Struct Broadcaster 

pub struct Broadcaster {
    replica_id: String,
    config: BroadcastConfig,
    peers: BTreeSet<String>,
    seen: HashSet<Hash>,
    seen_order: VecDeque<Hash>,
    timestamp: u64,
    pending_events: VecDeque<BroadcastEvent>,
    peer_heads: HashMap<String, HashSet<Hash>>,
}

Gossip-based broadcaster for head dissemination.

The broadcaster maintains:

• A set of known peers
• A buffer of seen message IDs (for deduplication)
• Pending outgoing messages

Fields

replica_id: String

Our replica ID.

config: BroadcastConfig

Configuration.

peers: BTreeSet<String>

Known peers (BTreeSet for deterministic iteration order).

seen: HashSet<Hash>

Message IDs we’ve seen (for deduplication).

seen_order: VecDeque<Hash>

Order of seen messages (for LRU eviction).

timestamp: u64

Current logical timestamp.

pending_events: VecDeque<BroadcastEvent>

Pending events to be processed.

peer_heads: HashMap<String, HashSet<Hash>>

Track which peers have which heads (optimization).

Implementations

impl Broadcaster

pub fn new(replica_id: impl Into<String>) -> Self

Create a new broadcaster.

pub fn with_config( replica_id: impl Into<String>, config: BroadcastConfig, ) -> Self

Create a broadcaster with custom configuration.

pub fn replica_id(&self) -> &str

Get our replica ID.

pub fn add_peer(&mut self, peer: impl Into<String>)

Add a peer.

pub fn remove_peer(&mut self, peer: &str)

Remove a peer.

pub fn peers(&self) -> impl Iterator<Item = &String>

Get all known peers.

pub fn broadcast(&mut self, heads: Vec<Hash>)

Broadcast new heads to peers.

pub fn receive(&mut self, from: impl Into<String>, message: BroadcastMessage)

Receive a message from a peer.

pub fn poll_event(&mut self) -> Option<BroadcastEvent>

Get the next pending event.

pub fn has_pending_events(&self) -> bool

Check if there are pending events.

pub fn drain_events(&mut self) -> Vec<BroadcastEvent>

Get all pending events.

fn mark_seen(&mut self, id: Hash)

Mark a message as seen.

fn select_peers(&self, n: usize) -> Vec<String>

Select n random peers.

fn select_peers_excluding(&self, n: usize, exclude: &[&str]) -> Vec<String>

Select n random peers, excluding some.

pub fn stats(&self) -> BroadcastStats

Get statistics about the broadcaster.