Struct ClusterEventPublisher 

pub struct ClusterEventPublisher { /* private fields */ }

Deployment-global cluster-event broadcaster with a monotonic seq stamper.

Implementations

impl ClusterEventPublisher

pub fn new(capacity: NonZeroUsize) -> Self

Build a publisher over a fresh bounded broadcast channel of capacity.

capacity is the operator-configured websocket.cluster_broadcast_capacity (validated non-zero at startup), so this never receives a zero.

pub fn emit<F>(&self, build: F) -> ClusterEvent

where F: FnOnce(ClusterEventMeta) -> ClusterEvent,

Stamp and broadcast one cluster event.

build receives the publisher-allocated ClusterEventMeta (carrying the next monotonic cluster_seq and the observation instant) and returns the fully-formed event. The return value is the broadcast event (for tests); a send with no live subscribers is not an error (the calm single-node case has no dashboard attached).

pub fn subscribe( &self, after_seq: u64, ) -> BoxStream<'static, Result<ClusterEvent, ClusterStreamLagged>>

Subscribe to the live cluster delta stream, suppressing any delivered delta with cluster_seq <= after_seq.

after_seq dedups the splice seam: the cluster subscription attaches this receiver BEFORE reading the priming snapshot (gap-free splice), so the live stream may carry a delta the snapshot already reflects (one with cluster_seq <= snapshot.as_of_seq). Passing after_seq = as_of_seq suppresses exactly those already-applied deltas. Like every tokio broadcast receiver, this sees only events sent AFTER it attaches — there is no replay of pre-subscription history, which is why a lagged reconnect re-requests a full snapshot rather than resuming.

A receiver that falls behind the bounded buffer yields one Err(ClusterStreamLagged) with the skipped count and then closes — the same lag contract as the workflow path, surfaced typed, never silent.

pub fn current_seq(&self) -> u64

The next cluster_seq that will be assigned (i.e. one past the last stamped). Used by the snapshot path to stamp as_of_seq consistently with the live stream the subscriber spliced onto.

Trait Implementations

impl Clone for ClusterEventPublisher

fn clone(&self) -> ClusterEventPublisher

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ClusterEventPublisher

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

Formats the value using the given formatter.