Add serializer and filter for last_changed endpoint

Add ability to override list view if the view itself doesn't return a list.

Author: Matt Daily

observation_portal/common/schema.py

@@ -1,13 +1,23 @@
 from rest_framework.schemas.openapi import AutoSchema
 
 class ObservationPortalSchema(AutoSchema):
-    def __init__(self, tags, operation_id_base=None, component_name=None, empty_request=False):
+    def __init__(self, tags, operation_id_base=None, component_name=None, empty_request=False, is_list_view=True):
         super().__init__(tags=tags, operation_id_base=operation_id_base, component_name=component_name)
         self.empty_request = empty_request
+        self.is_list_view = is_list_view
 
     def get_operation(self, path, method):
         operations =  super().get_operation(path, method)        
         if self.empty_request:
             operations['requestBody'] = {}
 
         return operations
+
+    def get_responses(self, path, method):
+        responses = super().get_responses(path, method)
+        if not self.is_list_view:
+            list_items = responses['200']['content']['application/json']['schema'].pop('items')
+            del responses['200']['content']['application/json']['schema']['type']
+            responses['200']['content']['application/json']['schema'] = list_items
+
+        return responses

observation_portal/requestgroups/filters.py

@@ -1,6 +1,6 @@
 import django_filters
 from observation_portal.requestgroups.models import RequestGroup, Request
-
+from observation_portal.common.configdb import configdb
 
 class RequestGroupFilter(django_filters.FilterSet):
     created_after = django_filters.DateTimeFilter(field_name='created', lookup_expr='gte', label='Submitted after')
@@ -67,3 +67,7 @@ class TelescopeAvailabilityFilter(django_filters.FilterSet):
 
     class Meta:
         fields = ('start', 'end', 'site', 'telescope', 'combine')
+
+
+class LastChangedFilter(django_filters.FilterSet):
+    telescope_class = django_filters.MultipleChoiceFilter(choices=configdb.get_telescope_class_tuples())

observation_portal/requestgroups/serializers.py

@@ -977,3 +977,6 @@ def to_internal_value(self, data):
         new_data = {'request': data}
         # do validation on the new request dict, then return it without the extra request key
         return super().to_internal_value(new_data)['request']
+
+class LastChangedSerializer(serializers.Serializer):
+    last_change_time = serializers.DateTimeField()

observation_portal/requestgroups/views.py

@@ -1,3 +1,5 @@
+from django.core.exceptions import ValidationError
+from observation_portal.common.schema import ObservationPortalSchema
 from django.core.cache import cache
 from django_filters.rest_framework.backends import DjangoFilterBackend
 from rest_framework.response import Response
@@ -17,7 +19,7 @@
 from observation_portal.common.telescope_states import ElasticSearchException, TelescopeStates
 from observation_portal.requestgroups.request_utils import get_airmasses_for_request_at_sites
 from observation_portal.requestgroups.contention import Contention, Pressure
-from observation_portal.requestgroups.filters import TelescopeAvailabilityFilter, TelescopeStatesFilter
+from observation_portal.requestgroups.filters import LastChangedFilter, TelescopeAvailabilityFilter, TelescopeStatesFilter
 from observation_portal.common.mixins import GetSerializerMixin
 
 logger = logging.getLogger(__name__)
@@ -176,17 +178,24 @@ def get(self, request):
         return Response(pressure.data())
 
 
-class ObservationPortalLastChangedView(APIView):
+class ObservationPortalLastChangedView(APIView, GetSerializerMixin):
     '''
         Returns the datetime of the last status of requests change or new requests addition
     '''
     permission_classes = (IsAdminUser,)
-    schema=AutoSchema(tags=['RequestGroups'])
+    schema=ObservationPortalSchema(tags=['RequestGroups'], is_list_view=False)
+    filter_class = LastChangedFilter
+    filter_backends = (DjangoFilterBackend,)
+    serializer_class = import_string(settings.SERIALIZERS['requestgroups']['LastChanged'])
 
     def get(self, request):
         telescope_classes = request.GET.getlist('telescope_class', ['all'])
         most_recent_change_time = timezone.now() - timedelta(days=7)
         for telescope_class in telescope_classes:
             most_recent_change_time = max(most_recent_change_time, cache.get(f"observation_portal_last_change_time_{telescope_class}", timezone.now() - timedelta(days=7)))
 
-        return Response({'last_change_time': most_recent_change_time})
+        serializer = import_string(settings.SERIALIZERS['requestgroups']['LastChanged'])(data={'last_change_time': most_recent_change_time})
+        if serializer.is_valid():
+            return Response(serializer.validated_data)
+        else:
+            raise ValidationError(serializer.errors)

observation_portal/settings.py

@@ -333,6 +333,7 @@ def get_list_from_env(variable, default=None):
         'Mosaic': os.getenv('REQUESTGROUPS_MOSAIC_SERIALIZER', 'observation_portal.requestgroups.serializers.MosaicSerializer'),
         'Dither': os.getenv('REQUESTGROUPS_DITHER_SERIALIZER', 'observation_portal.requestgroups.serializers.DitherSerializer'),
         'Airmass': os.getenv('REQUESTGROUPS_AIRMASS_SERIALIZER', 'observation_portal.requestgroups.serializers.AirmassSerializer'),
+        'LastChanged': os.getenv('REQUESTGROUPS_LAST_CHANGED_SERIALIZER', 'observation_portal.requestgroups.serializers.LastChangedSerializer'),
     },
     'proposals': {
         'Proposal': os.getenv('PROPOSALS_PROPOSAL_SERIALIZER', 'observation_portal.proposals.serializers.ProposalSerializer'),