Struct WorkflowEngine 

pub struct WorkflowEngine<S: DurableStore> { /* private fields */ }

Drives workflow steps through the V1 Queue and records V2 Events.

Implementations

impl<S: DurableStore> WorkflowEngine<S>

pub fn new( queue: Queue, store: S, worker_id: String, lease_ttl: Duration, priority: Priority, ) -> Self

pub fn register_workflow( &self, workflow: Workflow, bodies: Vec<StepFunc>, ) -> Result<(), EngineError>

Registers a workflow’s step bodies without running anything, so a later recover call (after a process restart) has something to re-admit an interrupted step into.

pub async fn run( &self, workflow: Workflow, bodies: Vec<StepFunc>, ) -> Result<(), EngineError>

Runs all steps in order, recording events and honoring per-step retry policy.

Stops (without error) at the first step that enters StepStatus::Waiting — the workflow stays registered so a later Self::resume can continue it from that point.

pub async fn cancel( &self, workflow_id: &str, reason: String, ) -> Result<(), EngineError>

Unblocks a step in StepStatus::Waiting, supplying opaque input for its next run, then continues driving the remaining steps in order — stopping again if a later step also enters Waiting. Records Event::WorkflowCancelled and un-registers the workflow so the engine will not claim or schedule further steps.

Idempotent: if the workflow already has a terminal event (Event::WorkflowCompleted, Event::WorkflowFailed, or Event::WorkflowCancelled), returns Ok(()) without appending anything.

Cancellation does not abort a step attempt already pushed to the V1 Queue and executing in a worker — V1 has no in-flight abort. Side effects from that run may still occur. While driving steps, cancellation is observed at the next step boundary (and between retry attempts for the current step); a body already running on the queue is not stopped.

pub async fn resume( &self, workflow_id: &str, step_index: usize, input: String, ) -> Result<(), EngineError>

pub fn resume_input( &self, workflow_id: &str, step_index: usize, ) -> Option<String>

Opaque input from the most recent Event::StepResumed for this step in durable storage, if any.