use async_std::io;
use futures::{
prelude::{stream::StreamExt, *},
select,
};
use libp2p::{
floodsub::{self, Floodsub, FloodsubEvent},
identity, mdns,
swarm::{NetworkBehaviour, SwarmEvent},
Multiaddr, PeerId, Swarm,
};
use std::error::Error;
#[async_std::main]
async fn main() -> Result<(), Box<dyn Error>> {
env_logger::init();
let local_key = identity::Keypair::generate_ed25519();
let local_peer_id = PeerId::from(local_key.public());
println!("Local peer id: {local_peer_id:?}");
let transport = libp2p::development_transport(local_key).await?;
let floodsub_topic = floodsub::Topic::new("chat");
#[derive(NetworkBehaviour)]
#[behaviour(out_event = "OutEvent")]
struct MyBehaviour {
floodsub: Floodsub,
mdns: mdns::async_io::Behaviour,
}
#[allow(clippy::large_enum_variant)]
#[derive(Debug)]
enum OutEvent {
Floodsub(FloodsubEvent),
Mdns(mdns::Event),
}
impl From<mdns::Event> for OutEvent {
fn from(v: mdns::Event) -> Self {
Self::Mdns(v)
}
}
impl From<FloodsubEvent> for OutEvent {
fn from(v: FloodsubEvent) -> Self {
Self::Floodsub(v)
}
}
let mut swarm = {
let mdns = mdns::async_io::Behaviour::new(mdns::Config::default())?;
let mut behaviour = MyBehaviour {
floodsub: Floodsub::new(local_peer_id),
mdns,
};
behaviour.floodsub.subscribe(floodsub_topic.clone());
Swarm::with_threadpool_executor(transport, behaviour, local_peer_id)
};
if let Some(to_dial) = std::env::args().nth(1) {
let addr: Multiaddr = to_dial.parse()?;
swarm.dial(addr)?;
println!("Dialed {to_dial:?}")
}
let mut stdin = io::BufReader::new(io::stdin()).lines().fuse();
swarm.listen_on("/ip4/0.0.0.0/tcp/0".parse()?)?;
loop {
select! {
line = stdin.select_next_some() => swarm
.behaviour_mut()
.floodsub
.publish(floodsub_topic.clone(), line.expect("Stdin not to close").as_bytes()),
event = swarm.select_next_some() => match event {
SwarmEvent::NewListenAddr { address, .. } => {
println!("Listening on {address:?}");
}
SwarmEvent::Behaviour(OutEvent::Floodsub(
FloodsubEvent::Message(message)
)) => {
println!(
"Received: '{:?}' from {:?}",
String::from_utf8_lossy(&message.data),
message.source
);
}
SwarmEvent::Behaviour(OutEvent::Mdns(
mdns::Event::Discovered(list)
)) => {
for (peer, _) in list {
swarm
.behaviour_mut()
.floodsub
.add_node_to_partial_view(peer);
}
}
SwarmEvent::Behaviour(OutEvent::Mdns(mdns::Event::Expired(
list
))) => {
for (peer, _) in list {
if !swarm.behaviour_mut().mdns.has_node(&peer) {
swarm
.behaviour_mut()
.floodsub
.remove_node_from_partial_view(&peer);
}
}
},
_ => {}
}
}
}
}