modify flask app to use service layer [flask_app_using_service_layer]

Author: hjwp

Diff for: flask_app.py

@@ -6,32 +6,25 @@
 import model
 import orm
 import repository
+import services
 
 
 orm.start_mappers()
 get_session = sessionmaker(bind=create_engine(config.get_postgres_uri()))
 app = Flask(__name__)
 
 
-def is_valid_sku(sku, batches):
-    return sku in {b.sku for b in batches}
-
-
 @app.route("/allocate", methods=["POST"])
 def allocate_endpoint():
     session = get_session()
-    batches = repository.SqlAlchemyRepository(session).list()
+    repo = repository.SqlAlchemyRepository(session)
     line = model.OrderLine(
         request.json["orderid"], request.json["sku"], request.json["qty"],
     )
 
-    if not is_valid_sku(line.sku, batches):
-        return {"message": f"Invalid sku {line.sku}"}, 400
-
     try:
-        batchref = model.allocate(line, batches)
-    except model.OutOfStock as e:
+        batchref = services.allocate(line, repo, session)
+    except (model.OutOfStock, services.InvalidSku) as e:
         return {"message": str(e)}, 400
 
-    session.commit()
     return {"batchref": batchref}, 201