1 #
2 # Copyright (c) 2001 Bizar Software Pty Ltd (http://www.bizarsoftware.com.au/)
3 # This module is free software, and you may redistribute it and/or modify
4 # under the same terms as Python, so long as this copyright message and
5 # disclaimer are retained in their original form.
6 #
7 # IN NO EVENT SHALL BIZAR SOFTWARE PTY LTD BE LIABLE TO ANY PARTY FOR
8 # DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING
9 # OUT OF THE USE OF THIS CODE, EVEN IF THE AUTHOR HAS BEEN ADVISED OF THE
10 # POSSIBILITY OF SUCH DAMAGE.
11 #
12 # BIZAR SOFTWARE PTY LTD SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
13 # BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
14 # FOR A PARTICULAR PURPOSE. THE CODE PROVIDED HEREUNDER IS ON AN "AS IS"
15 # BASIS, AND THERE IS NO OBLIGATION WHATSOEVER TO PROVIDE MAINTENANCE,
16 # SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
17 #
18 # $Id: date.py,v 1.20 2002-02-21 23:34:51 richard Exp $
20 __doc__ = """
21 Date, time and time interval handling.
22 """
24 import time, re, calendar
25 from i18n import _
27 class Date:
28 '''
29 As strings, date-and-time stamps are specified with the date in
30 international standard format (yyyy-mm-dd) joined to the time
31 (hh:mm:ss) by a period ("."). Dates in this form can be easily compared
32 and are fairly readable when printed. An example of a valid stamp is
33 "2000-06-24.13:03:59". We'll call this the "full date format". When
34 Timestamp objects are printed as strings, they appear in the full date
35 format with the time always given in GMT. The full date format is
36 always exactly 19 characters long.
38 For user input, some partial forms are also permitted: the whole time
39 or just the seconds may be omitted; and the whole date may be omitted
40 or just the year may be omitted. If the time is given, the time is
41 interpreted in the user's local time zone. The Date constructor takes
42 care of these conversions. In the following examples, suppose that yyyy
43 is the current year, mm is the current month, and dd is the current day
44 of the month; and suppose that the user is on Eastern Standard Time.
46 "2000-04-17" means <Date 2000-04-17.00:00:00>
47 "01-25" means <Date yyyy-01-25.00:00:00>
48 "2000-04-17.03:45" means <Date 2000-04-17.08:45:00>
49 "08-13.22:13" means <Date yyyy-08-14.03:13:00>
50 "11-07.09:32:43" means <Date yyyy-11-07.14:32:43>
51 "14:25" means <Date yyyy-mm-dd.19:25:00>
52 "8:47:11" means <Date yyyy-mm-dd.13:47:11>
53 "." means "right now"
55 The Date class should understand simple date expressions of the form
56 stamp + interval and stamp - interval. When adding or subtracting
57 intervals involving months or years, the components are handled
58 separately. For example, when evaluating "2000-06-25 + 1m 10d", we
59 first add one month to get 2000-07-25, then add 10 days to get
60 2000-08-04 (rather than trying to decide whether 1m 10d means 38 or 40
61 or 41 days).
63 Example usage:
64 >>> Date(".")
65 <Date 2000-06-26.00:34:02>
66 >>> _.local(-5)
67 "2000-06-25.19:34:02"
68 >>> Date(". + 2d")
69 <Date 2000-06-28.00:34:02>
70 >>> Date("1997-04-17", -5)
71 <Date 1997-04-17.00:00:00>
72 >>> Date("01-25", -5)
73 <Date 2000-01-25.00:00:00>
74 >>> Date("08-13.22:13", -5)
75 <Date 2000-08-14.03:13:00>
76 >>> Date("14:25", -5)
77 <Date 2000-06-25.19:25:00>
78 '''
79 def __init__(self, spec='.', offset=0):
80 """Construct a date given a specification and a time zone offset.
82 'spec' is a full date or a partial form, with an optional
83 added or subtracted interval. Or a date 9-tuple.
84 'offset' is the local time zone offset from GMT in hours.
85 """
86 if type(spec) == type(''):
87 self.set(spec, offset=offset)
88 else:
89 y,m,d,H,M,S,x,x,x = spec
90 ts = calendar.timegm((y,m,d,H+offset,M,S,0,0,0))
91 self.year, self.month, self.day, self.hour, self.minute, \
92 self.second, x, x, x = time.gmtime(ts)
94 def applyInterval(self, interval):
95 ''' Apply the interval to this date
96 '''
97 t = (self.year + interval.year,
98 self.month + interval.month,
99 self.day + interval.day,
100 self.hour + interval.hour,
101 self.minute + interval.minute,
102 self.second + interval.second, 0, 0, 0)
103 self.year, self.month, self.day, self.hour, self.minute, \
104 self.second, x, x, x = time.gmtime(calendar.timegm(t))
106 def __add__(self, other):
107 """Add an interval to this date to produce another date.
108 """
109 # do the basic calc
110 sign = other.sign
111 year = self.year + sign * other.year
112 month = self.month + sign * other.month
113 day = self.day + sign * other.day
114 hour = self.hour + sign * other.hour
115 minute = self.minute + sign * other.minute
116 second = self.second + sign * other.second
118 # now cope with under- and over-flow
119 # first do the time
120 while (second < 0 or second > 59 or minute < 0 or minute > 59 or
121 hour < 0 or hour > 59):
122 if second < 0: minute -= 1; second += 60
123 elif second > 59: minute += 1; second -= 60
124 if minute < 0: hour -= 1; minute += 60
125 elif minute > 59: hour += 1; minute -= 60
126 if hour < 0: day -= 1; hour += 24
127 elif hour > 59: day += 1; hour -= 24
129 # fix up the month so we're within range
130 while month < 1 or month > 12:
131 if month < 1: year -= 1; month += 12
132 if month > 12: year += 1; month -= 12
134 # now do the days, now that we know what month we're in
135 mdays = calendar.mdays
136 if month == 2 and calendar.isleap(year): month_days = 29
137 else: month_days = mdays[month]
138 while month < 1 or month > 12 or day < 0 or day > month_days:
139 # now to day under/over
140 if day < 0: month -= 1; day += month_days
141 elif day > month_days: month += 1; day -= month_days
143 # possibly fix up the month so we're within range
144 while month < 1 or month > 12:
145 if month < 1: year -= 1; month += 12
146 if month > 12: year += 1; month -= 12
148 # re-figure the number of days for this month
149 if month == 2 and calendar.isleap(year): month_days = 29
150 else: month_days = mdays[month]
152 return Date((year, month, day, hour, minute, second, 0, 0, 0))
154 # XXX deviates from spec to allow subtraction of dates as well
155 def __sub__(self, other):
156 """ Subtract:
157 1. an interval from this date to produce another date.
158 2. a date from this date to produce an interval.
159 """
160 if isinstance(other, Interval):
161 other = Interval(other.get_tuple(), sign=-other.sign)
162 return self.__add__(other)
164 assert isinstance(other, Date), 'May only subtract Dates or Intervals'
166 # TODO this code will fall over laughing if the dates cross
167 # leap years, phases of the moon, ....
168 a = calendar.timegm((self.year, self.month, self.day, self.hour,
169 self.minute, self.second, 0, 0, 0))
170 b = calendar.timegm((other.year, other.month, other.day,
171 other.hour, other.minute, other.second, 0, 0, 0))
172 diff = a - b
173 if diff < 0:
174 sign = 1
175 diff = -diff
176 else:
177 sign = -1
178 S = diff%60
179 M = (diff/60)%60
180 H = (diff/(60*60))%60
181 if H>1: S = 0
182 d = (diff/(24*60*60))%30
183 if d>1: H = S = M = 0
184 m = (diff/(30*24*60*60))%12
185 if m>1: H = S = M = 0
186 y = (diff/(365*24*60*60))
187 if y>1: d = H = S = M = 0
188 return Interval((y, m, d, H, M, S), sign=sign)
190 def __cmp__(self, other):
191 """Compare this date to another date."""
192 if other is None:
193 return 1
194 for attr in ('year', 'month', 'day', 'hour', 'minute', 'second'):
195 r = cmp(getattr(self, attr), getattr(other, attr))
196 if r: return r
197 return 0
199 def __str__(self):
200 """Return this date as a string in the yyyy-mm-dd.hh:mm:ss format."""
201 return '%4d-%02d-%02d.%02d:%02d:%02d'%(self.year, self.month, self.day,
202 self.hour, self.minute, self.second)
204 def pretty(self):
205 ''' print up the date date using a pretty format...
206 '''
207 str = time.strftime('%d %B %Y', (self.year, self.month,
208 self.day, self.hour, self.minute, self.second, 0, 0, 0))
209 if str[0] == '0': return ' ' + str[1:]
210 return str
212 def set(self, spec, offset=0, date_re=re.compile(r'''
213 (((?P<y>\d\d\d\d)-)?((?P<m>\d\d?)-(?P<d>\d\d?))?)? # yyyy-mm-dd
214 (?P<n>\.)? # .
215 (((?P<H>\d?\d):(?P<M>\d\d))?(:(?P<S>\d\d))?)? # hh:mm:ss
216 (?P<o>.+)? # offset
217 ''', re.VERBOSE)):
218 ''' set the date to the value in spec
219 '''
220 m = date_re.match(spec)
221 if not m:
222 raise ValueError, _('Not a date spec: [[yyyy-]mm-dd].[[h]h:mm[:ss]]'
223 '[offset]')
224 info = m.groupdict()
226 # get the current date/time using the offset
227 y,m,d,H,M,S,x,x,x = time.gmtime(time.time())
229 # override year, month, day parts
230 if info['m'] is not None and info['d'] is not None:
231 m = int(info['m'])
232 d = int(info['d'])
233 if info['y'] is not None: y = int(info['y'])
234 H = M = S = 0
236 # override hour, minute, second parts
237 if info['H'] is not None and info['M'] is not None:
238 H = int(info['H']) - offset
239 M = int(info['M'])
240 S = 0
241 if info['S'] is not None: S = int(info['S'])
243 # now handle the adjustment of hour
244 ts = calendar.timegm((y,m,d,H,M,S,0,0,0))
245 self.year, self.month, self.day, self.hour, self.minute, \
246 self.second, x, x, x = time.gmtime(ts)
248 if info['o']:
249 self.applyInterval(Interval(info['o']))
251 def __repr__(self):
252 return '<Date %s>'%self.__str__()
254 def local(self, offset):
255 """Return this date as yyyy-mm-dd.hh:mm:ss in a local time zone."""
256 t = (self.year, self.month, self.day, self.hour + offset, self.minute,
257 self.second, 0, 0, 0)
258 self.year, self.month, self.day, self.hour, self.minute, \
259 self.second, x, x, x = time.gmtime(calendar.timegm(t))
261 def get_tuple(self):
262 return (self.year, self.month, self.day, self.hour, self.minute,
263 self.second, 0, 0, 0)
265 class Interval:
266 '''
267 Date intervals are specified using the suffixes "y", "m", and "d". The
268 suffix "w" (for "week") means 7 days. Time intervals are specified in
269 hh:mm:ss format (the seconds may be omitted, but the hours and minutes
270 may not).
272 "3y" means three years
273 "2y 1m" means two years and one month
274 "1m 25d" means one month and 25 days
275 "2w 3d" means two weeks and three days
276 "1d 2:50" means one day, two hours, and 50 minutes
277 "14:00" means 14 hours
278 "0:04:33" means four minutes and 33 seconds
280 Example usage:
281 >>> Interval(" 3w 1 d 2:00")
282 <Interval 22d 2:00>
283 >>> Date(". + 2d") + Interval("- 3w")
284 <Date 2000-06-07.00:34:02>
286 Intervals are added/subtracted in order of:
287 seconds, minutes, hours, years, months, days
289 Calculations involving monts (eg '+2m') have no effect on days - only
290 days (or over/underflow from hours/mins/secs) will do that, and
291 days-per-month and leap years are accounted for. Leap seconds are not.
293 TODO: more examples, showing the order of addition operation
294 '''
295 def __init__(self, spec, sign=1):
296 """Construct an interval given a specification."""
297 if type(spec) == type(''):
298 self.set(spec)
299 else:
300 self.sign = sign
301 self.year, self.month, self.day, self.hour, self.minute, \
302 self.second = spec
304 def __cmp__(self, other):
305 """Compare this interval to another interval."""
306 if other is None:
307 return 1
308 for attr in ('year', 'month', 'day', 'hour', 'minute', 'second'):
309 r = cmp(getattr(self, attr), getattr(other, attr))
310 if r: return r
311 return 0
313 def __str__(self):
314 """Return this interval as a string."""
315 sign = {1:'+', -1:'-'}[self.sign]
316 l = [sign]
317 if self.year: l.append('%sy'%self.year)
318 if self.month: l.append('%sm'%self.month)
319 if self.day: l.append('%sd'%self.day)
320 if self.second:
321 l.append('%d:%02d:%02d'%(self.hour, self.minute, self.second))
322 elif self.hour or self.minute:
323 l.append('%d:%02d'%(self.hour, self.minute))
324 return ' '.join(l)
326 def set(self, spec, interval_re = re.compile('''
327 \s*
328 (?P<s>[-+])? # + or -
329 \s*
330 ((?P<y>\d+\s*)y)? # year
331 \s*
332 ((?P<m>\d+\s*)m)? # month
333 \s*
334 ((?P<w>\d+\s*)w)? # week
335 \s*
336 ((?P<d>\d+\s*)d)? # day
337 \s*
338 (((?P<H>\d+):(?P<M>\d+))?(:(?P<S>\d+))?)? # time
339 \s*
340 ''', re.VERBOSE)):
341 ''' set the date to the value in spec
342 '''
343 self.year = self.month = self.week = self.day = self.hour = \
344 self.minute = self.second = 0
345 self.sign = 1
346 m = interval_re.match(spec)
347 if not m:
348 raise ValueError, _('Not an interval spec: [+-] [#y] [#m] [#w] '
349 '[#d] [[[H]H:MM]:SS]')
351 info = m.groupdict()
352 for group, attr in {'y':'year', 'm':'month', 'w':'week', 'd':'day',
353 'H':'hour', 'M':'minute', 'S':'second'}.items():
354 if info[group] is not None:
355 setattr(self, attr, int(info[group]))
357 if self.week:
358 self.day = self.day + self.week*7
360 if info['s'] is not None:
361 self.sign = {'+':1, '-':-1}[info['s']]
363 def __repr__(self):
364 return '<Interval %s>'%self.__str__()
366 def pretty(self):
367 ''' print up the date date using one of these nice formats..
368 '''
369 if self.year or self.month > 2:
370 return None
371 elif self.month or self.day > 13:
372 days = (self.month * 30) + self.day
373 if days > 28:
374 if int(days/30) > 1:
375 s = _('%(number)s months')%{'number': int(days/30)}
376 else:
377 s = _('1 month')
378 else:
379 s = _('%(number)s weeks')%{'number': int(days/7)}
380 elif self.day > 7:
381 s = _('1 week')
382 elif self.day > 1:
383 s = _('%(number)s days')%{'number': self.day}
384 elif self.day == 1 or self.hour > 12:
385 if self.sign > 0:
386 return _('tomorrow')
387 else:
388 return _('yesterday')
389 elif self.hour > 1:
390 s = _('%(number)s hours')%{'number': self.hour}
391 elif self.hour == 1:
392 if self.minute < 15:
393 s = _('an hour')
394 elif self.minute/15 == 2:
395 s = _('1 1/2 hours')
396 else:
397 s = _('1 %(number)s/4 hours')%{'number': self.minute/15}
398 elif self.minute < 1:
399 if self.sign > 0:
400 return _('in a moment')
401 else:
402 return _('just now')
403 elif self.minute == 1:
404 s = _('1 minute')
405 elif self.minute < 15:
406 s = _('%(number)s minutes')%{'number': self.minute}
407 elif int(self.minute/15) == 2:
408 s = _('1/2 an hour')
409 else:
410 s = _('%(number)s/4 hour')%{'number': int(self.minute/15)}
411 return s
413 def get_tuple(self):
414 return (self.year, self.month, self.day, self.hour, self.minute,
415 self.second)
418 def test():
419 intervals = (" 3w 1 d 2:00", " + 2d", "3w")
420 for interval in intervals:
421 print '>>> Interval("%s")'%interval
422 print `Interval(interval)`
424 dates = (".", "2000-06-25.19:34:02", ". + 2d", "1997-04-17", "01-25",
425 "08-13.22:13", "14:25")
426 for date in dates:
427 print '>>> Date("%s")'%date
428 print `Date(date)`
430 sums = ((". + 2d", "3w"), (".", " 3w 1 d 2:00"))
431 for date, interval in sums:
432 print '>>> Date("%s") + Interval("%s")'%(date, interval)
433 print `Date(date) + Interval(interval)`
435 if __name__ == '__main__':
436 test()
438 #
439 # $Log: not supported by cvs2svn $
440 # Revision 1.19 2002/02/21 23:11:45 richard
441 # . fixed some problems in date calculations (calendar.py doesn't handle over-
442 # and under-flow). Also, hour/minute/second intervals may now be more than
443 # 99 each.
444 #
445 # Revision 1.18 2002/01/23 20:00:50 jhermann
446 # %e is a UNIXism and not documented for Python
447 #
448 # Revision 1.17 2002/01/16 07:02:57 richard
449 # . lots of date/interval related changes:
450 # - more relaxed date format for input
451 #
452 # Revision 1.16 2002/01/08 11:56:24 richard
453 # missed an import _
454 #
455 # Revision 1.15 2002/01/05 02:27:00 richard
456 # I18N'ification
457 #
458 # Revision 1.14 2001/11/22 15:46:42 jhermann
459 # Added module docstrings to all modules.
460 #
461 # Revision 1.13 2001/09/18 22:58:37 richard
462 #
463 # Added some more help to roundu-admin
464 #
465 # Revision 1.12 2001/08/17 03:08:11 richard
466 # fixed prettification of intervals of 1 week
467 #
468 # Revision 1.11 2001/08/15 23:43:18 richard
469 # Fixed some isFooTypes that I missed.
470 # Refactored some code in the CGI code.
471 #
472 # Revision 1.10 2001/08/07 00:24:42 richard
473 # stupid typo
474 #
475 # Revision 1.9 2001/08/07 00:15:51 richard
476 # Added the copyright/license notice to (nearly) all files at request of
477 # Bizar Software.
478 #
479 # Revision 1.8 2001/08/05 07:46:12 richard
480 # Changed date.Date to use regular string formatting instead of strftime -
481 # win32 seems to have problems with %T and no hour... or something...
482 #
483 # Revision 1.7 2001/08/02 00:27:04 richard
484 # Extended the range of intervals that are pretty-printed before actual dates
485 # are displayed.
486 #
487 # Revision 1.6 2001/07/31 09:54:18 richard
488 # Fixed the 2.1-specific gmtime() (no arg) call in roundup.date. (Paul Wright)
489 #
490 # Revision 1.5 2001/07/29 07:01:39 richard
491 # Added vim command to all source so that we don't get no steenkin' tabs :)
492 #
493 # Revision 1.4 2001/07/25 04:09:34 richard
494 # Fixed offset handling (shoulda read the spec a little better)
495 #
496 # Revision 1.3 2001/07/23 07:56:05 richard
497 # Storing only marshallable data in the db - no nasty pickled class references.
498 #
499 # Revision 1.2 2001/07/22 12:09:32 richard
500 # Final commit of Grande Splite
501 #
502 # Revision 1.1 2001/07/22 11:58:35 richard
503 # More Grande Splite
504 #
505 #
506 # vim: set filetype=python ts=4 sw=4 et si