+ return rc.NOT_FOUND
+
+ @classmethod
+ def href(cls, fragment):
+ """ Returns URI in the API for the fragment. """
+
+ return API_BASE + reverse("api_fragment",
+ args=[fragment.book.slug, fragment.anchor])
+
+ @classmethod
+ def url(cls, fragment):
+ """ Returns URL on the site for the fragment. """
+
+ return WL_BASE + fragment.get_absolute_url()
+
+ @classmethod
+ def themes(cls, fragment):
+ """ Returns a list of theme tags for the fragment. """
+
+ return fragment.tags.filter(category='theme')
+
+
+
+
+# Changes handlers
+
+class CatalogueHandler(BaseHandler):
+
+ @staticmethod
+ def fields(request, name):
+ fields_str = request.GET.get(name) if request is not None else None
+ return fields_str.split(',') if fields_str is not None else None
+
+ @staticmethod
+ def until(t=None):
+ """ Returns time suitable for use as upper time boundary for check.
+
+ Used to avoid issues with time between setting the change stamp
+ and actually saving the model in database.
+ Cuts the microsecond part to avoid issues with DBs where time has
+ more precision.
+
+ :param datetime t: manually sets the upper boundary
+
+ """
+ # set to five minutes ago, to avoid concurrency issues
+ if t is None:
+ t = datetime.now() - timedelta(seconds=settings.API_WAIT)
+ # set to whole second in case DB supports something smaller
+ return t.replace(microsecond=0)
+
+ @staticmethod
+ def book_dict(book, fields=None):
+ all_fields = ['url', 'title', 'description',
+ 'gazeta_link', 'wiki_link',
+ ] + Book.formats + BookMedia.formats + [
+ 'parent', 'parent_number',
+ 'tags',
+ 'license', 'license_description', 'source_name',
+ 'technical_editors', 'editors',
+ 'author', 'sort_key',
+ ]
+ if fields:
+ fields = (f for f in fields if f in all_fields)
+ else:
+ fields = all_fields
+
+ extra_info = book.get_extra_info_value()
+
+ obj = {}
+ for field in fields:
+
+ if field in Book.formats:
+ f = getattr(book, field+'_file')
+ if f:
+ obj[field] = {
+ 'url': f.url,
+ 'size': f.size,
+ }
+
+ elif field in BookMedia.formats:
+ media = []
+ for m in book.media.filter(type=field):
+ media.append({
+ 'url': m.file.url,
+ 'size': m.file.size,
+ })
+ if media:
+ obj[field] = media
+
+ elif field == 'url':
+ obj[field] = book.get_absolute_url()
+
+ elif field == 'tags':
+ obj[field] = [t.id for t in book.tags.exclude(category__in=('book', 'set'))]
+
+ elif field == 'author':
+ obj[field] = ", ".join(t.name for t in book.tags.filter(category='author'))
+
+ elif field == 'parent':
+ obj[field] = book.parent_id
+
+ elif field in ('license', 'license_description', 'source_name',
+ 'technical_editors', 'editors'):
+ f = extra_info.get(field)
+ if f:
+ obj[field] = f
+
+ else:
+ f = getattr(book, field)
+ if f:
+ obj[field] = f
+
+ obj['id'] = book.id
+ return obj
+
+ @classmethod
+ def book_changes(cls, request=None, since=0, until=None, fields=None):
+ since = datetime.fromtimestamp(int(since))
+ until = cls.until(until)
+
+ changes = {
+ 'time_checked': timestamp(until)
+ }
+
+ if not fields:
+ fields = cls.fields(request, 'book_fields')
+
+ added = []
+ updated = []
+ deleted = []
+
+ last_change = since
+ for book in Book.objects.filter(changed_at__gte=since,
+ changed_at__lt=until):
+ book_d = cls.book_dict(book, fields)
+ updated.append(book_d)
+ if updated:
+ changes['updated'] = updated
+
+ for book in Deleted.objects.filter(content_type=Book,
+ deleted_at__gte=since,
+ deleted_at__lt=until,
+ created_at__lt=since):
+ deleted.append(book.id)
+ if deleted:
+ changes['deleted'] = deleted
+
+ return changes
+
+ @staticmethod
+ def tag_dict(tag, fields=None):
+ all_fields = ('name', 'category', 'sort_key', 'description',
+ 'gazeta_link', 'wiki_link',
+ 'url', 'books',
+ )
+
+ if fields:
+ fields = (f for f in fields if f in all_fields)
+ else:
+ fields = all_fields
+
+ obj = {}
+ for field in fields:
+
+ if field == 'url':
+ obj[field] = tag.get_absolute_url()
+
+ elif field == 'books':
+ obj[field] = [b.id for b in Book.tagged_top_level([tag])]
+
+ elif field == 'sort_key':
+ obj[field] = tag.sort_key
+
+ else:
+ f = getattr(tag, field)
+ if f:
+ obj[field] = f
+
+ obj['id'] = tag.id
+ return obj
+
+ @classmethod
+ def tag_changes(cls, request=None, since=0, until=None, fields=None, categories=None):
+ since = datetime.fromtimestamp(int(since))
+ until = cls.until(until)
+
+ changes = {
+ 'time_checked': timestamp(until)
+ }
+
+ if not fields:
+ fields = cls.fields(request, 'tag_fields')
+ if not categories:
+ categories = cls.fields(request, 'tag_categories')
+
+ all_categories = ('author', 'epoch', 'kind', 'genre')
+ if categories:
+ categories = (c for c in categories if c in all_categories)
+ else:
+ categories = all_categories
+
+ updated = []
+ deleted = []
+
+ for tag in Tag.objects.filter(category__in=categories,
+ changed_at__gte=since,
+ changed_at__lt=until):
+ # only serve non-empty tags
+ if tag.book_count:
+ tag_d = cls.tag_dict(tag, fields)
+ updated.append(tag_d)
+ elif tag.created_at < since:
+ deleted.append(tag.id)
+ if updated:
+ changes['updated'] = updated
+
+ for tag in Deleted.objects.filter(category__in=categories,
+ content_type=Tag,
+ deleted_at__gte=since,
+ deleted_at__lt=until,
+ created_at__lt=since):
+ deleted.append(tag.id)
+ if deleted:
+ changes['deleted'] = deleted
+
+ return changes
+
+ @classmethod
+ def changes(cls, request=None, since=0, until=None, book_fields=None,
+ tag_fields=None, tag_categories=None):
+ until = cls.until(until)
+ since = int(since)
+
+ if not since:
+ cache = get_cache('api')
+ key = hash((book_fields, tag_fields, tag_categories,
+ tuple(sorted(request.GET.items()))
+ ))
+ value = cache.get(key)
+ if value is not None:
+ return value
+
+ changes = {
+ 'time_checked': timestamp(until)
+ }
+
+ changes_by_type = {
+ 'books': cls.book_changes(request, since, until, book_fields),
+ 'tags': cls.tag_changes(request, since, until, tag_fields, tag_categories),
+ }
+
+ for model in changes_by_type:
+ for field in changes_by_type[model]:
+ if field == 'time_checked':
+ continue
+ changes.setdefault(field, {})[model] = changes_by_type[model][field]
+
+ if not since:
+ cache.set(key, changes)
+
+ return changes
+
+
+class BookChangesHandler(CatalogueHandler):
+ allowed_methods = ('GET',)
+
+ @piwik_track
+ def read(self, request, since):
+ return self.book_changes(request, since)
+
+
+class TagChangesHandler(CatalogueHandler):
+ allowed_methods = ('GET',)
+
+ @piwik_track
+ def read(self, request, since):
+ return self.tag_changes(request, since)
+
+
+class ChangesHandler(CatalogueHandler):
+ allowed_methods = ('GET',)
+
+ @piwik_track
+ def read(self, request, since):
+ return self.changes(request, since)
+
+
+class PictureHandler(BaseHandler):
+ model = Picture
+ fields = ('slug', 'title')
+ allowed_methods = ('POST',)