Struct EventBus

pub struct EventBus { /* private fields */ }

Event bus

Asynchronously handles events of arbitrary Any type by passing them in-order to a set of registered async ‘handler’ functions. Handlers are processes in an unordered fashion, but an event is fully handled by all handlers until the next event in the posted event stream is processed.

Implementations

impl EventBus

pub fn new() -> Self

Create a new EventBus

pub async fn startup(&self) -> Result<(), StartupLockAlreadyStartedError>

Start up the EventBus background processor

pub async fn shutdown(&self)

Shut down EventBus background processing This unregisters all handlers as well and discards any unprocessed events

pub fn post<E: Any + Send + Sync + 'static>( &self, evt: E, ) -> Result<(), StartupLockNotStartedError>

Post an event to be processed

pub fn subscribe<E: Any + Send + Sync + 'static, F: Fn(Arc<E>) -> SendPinBoxFuture<()> + Send + Sync + 'static>( &self, handler: F, ) -> EventBusSubscription

Subscribe a handler to handle all posted events of a particular type Returns an subscription object that can be used to cancel this specific subscription if desired

pub fn unsubscribe(&self, sub: EventBusSubscription)

Given a subscription object returned from subscribe, removes the subscription for the EventBus. The handler will no longer be called.

pub fn len(&self) -> usize

Returns the number of unprocessed events remaining

pub fn is_empty(&self) -> bool

Checks if the bus has no events

Trait Implementations

impl Clone for EventBus

fn clone(&self) -> EventBus

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for EventBus

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for EventBus

fn default() -> Self

Returns the “default value” for a type.