Swarm Bootstrap Nodes (#201)

# Description

Adds bootstrap nodes in settings that will be connected to on node
startup.

## Link to issue

Please add a link to any relevant issues/tickets.

## Type of change

- [x] New feature (non-breaking change that adds functionality)

Please delete options that are not relevant.

## Test plan (required)

Parsing testing is added with the other settings test. Tests actually
dialing nodes will be added in a different PR since this is a perquisite
to gossip/receipt testing anyways.

---------

Signed-off-by: Melanie Riise <[email protected]>

homestar-runtime/fixtures/settings.toml

@@ -6,3 +6,4 @@ process_collector_interval = 10
 [node.network]
 events_buffer_len = 1000
 websocket_port = 9999
+node_addresses = ["/ip4/127.0.0.1/tcp/9998/ws"]

homestar-runtime/src/event_handler.rs

@@ -12,7 +12,10 @@ use crate::{
 use anyhow::Result;
 use async_trait::async_trait;
 use fnv::FnvHashMap;
-use libp2p::{futures::StreamExt, kad::QueryId, request_response::RequestId, swarm::Swarm};
+use libp2p::{
+    core::ConnectedPoint, futures::StreamExt, kad::QueryId, request_response::RequestId,
+    swarm::Swarm, PeerId,
+};
 use std::{sync::Arc, time::Duration};
 use swarm_event::ResponseEvent;
 use tokio::{select, sync::mpsc};
@@ -54,6 +57,7 @@ pub(crate) struct EventHandler<DB: Database> {
     sender: Arc<mpsc::Sender<Event>>,
     receiver: mpsc::Receiver<Event>,
     query_senders: FnvHashMap<QueryId, (RequestResponseKey, P2PSender)>,
+    connected_peers: FnvHashMap<PeerId, ConnectedPoint>,
     request_response_senders: FnvHashMap<RequestId, (RequestResponseKey, P2PSender)>,
     ws_msg_sender: ws::Notifier,
 }
@@ -70,6 +74,7 @@ pub(crate) struct EventHandler<DB: Database> {
     sender: Arc<mpsc::Sender<Event>>,
     receiver: mpsc::Receiver<Event>,
     query_senders: FnvHashMap<QueryId, (RequestResponseKey, P2PSender)>,
+    connected_peers: FnvHashMap<PeerId, ConnectedPoint>,
     request_response_senders: FnvHashMap<RequestId, (RequestResponseKey, P2PSender)>,
 }
 
@@ -100,6 +105,7 @@ where
             receiver,
             query_senders: FnvHashMap::default(),
             request_response_senders: FnvHashMap::default(),
+            connected_peers: FnvHashMap::default(),
             ws_msg_sender,
         }
     }
@@ -117,6 +123,7 @@ where
             sender: Arc::new(sender),
             receiver,
             query_senders: FnvHashMap::default(),
+            connected_peers: FnvHashMap::default(),
             request_response_senders: FnvHashMap::default(),
         }
     }

homestar-runtime/src/event_handler/swarm_event.rs

@@ -93,6 +93,8 @@ async fn handle_swarm_event<THandlerErr: fmt::Debug + Send, DB: Database>(
     event_handler: &mut EventHandler<DB>,
 ) {
     match event {
+        // TODO: add identify for adding compatable kademlia nodes.
+        // TODO: use kademlia to discover new gossip nodes.
         SwarmEvent::Behaviour(ComposedEvent::Gossipsub(gossip_event)) => match *gossip_event {
             gossipsub::Event::Message {
                 message,
@@ -370,6 +372,16 @@ async fn handle_swarm_event<THandlerErr: fmt::Debug + Send, DB: Database>(
             );
         }
         SwarmEvent::IncomingConnection { .. } => {}
+        SwarmEvent::ConnectionEstablished {
+            peer_id, endpoint, ..
+        } => {
+            // add peer to connected peers list
+            event_handler.connected_peers.insert(peer_id, endpoint);
+        }
+        SwarmEvent::ConnectionClosed { peer_id, cause, .. } => {
+            info!("peer connection closed {peer_id}, cause: {cause:?}");
+            event_handler.connected_peers.remove_entry(&peer_id);
+        }
         _ => {}
     }
 }

homestar-runtime/src/network/swarm.rs

@@ -10,13 +10,16 @@ use libp2p::{
     core::upgrade,
     gossipsub::{self, MessageId, SubscriptionError, TopicHash},
     kad::{record::store::MemoryStore, Kademlia, KademliaEvent},
-    mdns, noise,
+    mdns,
+    multiaddr::Protocol,
+    noise,
     request_response::{self, ProtocolSupport},
     swarm::{NetworkBehaviour, Swarm, SwarmBuilder},
     tcp, yamux, StreamProtocol, Transport,
 };
 use serde::{Deserialize, Serialize};
 use std::fmt;
+use tracing::{info, warn};
 
 /// Build a new [Swarm] with a given transport and a tokio executor.
 pub(crate) async fn new(settings: &settings::Node) -> Result<Swarm<ComposedBehaviour>> {
@@ -27,6 +30,7 @@ pub(crate) async fn new(settings: &settings::Node) -> Result<Swarm<ComposedBehav
         .with_context(|| "Failed to generate/import keypair for libp2p".to_string())?;
 
     let peer_id = keypair.public().to_peer_id();
+    info!(peer_id=?peer_id.to_string(), "local peer ID generated");
 
     let transport = tcp::tokio::Transport::new(tcp::Config::default().nodelay(true))
         .upgrade(upgrade::Version::V1Lazy)
@@ -60,15 +64,43 @@ pub(crate) async fn new(settings: &settings::Node) -> Result<Swarm<ComposedBehav
     )
     .build();
 
+    startup(&mut swarm, &settings.network)?;
+
+    Ok(swarm)
+}
+
+fn startup(swarm: &mut Swarm<ComposedBehaviour>, settings: &settings::Network) -> Result<()> {
     // Listen-on given address
-    swarm.listen_on(settings.network.listen_address.to_string().parse()?)?;
+    swarm.listen_on(settings.listen_address.to_string().parse()?)?;
+
+    // Dial nodes specified in settings. Failure here shouldn't halt node startup.
+    for addr in &settings.node_addresses {
+        match swarm.dial(addr.clone()) {
+            Ok(_) => info!(addr=?addr, "successfully dialed configured node"),
+            // log dial failure and continue
+            Err(e) => warn!(err=?e, "failed to dial configured node"),
+        }
 
-    // subscribe to `receipts` topic
+        // add node to kademlia routing table
+        if let Some(Protocol::P2p(peer_id)) =
+            addr.iter().find(|proto| matches!(proto, Protocol::P2p(_)))
+        {
+            info!(addr=?addr, "added configured node to kademlia routing table");
+            swarm
+                .behaviour_mut()
+                .kademlia
+                .add_address(&peer_id, addr.clone());
+        } else {
+            warn!(addr=?addr, err="configured node address did not include a peer ID", "node not added to kademlia routing table")
+        }
+    }
+
+    // join `receipts` topic
     swarm
         .behaviour_mut()
         .gossip_subscribe(pubsub::RECEIPTS_TOPIC)?;
 
-    Ok(swarm)
+    Ok(())
 }
 
 /// Key data structure for [request_response::Event] messages.

homestar-runtime/src/settings.rs

@@ -121,6 +121,9 @@ pub struct Network {
     pub(crate) workflow_quorum: usize,
     /// Pubkey setup configuration
     pub(crate) keypair_config: PubkeyConfig,
+    /// Multiaddrs of the trusted nodes to connect to on startup.
+    #[serde_as(as = "Vec<serde_with::DisplayFromStr>")]
+    pub(crate) node_addresses: Vec<libp2p::Multiaddr>,
 }
 
 /// Database-related settings for a homestar node.
@@ -172,6 +175,7 @@ impl Default for Network {
             websocket_capacity: 100,
             workflow_quorum: 3,
             keypair_config: PubkeyConfig::Random,
+            node_addresses: Vec::new(),
         }
     }
 }
@@ -265,8 +269,9 @@ mod test {
         default_modded_settings.network.websocket_port = 9999;
         default_modded_settings.gc_interval = Duration::from_secs(1800);
         default_modded_settings.shutdown_timeout = Duration::from_secs(20);
-
-        assert_eq!(settings.node, default_modded_settings);
+        default_modded_settings.network.node_addresses =
+            vec!["/ip4/127.0.0.1/tcp/9998/ws".to_string().try_into().unwrap()];
+        assert_eq!(settings.node(), &default_modded_settings);
     }
 
     #[test]

homestar-runtime/tests/test_node1/config/settings.toml

@@ -0,0 +1,11 @@
+[monitoring]
+process_collector_interval = 10
+
+[node]
+
+[node.network]
+websocket_port = 9090
+trusted_node_addresses = ["/ip4/127.0.0.1/tcp/9091/ws"]
+
+[node.network.keypair_config]
+existing = { key_type = "ed25519", path = "../../fixtures/__testkey_ed25519.pem" }

homestar-runtime/tests/test_node2/config/settings.toml

@@ -0,0 +1,10 @@
+[monitoring]
+process_collector_interval = 10
+
+[node]
+
+[node.network]
+websocket_port = 9091
+node_addresses = [
+    "/ip4/127.0.0.1/tcp/9090/ws/p2p/12D3KooWDpJ7As7BWAwRMfu1VU2WCqNjvq387JEYKDBj4kx6nXTN",
+]