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 librarian.pdf_from_html import EduModulePdfFromHtmlFormat
   8 from .models import Lesson, Attachment
   9 from fnpdjango.utils.text.slughifi import slughifi
  10
  11
  12 # TODO: Using sorl.thumbnail for now,
  13 # but this should be done in Librarian,
  14 # directly using convert or PIL as a fallback.
  15 def get_image(src_img_path, width=None, default_width=1600, formats=('PNG', 'JPEG', 'GIF')):
  16     """ Returns an object with `url` and `storage` attributes,
  17         or None if using the original image is OK.
  18     """
  19
  20     from PIL import Image
  21     from sorl.thumbnail import get_thumbnail
  22
  23     # Does it need converting?
  24     # Yes, if width is given explicitly.
  25     convert = width is not None
  26     if not convert:
  27         # Looks like it doesn't need converting.
  28         # But let's try opening it and checking its type.
  29         try:
  30             simg = Image.open(src_img_path)
  31         except IOError:
  32             # It doesn't look like image,
  33             # but maybe it's convertable to one.
  34             convert = True
  35         else:
  36             if simg.format not in formats:
  37                 # It's an image, but it's in some weird format.
  38                 convert = True
  39                 width = simg.size[0]
  40
  41     if convert:
  42         if width is None:
  43             width = default_width
  44         try:
  45             return get_thumbnail(src_img_path, '%sx%s' % (width, 10*width))
  46         except:
  47             # hard to predict what solr raises on invalid image
  48             return None
  49     else:
  50         return None
  51
  52
  53 class HtmlFormat(EduModuleFormat):
  54     IMAGE_FORMATS = ('PNG', 'JPEG', 'GIF')
  55     DEFAULT_IMAGE_WIDTH = 1600
  56
  57     def find_attachment(self, slug, fmt):
  58         lesson_slug = self.wldoc.book_info.url.slug
  59         try:
  60             # If already saved, use it.
  61             att = Attachment.objects.get(lesson__slug=lesson_slug,
  62                                          slug=slug, ext=fmt)
  63         except Attachment.DoesNotExist, e:
  64             # If attached to source IOFile, save now.
  65             att_name = "%s.%s" % (slug, fmt)
  66             try:
  67                 att_file = self.wldoc.source.attachments[att_name]
  68             except KeyError:
  69                 print u"ATTACHMENT MISSING:", att_name
  70                 raise self.MaterialNotFound()
  71             else:
  72                 lesson = Lesson.objects.get(slug=lesson_slug)
  73                 att = lesson.attachment_set.create(slug=slug, ext=fmt)
  74                 att.file.save(att_name, File(att_file.get_file()))
  75                 return att
  76         else:
  77             return att
  78
  79     def url_for_material(self, slug, fmt):
  80         return self.find_attachment(slug, fmt).file.url
  81
  82     def url_for_image(self, slug, fmt, width=None):
  83         try:
  84             src_img = self.find_attachment(slug, fmt).file
  85         except self.MaterialNotFound:
  86             return ''
  87         img = get_image(src_img.path, width, self.DEFAULT_IMAGE_WIDTH, self.IMAGE_FORMATS)
  88         return (img or src_img).url
  89
  90     def text_to_anchor(self, text):
  91         return slughifi(text)
  92
  93     def get_forma_url(self, forma):
  94         return '%s#%s' % (
  95             reverse('catalogue_lesson', args=['metody']),
  96             self.text_to_anchor(forma)
  97         )
  98
  99     def get_help_url(self, naglowek):
 100         return '%s%s#%s' % (
 101             '//edukacjamedialna.edu.pl',
 102             reverse('info', args=['jak-korzystac/']),
 103             self.naglowek_to_anchor(naglowek)
 104         )
 105
 106
 107 class PdfFormat(EduModulePDFFormat):
 108     IMAGE_FORMATS = ('PNG', 'JPEG', 'GIF')
 109     DEFAULT_IMAGE_WIDTH = 1600
 110
 111     def get_image(self, name):
 112         src_img = super(PdfFormat, self).get_image(name)
 113         img = get_image(
 114             src_img.get_filename(),
 115             default_width=self.DEFAULT_IMAGE_WIDTH,
 116             formats=self.IMAGE_FORMATS)
 117         if img:
 118             return IOFile.from_filename(img.storage.path(img))
 119         else:
 120             return src_img
 121
 122
 123 class PdfFromHtmlFormat(EduModulePdfFromHtmlFormat):
 124     IMAGE_FORMATS = ('PNG', 'JPEG', 'GIF')
 125     DEFAULT_IMAGE_WIDTH = 1600
 126
 127     def find_attachment(self, slug, fmt):
 128         lesson_slug = self.wldoc.book_info.url.slug
 129         try:
 130             # If already saved, use it.
 131             att = Attachment.objects.get(lesson__slug=lesson_slug,
 132                                          slug=slug, ext=fmt)
 133         except Attachment.DoesNotExist, e:
 134             # If attached to source IOFile, save now.
 135             att_name = "%s.%s" % (slug, fmt)
 136             try:
 137                 att_file = self.wldoc.source.attachments[att_name]
 138             except KeyError:
 139                 print u"ATTACHMENT MISSING:", att_name
 140                 raise self.MaterialNotFound()
 141             else:
 142                 lesson = Lesson.objects.get(slug=lesson_slug)
 143                 att = lesson.attachment_set.create(slug=slug, ext=fmt)
 144                 att.file.save(att_name, File(att_file.get_file()))
 145                 return att
 146         else:
 147             return att
 148
 149     def url_for_material(self, slug, fmt):
 150         return self.find_attachment(slug, fmt).file.url
 151
 152     def image(self, slug, fmt, width=None):
 153         try:
 154             src_img = self.find_attachment(slug, fmt).file
 155         except self.MaterialNotFound:
 156             return None
 157         img = get_image(src_img.path, width, self.DEFAULT_IMAGE_WIDTH, self.IMAGE_FORMATS)
 158         return img or src_img
 159
 160     def url_for_image(self, slug, fmt, image=None, **kwargs):
 161         img = image or self.image(slug, fmt, **kwargs)
 162         if img:
 163             return img.url
 164         else:
 165             return ''
 166
 167     def text_to_anchor(self, text):
 168         return slughifi(text)
 169
 170
 171 class OrmDocProvider(DocProvider):
 172     def by_slug(self, slug):
 173         """Should return a file-like object with a WL document XML."""
 174         return IOFile.from_filename(Lesson.objects.get(slug=slug).xml_file.path)