Workflows And Sagas

A signup workflow is keyed by workflow id `signup/user-7`. A retry from the client submits the same workflow id again; the operator fears a second run.

A Restate workflow runs at most once per workflow id: a second submission with the same id attaches to the existing run and returns its result rather than starting a new execution. Choose a workflow id that encodes the business idempotency unit (the user / order being processed), so client retries …

A running workflow must accept an external 'payment confirmed' signal mid-flight. The integrator polls a database in a loop to detect it.

Expose a workflow signal as a shared handler (or awakeable) that external callers invoke by workflow id to deliver the event; the workflow awaits a durable promise for that signal and suspends until it arrives. Do not busy-poll — that holds resources and is non-durable. The signal handler and the m…

A client wants the current status and (when done) the result of workflow `signup/user-7` without re-running it.

Query the workflow by id: attach to its result promise (await its completion) or read a status exposed via a shared query handler that returns workflow state. The completed result is durable and returned to late attachers within the retention window. Do not infer status from side effects in another…