alternative: isolation=SERIALIZABLE [chapter_07_aggregate_ends]

hjwp · hjwp · commit dfaa46ac4c6f · 2021-02-24T12:37:19.000Z
diff --git a/src/allocation/adapters/repository.py b/src/allocation/adapters/repository.py
@@ -20,9 +20,4 @@ def add(self, product):
         self.session.add(product)
 
     def get(self, sku):
-        return (
-            self.session.query(model.Product)
-            .filter_by(sku=sku)
-            .with_for_update()
-            .first()
-        )
+        return self.session.query(model.Product).filter_by(sku=sku).first()
diff --git a/src/allocation/service_layer/unit_of_work.py b/src/allocation/service_layer/unit_of_work.py
@@ -30,6 +30,7 @@ def rollback(self):
 DEFAULT_SESSION_FACTORY = sessionmaker(
     bind=create_engine(
         config.get_postgres_uri(),
+        isolation_level="REPEATABLE READ",
     )
 )
 

Original file line number	Diff line number	Diff line change
`@@ -30,6 +30,7 @@ def rollback(self):`
`30`	`30`	`DEFAULT_SESSION_FACTORY = sessionmaker(`
`31`	`31`	`bind=create_engine(`
`32`	`32`	`config.get_postgres_uri(),`
	`33`	`+ isolation_level="REPEATABLE READ",`
`33`	`34`	`)`
`34`	`35`	`)`
`35`	`36`