added resolving alerts collection

src/monitor_utils/database.py

@@ -34,6 +34,29 @@ def get_collection(collection_name: str) -> AsyncIOMotorCollection:
     return get_mongo_client()[MONGO_DATABASE_NAME][collection_name]
 
 
+def resolve_alerts_collection(
+    product_collection: AsyncIOMotorCollection,
+) -> AsyncIOMotorCollection:
+    """Return the alerts collection beside a product collection.
+
+    Alerts co-locate with the products they reference: the same database and
+    the same development mode. The mode is read from the product collection's
+    own name (setup_config appends a _testing suffix outside production), so a
+    monitor writing products to <name>_testing also writes alerts to
+    alerts_testing and the development bot draining alerts_testing sees them.
+
+    Args:
+        product_collection: The mode-resolved product collection the monitor
+            already writes to.
+
+    Returns:
+        The matching alerts collection in the same database and mode.
+    """
+
+    suffix = "_testing" if product_collection.name.endswith("_testing") else ""
+    return product_collection.database[f"alerts{suffix}"]
+
+
 @cache
 def get_mongo_client() -> AsyncIOMotorClient:
     """Return a cached Motor client configured for the shared cluster.
@@ -132,7 +155,7 @@ async def add_products_to_database(
     try:
         await collection.bulk_write(ops, ordered=False)
         if alert_ops:
-            await write_alert_ops(alert_ops)
+            await write_alert_ops(alert_ops, resolve_alerts_collection(collection))
     except PyMongoError:
         LOGGER.exception(
             "failed to add products to database",
@@ -142,7 +165,7 @@ async def add_products_to_database(
 
 
 async def write_alert_ops(
-    alert_ops: list[UpdateOne], alerts_collection_name: AsyncIOMotorCollection
+    alert_ops: list[UpdateOne], alerts_collection: AsyncIOMotorCollection
 ):
     """Write alert upserts, swallowing duplicate-key races.
 
@@ -154,12 +177,12 @@ async def write_alert_ops(
 
     Args:
         alert_ops: Alert upsert operations to write.
+        alerts_collection: The mode-resolved alerts collection to write to,
+            supplied by the caller so the writer stays mode-agnostic.
     """
 
     try:
-        await get_collection(alerts_collection_name).bulk_write(
-            alert_ops, ordered=False
-        )
+        await alerts_collection.bulk_write(alert_ops, ordered=False)
     except BulkWriteError as exc:
         real_errors = [
             write_error