'ascension2011': '2011-06-02', 
 86      'pentecote2011': '2011-06-13', 
 87   
 88      'paques2012': '2012-04-09', 
 89      'ascension2012': '2012-05-17', 
 90      'pentecote2012': '2012-05-28', 
 91      } 
 92   
 93  # XXX this implementation cries for multimethod dispatching 
 94   
95 -def get_step(dateobj, nbdays=1):
96 # assume date is either a python datetime or a mx.DateTime object 97 if isinstance(dateobj, date): 98 return ONEDAY * nbdays 99 return nbdays # mx.DateTime is ok with integers
100
101 -def datefactory(year, month, day, sampledate):
102 # assume date is either a python datetime or a mx.DateTime object 103 if isinstance(sampledate, datetime): 104 return datetime(year, month, day) 105 if isinstance(sampledate, date): 106 return date(year, month, day) 107 return Date(year, month, day)
108
109 -def weekday(dateobj):
110 # assume date is either a python datetime or a mx.DateTime object 111 if isinstance(dateobj, date): 112 return dateobj.weekday() 113 return dateobj.day_of_week
114
115 -def str2date(datestr, sampledate):
116 # NOTE: datetime.strptime is not an option until we drop py2.4 compat 117 year, month, day = [int(chunk) for chunk in datestr.split('-')] 118 return datefactory(year, month, day, sampledate)
119
120 -def days_between(start, end):
121 if isinstance(start, date): 122 delta = end - start 123 # datetime.timedelta.days is always an integer (floored) 124 if delta.seconds: 125 return delta.days + 1 126 return delta.days 127 else: 128 return int(math.ceil((end - start).days))
129
130 -def get_national_holidays(begin, end):
131 """return french national days off between begin and end""" 132 begin = datefactory(begin.year, begin.month, begin.day, begin) 133 end = datefactory(end.year, end.month, end.day, end) 134 holidays = [str2date(datestr, begin) 135 for datestr in FRENCH_MOBILE_HOLIDAYS.values()] 136 for year in range(begin.year, end.year+1): 137 for datestr in FRENCH_FIXED_HOLIDAYS.values(): 138 date = str2date(datestr % year, begin) 139 if date not in holidays: 140 holidays.append(date) 141 return [day for day in holidays if begin <= day < end]
142
143 -def add_days_worked(start, days):
144 """adds date but try to only take days worked into account""" 145 step = get_step(start) 146 weeks, plus = divmod(days, 5) 147 end = start + ((weeks * 7) + plus) * step 148 if weekday(end) >= 5: # saturday or sunday 149 end += (2 * step) 150 end += len([x for x in get_national_holidays(start, end + step) 151 if weekday(x) < 5]) * step 152 if weekday(end) >= 5: # saturday or sunday 153 end += (2 * step) 154 return end
155
156 -def nb_open_days(start, end):
157 assert start <= end 158 step = get_step(start) 159 days = days_between(start, end) 160 weeks, plus = divmod(days, 7) 161 if weekday(start) > weekday(end): 162 plus -= 2 163 elif weekday(end) == 6: 164 plus -= 1 165 open_days = weeks * 5 + plus 166 nb_week_holidays = len([x for x in get_national_holidays(start, end+step) 167 if weekday(x) < 5 and x < end]) 168 open_days -= nb_week_holidays 169 if open_days < 0: 170 return 0 171 return open_days
172
173 -def date_range(begin, end, incday=None, incmonth=None):
174 """yields each date between begin and end 175 176 :param begin: the start date 177 :param end: the end date 178 :param incr: the step to use to iterate over dates. Default is 179 one day. 180 :param include: None (means no exclusion) or a function taking a 181 date as parameter, and returning True if the date 182 should be included. 183 184 When using mx datetime, you should *NOT* use incmonth argument, use instead 185 oneDay, oneHour, oneMinute, oneSecond, oneWeek or endOfMonth (to enumerate 186 months) as `incday` argument 187 """ 188 assert not (incday and incmonth) 189 begin = todate(begin) 190 end = todate(end) 191 if incmonth: 192 while begin < end: 193 yield begin 194 begin = next_month(begin, incmonth) 195 else: 196 incr = get_step(begin, incday or 1) 197 while begin < end: 198 yield begin 199 begin += incr
200 201 # makes py datetime usable ##################################################### 202 203 ONEDAY = timedelta(days=1) 204 ONEWEEK = timedelta(days=7) 205 206 try: 207 strptime = datetime.strptime 208 except AttributeError: # py < 2.5 209 from time import strptime as time_strptime
210 - def strptime(value, format):
211 return datetime(*time_strptime(value, format)[:6])
212
213 -def strptime_time(value, format='%H:%M'):
214 return time(*time_strptime(value, format)[3:6])
215
216 -def todate(somedate):
217 """return a date from a date (leaving unchanged) or a datetime""" 218 if isinstance(somedate, datetime): 219 return date(somedate.year, somedate.month, somedate.day) 220 assert isinstance(somedate, (date, DateTimeType)), repr(somedate) 221 return somedate
222
223 -def totime(somedate):
224 """return a time from a time (leaving unchanged), date or datetime""" 225 # XXX mx compat 226 if not isinstance(somedate, time): 227 return time(somedate.hour, somedate.minute, somedate.second) 228 assert isinstance(somedate, (time)), repr(somedate) 229 return somedate
230
231 -def todatetime(somedate):
232 """return a date from a date (leaving unchanged) or a datetime""" 233 # take care, datetime is a subclass of date 234 if isinstance(somedate, datetime): 235 return somedate 236 assert isinstance(somedate, (date, DateTimeType)), repr(somedate) 237 return datetime(somedate.year, somedate.month, somedate.day)
238
239 -def datetime2ticks(somedate):
240 return timegm(somedate.timetuple()) * 1000 + int(somedate.microsecond / 1000)
241
242 -def ticks2datetime(ticks):
243 miliseconds, microseconds = divmod(ticks, 1000) 244 try: 245 return datetime.fromtimestamp(miliseconds) 246 except (ValueError, OverflowError): 247 epoch = datetime.fromtimestamp(0) 248 nb_days, seconds = divmod(int(miliseconds), 86400) 249 delta = timedelta(nb_days, seconds=seconds, microseconds=microseconds) 250 try: 251 return epoch + delta 252 except (ValueError, OverflowError): 253 raise
254
255 -def days_in_month(somedate):
256 return monthrange(somedate.year, somedate.month)[1]
257
258 -def days_in_year(somedate):
259 feb = date(somedate.year, 2, 1) 260 if days_in_month(feb) == 29: 261 return 366 262 else: 263 return 365
264
265 -def previous_month(somedate, nbmonth=1):
266 while nbmonth: 267 somedate = first_day(somedate) - ONEDAY 268 nbmonth -= 1 269 return somedate
270
271 -def next_month(somedate, nbmonth=1):
272 while nbmonth: 273 somedate = last_day(somedate) + ONEDAY 274 nbmonth -= 1 275 return somedate
276
277 -def first_day(somedate):
278 return date(somedate.year, somedate.month, 1)
279
280 -def last_day(somedate):
281 return date(somedate.year, somedate.month, days_in_month(somedate))
282
283 -def ustrftime(somedate, fmt='%Y-%m-%d'):
284 """like strftime, but returns a unicode string instead of an encoded 285 string which may be problematic with localized date. 286 """ 287 if sys.version_info >= (3, 3): 288 # datetime.date.strftime() supports dates since year 1 in Python >=3.3. 289 return somedate.strftime(fmt) 290 else: 291 try: 292 if sys.version_info < (3, 0): 293 encoding = getlocale(LC_TIME)[1] or 'ascii' 294 return unicode(somedate.strftime(str(fmt)), encoding) 295 else: 296 return somedate.strftime(fmt) 297 except ValueError: 298 if somedate.year >= 1900: 299 raise 300 # datetime is not happy with dates before 1900 301 # we try to work around this, assuming a simple 302 # format string 303 fields = {'Y': somedate.year, 304 'm': somedate.month, 305 'd': somedate.day, 306 } 307 if isinstance(somedate, datetime): 308 fields.update({'H': somedate.hour, 309 'M': somedate.minute, 310 'S': somedate.second}) 311 fmt = re.sub('%([YmdHMS])', r'%(\1)02d', fmt) 312 return unicode(fmt) % fields
313
314 -def utcdatetime(dt):
315 if dt.tzinfo is None: 316 return dt 317 return (dt.replace(tzinfo=None) - dt.utcoffset())
318
319 -def utctime(dt):
320 if dt.tzinfo is None: 321 return dt 322 return (dt + dt.utcoffset() + dt.dst()).replace(tzinfo=None)
323
324 -def datetime_to_seconds(date):
325 """return the number of seconds since the begining of the day for that date 326 """ 327 return date.second+60*date.minute + 3600*date.hour
328
329 -def timedelta_to_days(delta):
330 """return the time delta as a number of seconds""" 331 return delta.days + delta.seconds / (3600*24)
332
333 -def timedelta_to_seconds(delta):
334 """return the time delta as a fraction of days""" 335 return delta.days*(3600*24) + delta.seconds
336