updating pagination

gracedb/superevents/api/paginators.py

 from rest_framework import pagination
 from rest_framework.response import Response
 
+import urllib
 from collections import OrderedDict
 
 import logging
 logger = logging.getLogger(__name__)
 
+# TP (30 Apr 2018):
+# This module has a bunch of hacked together pagination which is intended
+# to match the existing "pagination" of the events API.  We should definitely
+# redo both APIs to do something reasonable and consistent when we have a
+# chance.
+
 
 def BasePaginationFactory(links_dict=True, results_name='results'):
     class CustomBasePagination(pagination.PageNumberPagination):
@@ -53,3 +60,37 @@ class CustomLogTagPagination(pagination.PageNumberPagination):
         ])
 
         return Response(output)
+
+
+class CustomSupereventPagination(pagination.LimitOffsetPagination):
+    default_limit = 3
+    limit_query_param = 'count'
+    offset_query_param = 'start'
+
+    def get_paginated_response(self, data):
+        numRows = self.count
+
+        # Get base URI
+        base_uri = self.request.build_absolute_uri(self.request.path)
+
+        # Construct custom link for "last" page
+        last = max(0, (numRows / self.limit)) * self.limit
+        param_dict = {
+            'start': last,
+            self.limit_query_param: self.limit,
+        }
+        last_uri = base_uri + '?' + urllib.urlencode(param_dict)
+
+        output = OrderedDict([
+            ('numRows', numRows),
+            ('superevents', data),
+            ('links',
+                OrderedDict([
+                    ('self', self.request.build_absolute_uri()),
+                    ('next', self.get_next_link()),
+                    ('previous', self.get_previous_link()),
+                    ('first', base_uri),
+                    ('last', last_uri),
+                ])),
+        ])
+        return Response(output)

gracedb/superevents/api/views.py

@@ -24,7 +24,7 @@ from events.api.backends import LigoAuthentication
 
 from .mixins import GetParentSupereventMixin
 from .paginators import BasePaginationFactory, CustomLabelPagination, \
-    CustomLogTagPagination
+    CustomLogTagPagination, CustomSupereventPagination
 from .serializers import SupereventSerializer, SupereventUpdateSerializer, \
     SupereventEventSerializer, SupereventLabelSerializer, \
     SupereventLogSerializer, SupereventLogTagSerializer, \
@@ -44,7 +44,7 @@ class SupereventViewSet(viewsets.ModelViewSet):
     """
     queryset = Superevent.objects.all()
     serializer_class = SupereventSerializer
-    pagination_class = BasePaginationFactory(results_name='superevents')
+    pagination_class = CustomSupereventPagination
     lookup_field = SUPEREVENT_LOOKUP_FIELD
     lookup_value_regex = SUPEREVENT_LOOKUP_REGEX