SPIKE: Public API wildcard performance investigation

public_api/urls.py

@@ -16,7 +16,10 @@
     TopicDetailViewV2,
     TopicListViewV2,
 )
-from public_api.version_02.views.timeseries_viewset import APITimeSeriesViewSetV2
+from public_api.version_02.views.timeseries_viewset import (
+    APITimeSeriesViewSetV2,
+    APITimeSeriesViewSetV3,
+)
 from public_api.views import (
     GeographyDetailView,
     GeographyListView,
@@ -50,6 +53,7 @@ def construct_url_patterns_for_public_api(
     urls = []
     urls.extend(_construct_version_one_urls(prefix=prefix))
     urls.extend(_construct_version_two_urls(prefix=prefix))
+    urls.extend(_construct_version_three_urls(prefix=prefix))
 
     if MetricsPublicAPIInterface.is_auth_enabled():
         urls.append(
@@ -222,3 +226,28 @@ def _construct_version_two_urls(
             name="timeseries-list-v2",
         ),
     ]
+
+
+def _construct_version_three_urls(
+    *,
+    prefix: str,
+) -> list[resolvers.URLResolver]:
+    """Returns a list of URLResolvers for the public_api version 3
+
+    Args:
+        prefix: The prefix to add to the start of the url paths
+
+    Returns:
+        List of `URLResolver` objects each representing a
+        set of versioned URLS.
+    """
+
+    return [
+        path(
+            f"{prefix}v3/themes/<str:theme>",
+            APITimeSeriesViewSetV3.as_view(
+                {"get": "list"}, name=APITimeSeriesViewSetV3.name
+            ),
+            name="timeseries-list-v3",
+        ),
+    ]

public_api/version_02/views/timeseries_viewset.py

@@ -1,3 +1,4 @@
+import django_filters
 from django_filters.rest_framework import DjangoFilterBackend
 from drf_spectacular.utils import extend_schema
 from rest_framework import pagination, viewsets
@@ -101,3 +102,98 @@ def get_queryset(self):
             metric=self.kwargs["metric"],
             restrict_to_public=True,
         )
+
+
+class APITimeSeriesFilterSetv3(django_filters.FilterSet):
+    geography = django_filters.CharFilter(field_name="geography", lookup_expr="iexact")
+    geography_type = django_filters.CharFilter(
+        field_name="geography_type", lookup_expr="iexact"
+    )
+
+    class Meta:
+        model = MetricsPublicAPIInterface.get_api_timeseries_model()
+        fields = [
+            "sub_theme",
+            "topic",
+            "geography_type",
+            "geography",
+            "metric",
+            "stratum",
+            "sex",
+            "age",
+            "year",
+            "epiweek",
+            "date",
+            "in_reporting_delay_period",
+        ]
+
+
+@extend_schema(tags=[PUBLIC_API_TAG])
+class APITimeSeriesViewSetV3(viewsets.ReadOnlyModelViewSet):
+    """
+    This endpoint will provide the full timeseries of a slice of data.
+
+    There is one mandatory URL parameter and other optional query parameters:
+
+    Note that by default, results are paginated by a page size of 5
+
+    This page size can be changed using the *page_size* parameter.
+    The maximum supported page size is **365**.
+
+    ---
+
+    The mandatory URL parameter is:
+
+    - `theme` - The largest topical subgroup e.g. **infectious_disease**
+
+    ---
+
+    The optional query parameters are as follows in order from first to last:
+
+    - `sub_theme` - A topical subgroup e.g. **respiratory**
+
+    - `topic` - The name of the topic e.g. **COVID-19**
+
+    - `geography_type` - The type of the geography type e.g. **Nation**
+
+    - `geography` - The name of the geography associated with metric  e.g. **London**
+
+    - `metric` - The name of the metric being queried for e.g. **COVID-19_deaths_ONSByDay**
+
+    - `stratum` - Smallest subgroup a metric can be broken down into e.g. ethnicity, testing pillar
+
+    - `age` - Smallest subgroup a metric can be broken down into e.g. **15_44** for the age group of 15-44 years
+
+    - `sex` - Patient gender e.g. **f** for Female or **all** for all genders
+
+    - `year` - Epi year of the metrics value (important for annual metrics) e.g. **2020**
+
+    - `month` - Epi month of the metric value (important for monthly metrics) e.g. **12**
+
+    - `epiweek` - Epi week of the metric value (important for weekly metrics) e.g. **30**
+
+    - `date` - The date which this metric value was recorded in the format **YYYY-MM-DD** e.g. **2020-07-20**
+
+    - `in_reporting_delay_period` - A boolean indicating whether the data point is considered to be subject
+    to retrospective updates.
+
+    """
+
+    permission_classes = []
+    name = "API Time Series Version 3"
+    queryset = (
+        MetricsPublicAPIInterface.get_api_timeseries_model()
+        .objects.all()
+        .order_by("date")
+    )
+    serializer_class = APITimeSeriesListSerializerv2
+    pagination_class = APITimeSeriesPaginationv2
+    filter_backends = [DjangoFilterBackend]
+    filterset_class = APITimeSeriesFilterSetv3
+
+    def get_queryset(self):
+        queryset = super().get_queryset()
+
+        return queryset.filter(
+            theme=self.kwargs["theme"],
+        )

tests/unit/public_api/test_timeseries_viewset_v3.py

@@ -0,0 +1,43 @@
+import pytest
+from rest_framework.test import APIRequestFactory
+
+from public_api.version_02.views.timeseries_viewset import APITimeSeriesViewSetV3
+from tests.factories.metrics.api_models.time_series import APITimeSeriesFactory
+
+
+@pytest.mark.django_db
+class TestAPITimeSeriesViewSetV3GetQueryset:
+    def test_filters_queryset_by_theme_kwarg(self) -> None:
+        """
+        Ensure `get_queryset` applies the `theme` URL kwarg as a filter.
+        """
+        # Given: three records with different themes
+        infectious_record_1 = APITimeSeriesFactory.create_record(
+            theme_name="infectious_disease",
+            date="2023-01-01",
+        )
+        infectious_record_2 = APITimeSeriesFactory.create_record(
+            theme_name="infectious_disease",
+            date="2023-01-02",
+        )
+        APITimeSeriesFactory.create_record(
+            theme_name="extreme_event",
+        )
+
+        # And a view instance with the theme URL kwarg set
+        view = APITimeSeriesViewSetV3()
+        view.kwargs = {"theme": "infectious_disease"}
+
+        # DRF's GenericAPIView expects a `request` attribute, even though our
+        # overridden `get_queryset` does not use it directly.
+        view.request = APIRequestFactory().get("/<prefix>/v3/themes/infectious_disease")
+
+        # When
+        queryset = view.get_queryset()
+
+        # Then: only records matching the URL theme are returned
+        themes = {instance.theme for instance in queryset}
+        assert themes == {"infectious_disease"}
+        assert queryset.count() == 2
+        assert queryset.first() == infectious_record_1
+        assert queryset.last() == infectious_record_2