Struct Gossip

pub struct Gossip { /* private fields */ }

Available on crate feature net only.

Publish and subscribe on gossiping topics.

Each topic is a separate broadcast tree with separate memberships.

A topic has to be joined before you can publish or subscribe on the topic. To join the swarm for a topic, you have to know the [PublicKey] of at least one peer that also joined the topic.

Messages published on the swarm will be delivered to all peers that joined the swarm for that topic. You will also be relaying (gossiping) messages published by other peers.

With the default settings, the protocol will maintain up to 5 peer connections per topic.

Even though the Gossip is created from a [Endpoint], it does not accept connections itself. You should run an accept loop on the [Endpoint] yourself, check the ALPN protocol of incoming connections, and if the ALPN protocol equals GOSSIP_ALPN, forward the connection to the gossip actor through Self::handle_connection.

The gossip actor will, however, initiate new connections to other peers by itself.

Implementations

impl Gossip

pub fn builder() -> Builder

Creates a default Builder, with the endpoint set.

pub fn max_message_size(&self) -> usize

Returns the maximum message size configured for this gossip actor.

pub async fn handle_connection(&self, conn: Connection) -> Result<(), Error>

Handles an incoming [Connection].

Make sure to check the ALPN protocol yourself before passing the connection.

pub async fn subscribe_and_join( &self, topic_id: TopicId, bootstrap: Vec<NodeId>, ) -> Result<GossipTopic, Error>

Joins a gossip topic with the default options and waits for at least one active connection to be established.

pub fn subscribe( &self, topic_id: TopicId, bootstrap: Vec<NodeId>, ) -> Result<GossipTopic, Error>

Joins a gossip topic with the default options.

Note that this will not wait for any bootstrap node to be available. To ensure the topic is connected to at least one node, use GossipTopic::joined or Gossip::subscribe_and_join

pub fn subscribe_with_opts( &self, topic_id: TopicId, opts: JoinOptions, ) -> GossipTopic

Joins a gossip topic with options.

Returns a GossipTopic instantly. To wait for at least one connection to be established, you can await GossipTopic::joined.

Messages will be queued until a first connection is available. If the internal channel becomes full, the oldest messages will be dropped from the channel.

pub fn subscribe_with_stream( &self, topic_id: TopicId, options: JoinOptions, updates: CommandStream, ) -> EventStream

Joins a gossip topic with options and an externally-created update stream.

This method differs from Self::subscribe_with_opts by letting you pass in a updates command stream yourself instead of using a channel created for you.

It returns a stream of events. If you want to wait for the topic to become active, wait for the first GossipEvent::NeighborUp.

impl Gossip

pub fn client(&self) -> &Client<FlumeConnector<Response, Request>>

Available on crate feature rpc only.

Get an in-memory gossip client

pub async fn handle_rpc_request<C: ChannelTypes<RpcService>>( self, msg: Request, chan: RpcChannel<RpcService, C>, ) -> Result<(), RpcServerError<C>>

Available on crate feature rpc only.

Handle a gossip request from the RPC server.

Trait Implementations

impl Clone for Gossip

fn clone(&self) -> Gossip

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Gossip

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

Formats the value using the given formatter.

impl ProtocolHandler for Gossip

fn accept(&self, conn: Connection) -> BoxFuture<Result<()>>

Handle an incoming connection.

fn on_connecting( &self, connecting: Connecting, ) -> Pin<Box<dyn Future<Output = Result<Connection, Error>> + Send>>

Optional interception point to handle the Connecting state.

fn shutdown(&self) -> Pin<Box<dyn Future<Output = ()> + Send>>

Called when the node shuts down.