Use event decorator

backend/test_observer/data_access/setup.py

@@ -1,9 +1,10 @@
 from os import environ
-from sqlalchemy import create_engine, event
+from sqlalchemy import create_engine
 from sqlalchemy.orm import sessionmaker
 
-from .models import Artefact
-from .validators import validate_artefact
+# We need to import this to enable event listeners
+import test_observer.data_access.validators  # noqa: F401
+
 
 DEFAULT_DB_URL = "postgresql+pg8000://postgres:password@test-observer-db:5432/postgres"
 DB_URL = environ.get("DB_URL", DEFAULT_DB_URL)
@@ -12,9 +13,6 @@
 SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 
 
-event.listen(Artefact, "before_insert", validate_artefact)
-
-
 # Dependency
 def get_db():
     db = SessionLocal()

backend/test_observer/data_access/validators.py

@@ -18,12 +18,13 @@
 #        Nadzeya Hutsko <[email protected]>
 """Functions to validate the whole models (not just specific field)"""
 
-from sqlalchemy import select
+from sqlalchemy import select, event
 from sqlalchemy.engine.base import Connection
 from sqlalchemy.orm import Mapper
 from .models import Stage, Family, Artefact
 
 
+@event.listens_for(Artefact, "before_insert")
 def validate_artefact(
     mapper: Mapper, connection: Connection, artefact: Artefact  # noqa: ARG001
 ) -> None: