Struct EngineSubscription 

pub struct EngineSubscription { /* private fields */ }

Subscription to protocol-neutral engine change events.

Returned by crate::Engine::subscribe. The subscription holds a slot permit until dropped — drop it promptly when the caller is done so other subscribers can join.

Implementations

impl EngineSubscription

pub async fn recv(&mut self) -> Result<ChangeEvent, SubscriptionRecvError>

Returns the next change event for this subscription.

Drains the replay queue first (in increasing event id order), then switches to the live broadcast stream. If the caller passed since to crate::Engine::subscribe, events with id <= since are filtered.

Errors

• SubscriptionRecvError::Closed when the engine shut down or the underlying channel closed. Terminal: subsequent calls keep returning Closed.
• SubscriptionRecvError::Lagged when the broadcast ring buffer overflowed and events were lost. Recoverable: the next call resumes with fresh events.