-
-# 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.utcnow().replace(tzinfo=utc) - 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.keys() + [
- '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.extra_info
-
- 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).iterator():
- 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')).iterator()]
-
- elif field == 'author':
- obj[field] = ", ".join(t.name for t in book.tags.filter(category='author').iterator())
-
- 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), tz)
- 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).iterator():
- 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).iterator():
- 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]).iterator()]
-
- 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), tz)
- 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).iterator():
- # 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).iterator():
- 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)
-
-