Support ordering attribute either on view or on pagination class for CursorPagination

This commit is contained in:
Tom Christie 2015-01-22 15:15:52 +00:00
parent 83a82b44a5
commit 408261ee02
2 changed files with 20 additions and 5 deletions

View File

@ -427,16 +427,16 @@ class LimitOffsetPagination(BasePagination):
class CursorPagination(BasePagination):
# Support case where ordering is already negative
# Support tuple orderings
# Support usage with OrderingFilter
# Determine how/if True, False and None positions work
cursor_query_param = 'cursor'
page_size = api_settings.PAGINATE_BY
invalid_cursor_message = _('Invalid cursor')
ordering = None
def paginate_queryset(self, queryset, request, view=None):
self.base_url = request.build_absolute_uri()
self.ordering = self.get_ordering()
self.ordering = self.get_ordering(view)
# Determine if we have a cursor, and if so then decode it.
encoded = request.query_params.get(self.cursor_query_param)
@ -600,11 +600,25 @@ class CursorPagination(BasePagination):
encoded = _encode_cursor(cursor)
return replace_query_param(self.base_url, self.cursor_query_param, encoded)
def get_ordering(self):
def get_ordering(self, view):
"""
Return a tuple of strings, that may be used in an `order_by` method.
"""
return ('created',)
ordering = getattr(view, 'ordering', getattr(self, 'ordering', None))
assert ordering is not None, (
'Using cursor pagination, but no ordering attribute was declared '
'on the view or on the pagination class.'
)
assert isinstance(ordering, (six.string_types, list, tuple)), (
'Invalid ordering. Expected string or tuple, but got {type}'.format(
type=type(ordering).__name__
)
)
if isinstance(ordering, six.string_types):
return (ordering,)
return ordering
def _get_position_from_instance(self, instance, ordering):
attr = getattr(instance, ordering[0])

View File

@ -459,6 +459,7 @@ class TestCursorPagination:
class ExamplePagination(pagination.CursorPagination):
page_size = 5
ordering = 'created'
self.pagination = ExamplePagination()
self.queryset = MockQuerySet([