catalogue/publish.py

   1 # -*- coding: utf-8
   2 from django.core.files import File
   3 from django.core.urlresolvers import reverse
   4 from librarian import DocProvider, IOFile
   5 from librarian.pyhtml import EduModuleFormat
   6 from librarian.pypdf import EduModulePDFFormat
   7 from .models import Lesson, Attachment
   8 from fnpdjango.utils.text.slughifi import slughifi
   9
  10
  11 # TODO: Using sorl.thumbnail for now,
  12 # but this should be done in Librarian,
  13 # directly using convert or PIL as a fallback.
  14 def get_image(src_img_path, width=None, default_width=1600, formats=('PNG', 'JPEG', 'GIF')):
  15     """ Returns an object with `url` and `storage` attributes,
  16         or None if using the original image is OK.
  17     """
  18
  19     from PIL import Image
  20     from sorl.thumbnail import get_thumbnail
  21
  22     # Does it need converting?
  23     # Yes, if width is given explicitly.
  24     convert = width is not None
  25     if not convert:
  26         # Looks like it doesn't need converting.
  27         # But let's try opening it and checking its type.
  28         try:
  29             simg = Image.open(src_img_path)
  30         except IOError:
  31             # It doesn't look like image,
  32             # but maybe it's convertable to one.
  33             convert = True
  34         else:
  35             if simg.format not in formats:
  36                 # It's an image, but it's in some weird format.
  37                 convert = True
  38                 width = simg.size[0]
  39
  40     if convert:
  41         if width is None:
  42             width = default_width
  43         try:
  44             return get_thumbnail(src_img_path, '%sx%s' % (width, 10*width))
  45         except:
  46             # hard to predict what solr raises on invalid image
  47             return None
  48     else:
  49         return None
  50
  51
  52 class HtmlFormat(EduModuleFormat):
  53     IMAGE_FORMATS = ('PNG', 'JPEG', 'GIF')
  54     DEFAULT_IMAGE_WIDTH = 1600
  55
  56     def find_attachment(self, slug, fmt):
  57         lesson_slug = self.wldoc.book_info.url.slug
  58         try:
  59             # If already saved, use it.
  60             att = Attachment.objects.get(lesson__slug=lesson_slug,
  61                                          slug=slug, ext=fmt)
  62         except Attachment.DoesNotExist, e:
  63             # If attached to source IOFile, save now.
  64             att_name = "%s.%s" % (slug, fmt)
  65             try:
  66                 att_file = self.wldoc.source.attachments[att_name]
  67             except KeyError:
  68                 print u"ATTACHMENT MISSING:", att_name
  69                 raise self.MaterialNotFound()
  70             else:
  71                 lesson = Lesson.objects.get(slug=lesson_slug)
  72                 att = lesson.attachment_set.create(slug=slug, ext=fmt)
  73                 att.file.save(att_name, File(att_file.get_file()))
  74                 return att
  75         else:
  76             return att
  77
  78     def url_for_material(self, slug, fmt):
  79         return self.find_attachment(slug, fmt).file.url
  80
  81     def url_for_image(self, slug, fmt, width=None):
  82         try:
  83             src_img = self.find_attachment(slug, fmt).file
  84         except self.MaterialNotFound:
  85             return ''
  86         img = get_image(src_img.path, width, self.DEFAULT_IMAGE_WIDTH, self.IMAGE_FORMATS)
  87         return (img or src_img).url
  88
  89     def text_to_anchor(self, text):
  90         return slughifi(text)
  91
  92     def get_forma_url(self, forma):
  93         return '%s#%s' % (
  94             reverse('catalogue_lesson', args=['metody']),
  95             self.text_to_anchor(forma)
  96         )
  97
  98     def get_help_url(self, naglowek):
  99         return '%s%s#%s' % (
 100             '//edukacjamedialna.edu.pl',
 101             reverse('info', args=['jak-korzystac/']),
 102             self.naglowek_to_anchor(naglowek)
 103         )
 104
 105
 106 class PdfFormat(EduModulePDFFormat):
 107     IMAGE_FORMATS = ('PNG', 'JPEG', 'GIF')
 108     DEFAULT_IMAGE_WIDTH = 1600
 109
 110     def get_image(self, name):
 111         src_img = super(PdfFormat, self).get_image(name)
 112         img = get_image(
 113             src_img.get_filename(),
 114             default_width=self.DEFAULT_IMAGE_WIDTH,
 115             formats=self.IMAGE_FORMATS)
 116         if img:
 117             return IOFile.from_filename(img.storage.path(img))
 118         else:
 119             return src_img
 120
 121
 122 class OrmDocProvider(DocProvider):
 123     def by_slug(self, slug):
 124         """Should return a file-like object with a WL document XML."""
 125         return IOFile.from_filename(Lesson.objects.get(slug=slug).xml_file.path)