@@ -0,0 +1,10 @@
+package cloudflow.daos;
+
+import cloudflow.models.FlowResponse;
+import java.util.List;
+import java.util.Optional;
+
+public interface FlowDao {
+  Optional<FlowResponse> getFlow(String flowId);
+  List<FlowResponse> getAllFlows(String projectId, String projectVersion);
+}
If other DAOs are returning a null in similar situations then I would recommend following the same model and return a null here when the flow is not found. For other interfaces we are adding in CF we decided not to return an `Optional` and throw an exception instead.