An example of a trip reservation workflow, using the SAGAs pattern to undo previous steps in case of an error. This is a minimal version of the holiday reservation demo in the Restate Holiday Repository.
Durable Execution's guarantee to run code to the end in the presence of failures, and to deterministically recover previous steps from the journal, makes SAGAs easy. Every step pushes a compensation action (an undo operation) to a stack. in the case of an error, those operations are run.
The main requirement is that steps are implemented as journalled
operations, like ctx.run() (e.g., direct calls to 3rd party APIs) or
RPCs to other Restate-backed services (e.g., FlightsClient.fromContex(ctx)).