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annotate gpp/potd/models.py @ 532:ff67946fd4b0

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For #242, move the updating of the POTD sequence into a new signals module. When photos are deleted from the admin changelist in bulk, the individual delete() functions on the photo objects is not called. However, the post_delete signal is called for each object.
author Brian Neal <bgneal@gmail.com>
date Sun, 25 Dec 2011 04:15:32 +0000
parents ae89ba801e8b
children 4021ea1045f7
rev   line source
gremmie@1 1 """
gremmie@1 2 Models for the Photo Of The Day (POTD) application.
bgneal@515 3
gremmie@1 4 """
gremmie@1 5 import os
gremmie@1 6 from PIL import ImageFile
gremmie@1 7 from PIL import Image
gremmie@1 8 try:
gremmie@1 9 from cStringIO import StringIO
gremmie@1 10 except:
gremmie@1 11 from StringIO import StringIO
gremmie@1 12
gremmie@1 13 from django.db import models
gremmie@1 14 from django.contrib.auth.models import User
gremmie@1 15 from django.core.files.base import ContentFile
gremmie@1 16
gremmie@1 17 POTD_THUMB_WIDTH = 120
gremmie@1 18
gremmie@1 19 def scale_image(image):
gremmie@1 20 (w, h) = image.size
gremmie@1 21 if w <= POTD_THUMB_WIDTH:
gremmie@1 22 return image
gremmie@1 23 scale_factor = float(POTD_THUMB_WIDTH) / w
gremmie@1 24 new_height = int(scale_factor * h)
gremmie@1 25 return image.resize((POTD_THUMB_WIDTH, new_height), Image.ANTIALIAS)
gremmie@1 26
gremmie@1 27
gremmie@1 28 class Photo(models.Model):
gremmie@1 29 """Model to represent a POTD"""
gremmie@1 30 photo = models.ImageField(upload_to='potd/%Y/%m/%d')
gremmie@1 31 thumb = models.ImageField(upload_to='potd/%Y/%m/%d/thumbs', blank=True, null=True)
gremmie@1 32 caption = models.CharField(max_length=128)
gremmie@1 33 description = models.TextField()
gremmie@1 34 user = models.ForeignKey(User)
gremmie@1 35 date_added = models.DateField(auto_now_add=True)
gremmie@1 36 potd_count = models.IntegerField(default=0)
gremmie@1 37
bgneal@14 38 class Meta:
bgneal@14 39 ordering = ('-date_added', '-caption')
bgneal@14 40
gremmie@1 41 def __unicode__(self):
gremmie@1 42 return u'%s (%s)' % (self.caption, self.pk)
gremmie@1 43
bgneal@14 44 @models.permalink
bgneal@14 45 def get_absolute_url(self):
bgneal@14 46 return ('potd-archive', [str(self.id)])
gremmie@1 47
bgneal@182 48 def save(self, *args, **kwargs):
bgneal@330 49 if not self.pk:
bgneal@330 50 self.generate_thumb()
gremmie@1 51
bgneal@330 52 super(Photo, self).save(*args, **kwargs)
bgneal@330 53
bgneal@330 54 def can_comment_on(self):
bgneal@330 55 return Current.objects.get_current_id() == self.id
bgneal@330 56
bgneal@330 57 def generate_thumb(self):
gremmie@1 58 if self.thumb:
gremmie@1 59 self.thumb.delete(save=False)
gremmie@1 60
gremmie@1 61 parser = ImageFile.Parser()
gremmie@1 62 for chunk in self.photo.chunks():
gremmie@1 63 parser.feed(chunk)
gremmie@1 64 image = parser.close()
gremmie@1 65 format = image.format
gremmie@1 66 image = scale_image(image)
gremmie@1 67 s = StringIO()
gremmie@1 68 image.save(s, format)
gremmie@1 69 thumb_name = os.path.basename(self.photo.path)
gremmie@1 70 self.thumb.save(thumb_name, ContentFile(s.getvalue()), save=False)
gremmie@1 71
bgneal@491 72 def ogp_tags(self):
bgneal@491 73 """
bgneal@491 74 Returns a dict of Open Graph Protocol meta tags.
bgneal@491 75
bgneal@491 76 """
bgneal@491 77 desc = "Photo of the day: %s." % self.caption
bgneal@491 78 return {
bgneal@491 79 'og:title': self.caption,
bgneal@491 80 'og:type': 'article',
bgneal@491 81 'og:url': self.get_absolute_url(),
bgneal@491 82 'og:image': self.photo.url,
bgneal@491 83 'og:description': desc,
bgneal@491 84 }
bgneal@491 85
gremmie@1 86
gremmie@1 87 class CurrentManager(models.Manager):
bgneal@515 88 """
bgneal@515 89 Manager for the Current model.
bgneal@515 90
bgneal@515 91 """
gremmie@1 92 def get_current_photo(self):
bgneal@515 93 """
bgneal@515 94 Retrieves the current photo object from the current record.
bgneal@515 95
bgneal@515 96 """
gremmie@1 97 try:
gremmie@1 98 c = self.get(pk=1)
gremmie@1 99 return c.potd
gremmie@1 100 except Current.DoesNotExist:
gremmie@1 101 return None
gremmie@1 102
gremmie@1 103 def get_current_id(self):
bgneal@515 104 """
bgneal@515 105 Returns the ID of the current POTD from the current record.
bgneal@515 106
bgneal@515 107 """
gremmie@1 108 potd = self.get_current_photo()
gremmie@1 109 if potd is not None:
gremmie@1 110 return potd.pk
gremmie@1 111 return None
gremmie@1 112
gremmie@1 113
gremmie@1 114 class Current(models.Model):
gremmie@1 115 """This model simply stores the current POTD."""
gremmie@1 116 potd = models.ForeignKey(Photo)
gremmie@1 117
gremmie@1 118 objects = CurrentManager()
gremmie@1 119
gremmie@1 120 def __unicode__(self):
gremmie@1 121 return self.potd.__unicode__()
gremmie@1 122
gremmie@1 123 class Meta:
gremmie@1 124 verbose_name_plural = 'Current'
gremmie@1 125
gremmie@1 126
gremmie@1 127 class SequenceManager(models.Manager):
bgneal@515 128 """
bgneal@515 129 Manager for the Sequence model.
bgneal@515 130
bgneal@515 131 """
gremmie@1 132 def insert_photo(self, photo_id):
bgneal@515 133 """
bgneal@515 134 Inserts the given photo_id just after the current photo so it
bgneal@515 135 will appear as tomorrow's POTD.
bgneal@515 136
bgneal@515 137 """
gremmie@1 138 current = Current.objects.get_current_id()
gremmie@1 139 if current is not None:
bgneal@330 140 s = self.get(pk=1)
bgneal@330 141 seq = [int(x) for x in s.seq.split(',')]
bgneal@330 142 if photo_id not in seq:
bgneal@330 143 i = seq.index(current)
bgneal@330 144 seq.insert(i + 1, photo_id)
bgneal@330 145 s.seq = ','.join([str(x) for x in seq])
bgneal@330 146 s.save()
gremmie@1 147
gremmie@1 148 def remove_photo(self, photo_id):
bgneal@515 149 """
bgneal@515 150 Removes a given photo id from the sequence of photos.
bgneal@515 151
bgneal@515 152 """
gremmie@1 153 try:
gremmie@1 154 s = self.get(pk=1)
bgneal@330 155 except Sequence.DoesNotExist:
bgneal@330 156 pass
bgneal@330 157 else:
gremmie@1 158 seq = [int(x) for x in s.seq.split(',')]
gremmie@1 159 if photo_id in seq:
gremmie@1 160 seq.remove(photo_id)
gremmie@1 161 s.seq = ','.join([str(x) for x in seq])
gremmie@1 162 s.save()
gremmie@1 163
gremmie@1 164
gremmie@1 165 class Sequence(models.Model):
gremmie@1 166 """This model stores the sequence of photos for the POTD."""
gremmie@1 167 seq = models.CommaSeparatedIntegerField(max_length=4096)
gremmie@1 168
gremmie@1 169 objects = SequenceManager()
gremmie@1 170
gremmie@1 171 def __unicode__(self):
gremmie@1 172 return self.seq
gremmie@1 173
gremmie@1 174 class Meta:
gremmie@1 175 verbose_name_plural = 'Sequence'