panikweb/utils.py

   1 from datetime import datetime, timedelta
   2
   3 import sorl.thumbnail.base
   4 from sorl.thumbnail import default
   5 from sorl.thumbnail.images import ImageFile
   6 from sorl.thumbnail.parsers import parse_geometry
   7
   8
   9 def tofirstdayinisoweek(year, week):
  10     # from http://stackoverflow.com/questions/5882405/get-date-from-iso-week-number-in-python
  11     ret = datetime.strptime('%04d-%02d-1' % (year, week), '%Y-%W-%w')
  12     if datetime(year, 1, 4).isoweekday() > 4:
  13         ret -= timedelta(days=7)
  14     return ret
  15
  16
  17 class ThumbnailBackend(sorl.thumbnail.base.ThumbnailBackend):
  18     def _create_alternative_resolutions(self, source_image, geometry_string, options, name):
  19         super()._create_alternative_resolutions(source_image, geometry_string, options, name)
  20         # create .webp alternative, to be served to appropriate browsers
  21         ratio = default.engine.get_image_ratio(source_image, options)
  22         geometry = parse_geometry(geometry_string, ratio)
  23         options = options.copy()
  24         options['format'] = 'WEBP'
  25         image = default.engine.create(source_image, geometry, options)
  26         thumbnail_name = '%(file_name)s.webp' % {'file_name': name}
  27         thumbnail = ImageFile(thumbnail_name, default.storage)
  28         default.engine.write(image, options, thumbnail)
  29         size = default.engine.get_image_size(image)
  30         thumbnail.set_size(size)