From 0404a369188a9392e21b3431077466c0419fa63c Mon Sep 17 00:00:00 2001
From: sandronadiradze <sandro.nadiradze@makingscience.com>
Date: Sat, 2 Nov 2024 07:27:52 +0400
Subject: [PATCH] chore: start using more efficient queries for auction
 retrieve view

---
 auction/serializers.py | 15 +++++++--------
 auction/views.py       | 43 +++++++++++++++++++++++++-----------------
 2 files changed, 33 insertions(+), 25 deletions(-)

diff --git a/auction/serializers.py b/auction/serializers.py
index c193a77..8da285e 100644
--- a/auction/serializers.py
+++ b/auction/serializers.py
@@ -143,15 +143,14 @@ def get_category(self, obj):
     def get_statistics(self, obj):
         if obj.status == StatusChoices.DRAFT:
             return None
-        auction_statistics = AuctionStatistics.objects.filter(auction=obj.id).first()
         return {
-            "winner_bid": auction_statistics.winner_bid,
-            "winner_bid_author": auction_statistics.winner_bid_author,
-            "top_bid": auction_statistics.top_bid,
-            "top_bid_author": auction_statistics.top_bid_author,
-            "views_count": auction_statistics.views_count,
-            "total_bids_count": auction_statistics.total_bids_count,
-            "bookmarks_count": auction_statistics.bookmarks_count,
+            "winner_bid": obj.statistics.winner_bid,
+            "winner_bid_author": obj.statistics.winner_bid_author,
+            "top_bid": obj.statistics.top_bid,
+            "top_bid_author": obj.statistics.top_bid_author,
+            "views_count": obj.statistics.views_count,
+            "total_bids_count": obj.statistics.total_bids_count,
+            "bookmarks_count": obj.statistics.bookmarks_count,
         }
 
     def to_representation(self, instance):
diff --git a/auction/views.py b/auction/views.py
index e38f67b..5fa31d9 100755
--- a/auction/views.py
+++ b/auction/views.py
@@ -477,21 +477,30 @@ def get_object(self):
         user_is_seller = self.request.user.is_seller
 
         try:
-            # Base query with bookmark annotation
-            base_query = Auction.objects.annotate(
-                bookmark_id=Subquery(
-                    Bookmark.objects.filter(
-                        user_id=user_id, auction_id=OuterRef("pk")
-                    ).values("id")[:1]
-                ),
-                bookmarked=Case(
-                    When(bookmark_id__isnull=False, then=True),
-                    default=False,
-                    output_field=BooleanField(),
-                ),
+            # Base query with all necessary relations and annotations
+            base_query = (
+                Auction.objects.select_related(
+                    "statistics",
+                    "category",
+                )
+                .prefetch_related(
+                    "tags",
+                )
+                .annotate(
+                    bookmark_id=Subquery(
+                        Bookmark.objects.filter(
+                            user_id=user_id, auction_id=OuterRef("pk")
+                        ).values("id")[:1]
+                    ),
+                    bookmarked=Case(
+                        When(bookmark_id__isnull=False, then=True),
+                        default=False,
+                        output_field=BooleanField(),
+                    ),
+                )
             )
 
-            # bid-related annotations only for users with user_type of Seller
+            # bid-related annotations only for sellers
             if user_is_seller:
                 base_query = base_query.annotate(
                     has_bid=Exists(
@@ -499,13 +508,13 @@ def get_object(self):
                     ),
                 )
 
-            # Getting the auction with appropriate/combined annotations
+            # Get the auction with a single query
             auction = base_query.get(id=self.kwargs["id"])
 
             # Increment views count for the auction
-            AuctionStatistics.objects.filter(auction=auction.id).update(
-                views_count=F("views_count") + 1
-            )
+            auction.statistics.views_count = F("views_count") + 1
+            auction.statistics.save(update_fields=["views_count"])
+            auction.statistics.refresh_from_db()
 
             # Handle draft auction access based on user permissions
             if auction.status == StatusChoices.DRAFT: