feat(Price Stats): Stats grouped by

open_prices/api/prices/filters.py

@@ -7,6 +7,12 @@ class PriceFilter(django_filters.FilterSet):
     product_id__isnull = django_filters.BooleanFilter(
         field_name="product_id", lookup_expr="isnull"
     )
+    product_labels_tags__contains = django_filters.CharFilter(
+        field_name="product__labels_tags", lookup_expr="icontains"
+    )
+    product_categories_tags__contains = django_filters.CharFilter(
+        field_name="product__categories_tags", lookup_expr="icontains"
+    )
     labels_tags__contains = django_filters.CharFilter(
         field_name="labels_tags", lookup_expr="icontains"
     )
@@ -52,4 +58,5 @@ class Meta:
             "date",
             "proof_id",
             "owner",
+            "proof__type",
         ]

open_prices/api/prices/serializers.py

@@ -64,3 +64,26 @@ class PriceStatsSerializer(serializers.Serializer):
     price__min = serializers.DecimalField(max_digits=10, decimal_places=2)
     price__max = serializers.DecimalField(max_digits=10, decimal_places=2)
     price__avg = serializers.DecimalField(max_digits=10, decimal_places=2)
+    price__sum = serializers.DecimalField(max_digits=10, decimal_places=2)
+
+
+class GroupedPriceStatsQuerySerializer(serializers.Serializer):
+    group_by = serializers.CharField(
+        required=True, help_text="Field by which to group the statistics"
+    )
+    order_by = serializers.CharField(
+        required=False, help_text="Field by which to order the results"
+    )
+
+
+class GroupedPriceStatsSerializer(PriceStatsSerializer):
+    # Override representation to dynamically include the group field
+    def to_representation(self, instance):
+        representation = super().to_representation(instance)
+
+        # Add the grouping field dynamically
+        for key in instance:
+            if key not in representation:  # It's likely the group field
+                representation[key] = instance[key]
+
+        return representation

open_prices/api/prices/views.py

@@ -1,5 +1,6 @@
+from django.core.exceptions import FieldError
 from django_filters.rest_framework import DjangoFilterBackend
-from drf_spectacular.utils import extend_schema
+from drf_spectacular.utils import OpenApiParameter, extend_schema
 from rest_framework import filters, mixins, status, viewsets
 from rest_framework.decorators import action
 from rest_framework.permissions import IsAuthenticatedOrReadOnly
@@ -8,6 +9,8 @@
 
 from open_prices.api.prices.filters import PriceFilter
 from open_prices.api.prices.serializers import (
+    GroupedPriceStatsQuerySerializer,
+    GroupedPriceStatsSerializer,
     PriceCreateSerializer,
     PriceFullSerializer,
     PriceStatsSerializer,
@@ -79,3 +82,41 @@ def create(self, request: Request, *args, **kwargs):
     def stats(self, request: Request) -> Response:
         qs = self.filter_queryset(self.get_queryset())
         return Response(qs.calculate_stats(), status=200)
+
+    @extend_schema(
+        request=GroupedPriceStatsQuerySerializer,
+        responses=GroupedPriceStatsSerializer(many=True),
+        filters=True,
+        parameters=[
+            OpenApiParameter(
+                name="group_by",
+                description="Field by which to group the statistics",
+                required=True,
+                type=str,
+                location=OpenApiParameter.QUERY,
+            )
+        ],
+    )
+    @action(detail=False, methods=["GET"])
+    def grouped_stats(self, request: Request) -> Response:
+        qs = self.filter_queryset(self.get_queryset())
+
+        # Validate and parse query parameters using the serializer
+        serializer = GroupedPriceStatsQuerySerializer(data=request.query_params)
+        serializer.is_valid(raise_exception=True)
+        group_by = serializer.validated_data.get("group_by")
+        order_by = serializer.validated_data.get("order_by", None)
+
+        try:
+            data = qs.calculate_grouped_stats(group_by, order_by)
+        except FieldError:
+            return Response(
+                {"detail": f"Invalid group_by field: {group_by}"},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        # Apply pagination
+        paginator = self.paginator  # Use the default pagination class
+        paginated_data = paginator.paginate_queryset(data, request, view=self)
+
+        return paginator.get_paginated_response(paginated_data)

open_prices/prices/models.py

@@ -3,8 +3,8 @@
 
 from django.core.validators import MinValueValidator, ValidationError
 from django.db import models
-from django.db.models import Avg, Count, F, Max, Min, signals
-from django.db.models.functions import Cast
+from django.db.models import Avg, Count, F, Max, Min, Sum, signals
+from django.db.models.functions import Cast, TruncMonth, TruncWeek, TruncYear
 from django.dispatch import receiver
 from django.utils import timezone
 from openfoodfacts.taxonomy import (
@@ -54,6 +54,38 @@ def calculate_stats(self):
                 Avg("price"),
                 output_field=models.DecimalField(max_digits=10, decimal_places=2),
             ),
+            price__sum=Sum("price"),
+        )
+
+    def calculate_grouped_stats(self, group_by, order_by):
+        group_by_list = group_by.split(",")
+        if (
+            "month" in group_by_list
+            or "year" in group_by_list
+            or "week" in group_by_list
+        ):
+            queryset = self.annotate(
+                month=TruncMonth("date"), year=TruncYear("date"), week=TruncWeek("date")
+            )
+        else:
+            queryset = self
+        if order_by:
+            order_by_list = [order_by]
+        else:
+            order_by_list = group_by_list
+        return (
+            queryset.values(*group_by_list)
+            .annotate(
+                price__count=Count("pk"),
+                price__min=Min("price"),
+                price__max=Max("price"),
+                price__avg=Cast(
+                    Avg("price"),
+                    output_field=models.DecimalField(max_digits=10, decimal_places=2),
+                ),
+                price__sum=Sum("price"),
+            )
+            .order_by(*order_by_list)
         )