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impl NetworkBehaviour for Behaviour {
type ConnectionHandler = THandler<kad::Behaviour<kad::store::MemoryStore>>;
type ToSwarm = Event;
fn handle_established_inbound_connection(
&mut self,
connection_id: libp2p::swarm::ConnectionId,
peer: PeerId,
local_addr: &libp2p::Multiaddr,
remote_addr: &libp2p::Multiaddr,
) -> Result<THandler<Self>, ConnectionDenied> {
self.kademlia.handle_established_inbound_connection(
connection_id,
peer,
local_addr,
remote_addr,
)
}
fn handle_established_outbound_connection(
&mut self,
connection_id: ConnectionId,
peer: PeerId,
addr: &libp2p::Multiaddr,
role_override: libp2p::core::Endpoint,
port_use: libp2p::core::transport::PortUse,
) -> Result<THandler<Self>, ConnectionDenied> {
self.kademlia.handle_established_outbound_connection(
connection_id,
peer,
addr,
role_override,
port_use,
)
}
fn on_swarm_event(&mut self, event: FromSwarm<'_>) {
// We need to manually add the address, because kademlia doesn't do this by default (yet)
// https://github.com/libp2p/rust-libp2p/issues/5313
match event {
FromSwarm::ConnectionEstablished(ConnectionEstablished {
peer_id,
failed_addresses,
..
}) => {
self.pending_peers.retain(|(pending_peer_id, addr), _| {
// Keep all entries for different peers
pending_peer_id != &peer_id
// OR keep same-peer entries that failed
|| failed_addresses.iter().any(|failed_addr| failed_addr == addr)
});
}
FromSwarm::NewExternalAddrOfPeer(NewExternalAddrOfPeer { peer_id, addr }) => {
self.kademlia.add_address(&peer_id, addr.clone());
}
FromSwarm::DialFailure(DialFailure {
peer_id: Some(peer_id),
error: DialError::Transport(errors),
..
}) => {
let now = Instant::now();
for (addr, _) in errors {
self.pending_peers
.entry((peer_id, addr.clone()))
.or_insert(now);
}
}
_ => {}
}
self.kademlia.on_swarm_event(event)
}
fn on_connection_handler_event(
&mut self,
peer_id: PeerId,
connection_id: ConnectionId,
event: THandlerOutEvent<Self>,
) {
self.kademlia
.on_connection_handler_event(peer_id, connection_id, event)
}
fn poll(
&mut self,
cx: &mut task::Context<'_>,
) -> task::Poll<ToSwarm<Self::ToSwarm, THandlerInEvent<Self>>> {
loop {
// First priority: return any pending events
if let Some(ev) = self.pending_events.pop_front() {
// Wake if we have more pending events to process
if !self.pending_events.is_empty() {
cx.waker().wake_by_ref();
}
return task::Poll::Ready(ToSwarm::GenerateEvent(ev));
}
// Second priority: poll Kademlia for new events
match self.kademlia.poll(cx) {
task::Poll::Ready(ToSwarm::GenerateEvent(ev)) => {
let (wake, ev) = self.handle_kademlia_event(ev);
// If we have an immediate event to return, return it
if let Some(ev) = ev {
// Wake if requested by handler OR if we have pending events
if wake || !self.pending_events.is_empty() {
cx.waker().wake_by_ref();
}
return task::Poll::Ready(ToSwarm::GenerateEvent(ev));
}
// No immediate event, but if wake was requested or we have pending events,
// continue the loop to process them
if wake || !self.pending_events.is_empty() {
continue;
}
// No immediate event and no wake needed, continue polling Kademlia
// in case it has more events queued
continue;
}
task::Poll::Ready(other_ev) => {
// Non-GenerateEvent from Kademlia (dial events, etc.)
if !self.pending_events.is_empty() {
cx.waker().wake_by_ref();
}
return task::Poll::Ready(
other_ev.map_out(|_| unreachable!("we handled GenerateEvent above")),
);
}
task::Poll::Pending => {
// Kademlia has no more work ready
// Final check: do we have any pending events that were added by the last handler call?
if !self.pending_events.is_empty() {
continue; // Go back to the top to process them
}
// Nothing left to do
return task::Poll::Pending;
}
}
}
}
}