django/utils/timesince.py

   1 import datetime
   2 import time
   3
   4 from django.utils.tzinfo import LocalTimezone
   5 from django.utils.translation import ungettext, ugettext
   6
   7 def timesince(d, now=None):
   8     """
   9     Takes two datetime objects and returns the time between d and now
  10     as a nicely formatted string, e.g. "10 minutes".  If d occurs after now,
  11     then "0 minutes" is returned.
  12
  13     Units used are years, months, weeks, days, hours, and minutes.
  14     Seconds and microseconds are ignored.  Up to two adjacent units will be
  15     displayed.  For example, "2 weeks, 3 days" and "1 year, 3 months" are
  16     possible outputs, but "2 weeks, 3 hours" and "1 year, 5 days" are not.
  17
  18     Adapted from http://blog.natbat.co.uk/archive/2003/Jun/14/time_since
  19     """
  20     chunks = (
  21       (60 * 60 * 24 * 365, lambda n: ungettext('year', 'years', n)),
  22       (60 * 60 * 24 * 30, lambda n: ungettext('month', 'months', n)),
  23       (60 * 60 * 24 * 7, lambda n : ungettext('week', 'weeks', n)),
  24       (60 * 60 * 24, lambda n : ungettext('day', 'days', n)),
  25       (60 * 60, lambda n: ungettext('hour', 'hours', n)),
  26       (60, lambda n: ungettext('minute', 'minutes', n))
  27     )
  28     # Convert datetime.date to datetime.datetime for comparison
  29     if d.__class__ is not datetime.datetime:
  30         d = datetime.datetime(d.year, d.month, d.day)
  31
  32     if not now:
  33         if d.tzinfo:
  34             now = datetime.datetime.now(LocalTimezone(d))
  35         else:
  36             now = datetime.datetime.now()
  37
  38     # ignore microsecond part of 'd' since we removed it from 'now'
  39     delta = now - (d - datetime.timedelta(0, 0, d.microsecond))
  40     since = delta.days * 24 * 60 * 60 + delta.seconds
  41     if since <= 0:
  42         # d is in the future compared to now, stop processing.
  43         return u'0 ' + ugettext('minutes')
  44     for i, (seconds, name) in enumerate(chunks):
  45         count = since // seconds
  46         if count != 0:
  47             break
  48     s = ugettext('%(number)d %(type)s') % {'number': count, 'type': name(count)}
  49     if i + 1 < len(chunks):
  50         # Now get the second item
  51         seconds2, name2 = chunks[i + 1]
  52         count2 = (since - (seconds * count)) // seconds2
  53         if count2 != 0:
  54             s += ugettext(', %(number)d %(type)s') % {'number': count2, 'type': name2(count2)}
  55     return s
  56
  57 def timeuntil(d, now=None):
  58     """
  59     Like timesince, but returns a string measuring the time until
  60     the given time.
  61     """
  62     if not now:
  63         if getattr(d, 'tzinfo', None):
  64             now = datetime.datetime.now(LocalTimezone(d))
  65         else:
  66             now = datetime.datetime.now()
  67     return timesince(now, d)