migrate session handling to aioweb_tls/refactoring of helpers

src/monitor_utils/database.py

@@ -99,7 +99,8 @@ async def add_products_to_database(
     price is lower (a drop) and cleared otherwise, so any price_before_drop on
     the incoming product is ignored. Prices are recorded in a pastPrices array
     of price/date entries; a price already present in the array is never
-    recorded again, so each distinct price keeps only its first-seen timestamp. New products and never-before-recorded prices
+    recorded again, so each distinct price keeps only its first-seen timestamp.
+    New products and never-before-recorded prices
     upsert an alert referencing the product; a price returning to a value
     already in pastPrices emits nothing, so per-source price oscillation
     (member vs non-member quotes for the same SKU) alerts once per distinct
@@ -119,6 +120,12 @@ async def add_products_to_database(
             product_id.
     """
 
+    # Callers are expected to filter empty batches, but guard here too: an empty
+    # products list would make collection.bulk_write([]) raise InvalidOperation,
+    # which callers would then log as a spurious category failure every cycle.
+    if not products:
+        return
+
     doc_ids = [
         build_doc_id(p.product_id, category_identifier, use_composite) for p in products
     ]
@@ -311,8 +318,10 @@ def build_doc_id(
 def convert_product_to_mongo(product: Product) -> dict:
     """Flatten a Product into its MongoDB document representation.
 
-    Coerces string prices to floats and stamps lastUpdated with the current
-    UTC time. The _id is assigned by the caller via build_doc_id.
+    Stamps lastUpdated with the current UTC time. Prices are already floats via
+    the Product's pydantic validation (numeric strings coerced, comma strings
+    rejected at construction), so no coercion happens here. The _id is assigned
+    by the caller via build_doc_id.
 
     Args:
         product: Product to convert.
@@ -328,9 +337,6 @@ def convert_product_to_mongo(product: Product) -> dict:
     availability = data["availability"]
     current_price = pricing["current_price"]
     original_price = pricing["original_price"]
-    if isinstance(current_price, str):
-        current_price = float(current_price.replace(",", ""))
-        original_price = float(original_price.replace(",", ""))
 
     return {
         "title": data["title"],