Synchronous Transaction Rollback mediation primitive
You can use the Synchronous Transaction Rollback mediation primitive to roll back the current transaction and then continue processing the flow. The Synchronous Transaction Rollback can be used only in mediation flows that use a synchronous invocation style.
Introduction
The Synchronous Transaction Rollback primitive has one input terminal (in), one output terminal (out) and one fail terminal (fail). If you start the mediation flow using a synchronous invocation style and the Synchronous Transaction Rollback primitive is called, the current transaction is rolled back, the out terminal is fired, and flow processing continues. If you start the mediation flow using an asynchronous invocation style and the Synchronous Transaction Rollback primitive is called, the fail terminal is fired and an error shows which indicates that the Synchronous Transaction Rollback primitive has been called in an asynchronous flow. In this case, the transaction is not rolled back.
Another way of rolling back a transaction in a mediation flow is by using the Fail primitive, which stops the flow and sends an unmodelled fault back to the client. With the Synchronous Transaction Rollback primitive, you explicitly roll back the transaction and flow processing continues.
Usage
Use the Synchronous Transaction Rollback primitive if you want to explicitly roll back the current transaction in a mediation flow, as part of an error handling routine. For example, if an error has occurred when calling out to a target service, the Synchronous Transaction Rollback primitive can be used to roll back a change made to a database before the callout failed, and a modeled fault can be returned to the client.
You can use the Synchronous Transaction Rollback mediation primitive to roll back the current transaction under certain conditions. For example, if you wire an output terminal of a Message Filter mediation primitive to a Synchronous Transaction Rollback mediation primitive, the transaction is rolled back if the filter condition occurs.