apps/picture/models.py

   1 from django.db import models
   2 import catalogue.models
   3 from django.db.models import permalink
   4 from sorl.thumbnail import ImageField
   5 from django.conf import settings
   6 from django.core.files.storage import FileSystemStorage
   7 from django.utils.datastructures import SortedDict
   8 from django.template.loader import render_to_string
   9 from django.core.cache import cache
  10 from catalogue.utils import split_tags
  11 from django.utils.safestring import mark_safe
  12 from slughifi import slughifi
  13
  14 from django.utils.translation import ugettext_lazy as _
  15 from newtagging import managers
  16 from os import path
  17
  18
  19 picture_storage = FileSystemStorage(location=path.join(settings.MEDIA_ROOT, 'pictures'), base_url=settings.MEDIA_URL + "pictures/")
  20
  21
  22 class Picture(models.Model):
  23     """
  24     Picture resource.
  25
  26     """
  27     title       = models.CharField(_('title'), max_length=120)
  28     slug        = models.SlugField(_('slug'), max_length=120, db_index=True, unique=True)
  29     sort_key    = models.CharField(_('sort key'), max_length=120, db_index=True, editable=False)
  30     created_at  = models.DateTimeField(_('creation date'), auto_now_add=True, db_index=True)
  31     changed_at  = models.DateTimeField(_('creation date'), auto_now=True, db_index=True)
  32     xml_file    = models.FileField('xml_file', upload_to="xml", storage=picture_storage)
  33     image_file  = ImageField(_('image_file'), upload_to="images", storage=picture_storage)
  34     objects     = models.Manager()
  35     tagged      = managers.ModelTaggedItemManager(catalogue.models.Tag)
  36     tags        = managers.TagDescriptor(catalogue.models.Tag)
  37
  38     class AlreadyExists(Exception):
  39         pass
  40
  41     class Meta:
  42         ordering = ('sort_key',)
  43
  44         verbose_name = _('picture')
  45         verbose_name_plural = _('pictures')
  46
  47     def save(self, force_insert=False, force_update=False, reset_short_html=True, **kwargs):
  48         from sortify import sortify
  49
  50         self.sort_key = sortify(self.title)
  51
  52         ret = super(Picture, self).save(force_insert, force_update)
  53
  54         if reset_short_html:
  55             self.reset_short_html()
  56
  57         return ret
  58
  59     def __unicode__(self):
  60         return self.title
  61
  62     @permalink
  63     def get_absolute_url(self):
  64         return ('picture.views.picture_detail', [self.slug])
  65
  66     @classmethod
  67     def from_xml_file(cls, xml_file, image_file=None, overwrite=False):
  68         """
  69         Import xml and it's accompanying image file.
  70         If image file is missing, it will be fetched by librarian.picture.ImageStore
  71         which looks for an image file in the same directory the xml is, with extension matching
  72         its mime type.
  73         """
  74         from sortify import sortify
  75         from django.core.files import File
  76         from librarian.picture import WLPicture, ImageStore
  77         close_xml_file = False
  78         close_image_file = False
  79         # class SimpleImageStore(object):
  80         #     def path(self_, slug, mime_type):
  81         #         """Returns the image file. Ignores slug ad mime_type."""
  82         #         return image_file
  83
  84         if image_file is not None and not isinstance(image_file, File):
  85             image_file = File(open(image_file))
  86             close_image_file = True
  87
  88         if not isinstance(xml_file, File):
  89             xml_file = File(open(xml_file))
  90             close_xml_file = True
  91
  92         try:
  93             # use librarian to parse meta-data
  94             picture_xml = WLPicture.from_file(xml_file,
  95                                               image_store=ImageStore(picture_storage.path('images')))
  96                     # image_store=SimpleImageStore
  97
  98             picture, created = Picture.objects.get_or_create(slug=picture_xml.slug)
  99             if not created and not overwrite:
 100                 raise Picture.AlreadyExists('Picture %s already exists' % picture_xml.slug)
 101
 102             picture.title = picture_xml.picture_info.title
 103
 104             motif_tags = set()
 105             for part in picture_xml.partiter():
 106                 for motif in part['themes']:
 107                     tag, created = catalogue.models.Tag.objects.get_or_create(slug=slughifi(motif), category='theme')
 108                     if created:
 109                         tag.name = motif
 110                         tag.sort_key = sortify(tag.name)
 111                         tag.save()
 112                     motif_tags.add(tag)
 113
 114             picture.tags = catalogue.models.Tag.tags_from_info(picture_xml.picture_info) + \
 115                 list(motif_tags)
 116
 117             if image_file is not None:
 118                 img = image_file
 119             else:
 120                 img = picture_xml.image_file()
 121
 122             # FIXME: hardcoded extension
 123             picture.image_file.save(path.basename(picture_xml.image_path), File(img))
 124
 125             picture.xml_file.save("%s.xml" % picture.slug, File(xml_file))
 126             picture.save()
 127         finally:
 128             if close_xml_file:
 129                 xml_file.close()
 130             if close_image_file:
 131                 image_file.close()
 132         return picture
 133
 134     @classmethod
 135     def picture_list(cls, filter=None):
 136         """Generates a hierarchical listing of all pictures
 137         Pictures are optionally filtered with a test function.
 138         """
 139
 140         pics = cls.objects.all().order_by('sort_key')\
 141             .only('title', 'slug', 'image_file')
 142
 143         if filter:
 144             pics = pics.filter(filter).distinct()
 145
 146         pics_by_author = SortedDict()
 147         orphans = []
 148         for tag in catalogue.models.Tag.objects.filter(category='author'):
 149             pics_by_author[tag] = []
 150
 151         for pic in pics:
 152             authors = list(pic.tags.filter(category='author'))
 153             if authors:
 154                 for author in authors:
 155                     pics_by_author[author].append(pic)
 156             else:
 157                 orphans.append(pic)
 158
 159         return pics_by_author, orphans
 160
 161     @property
 162     def info(self):
 163         if not hasattr(self, '_info'):
 164             from librarian import dcparser
 165             from librarian import picture
 166             info = dcparser.parse(self.xml_file.path, picture.PictureInfo)
 167             self._info = info
 168         return self._info
 169
 170     def reset_short_html(self):
 171         if self.id is None:
 172             return
 173
 174         cache_key = "Picture.short_html/%d" % (self.id)
 175         cache.delete(cache_key)
 176
 177     def short_html(self):
 178         if self.id:
 179             cache_key = "Picture.short_html/%d" % (self.id)
 180             short_html = cache.get(cache_key)
 181         else:
 182             short_html = None
 183
 184         if short_html is not None:
 185             return mark_safe(short_html)
 186         else:
 187             tags = self.tags.filter(category__in=('author', 'kind', 'epoch'))
 188             tags = split_tags(tags)
 189
 190             short_html = unicode(render_to_string('picture/picture_short.html',
 191                 {'picture': self, 'tags': tags}))
 192
 193             if self.id:
 194                 cache.set(cache_key, short_html, catalogue.models.CACHE_FOREVER)
 195             return mark_safe(short_html)