package node import ( "context" "errors" "fmt" "math/rand" "net" "sync" "time" backoffv4 "github.com/cenkalti/backoff/v4" golog "github.com/ipfs/go-log/v2" "github.com/libp2p/go-libp2p" "go.uber.org/zap" "github.com/ethereum/go-ethereum/crypto" "github.com/ethereum/go-ethereum/p2p/enode" "github.com/libp2p/go-libp2p/core/event" "github.com/libp2p/go-libp2p/core/host" "github.com/libp2p/go-libp2p/core/network" "github.com/libp2p/go-libp2p/core/peer" "github.com/libp2p/go-libp2p/core/peerstore" "github.com/libp2p/go-libp2p/core/protocol" "github.com/libp2p/go-libp2p/p2p/discovery/backoff" "github.com/libp2p/go-libp2p/p2p/host/autorelay" "github.com/libp2p/go-libp2p/p2p/host/peerstore/pstoremem" "github.com/libp2p/go-libp2p/p2p/protocol/circuitv2/proto" ws "github.com/libp2p/go-libp2p/p2p/transport/websocket" ma "github.com/multiformats/go-multiaddr" "go.opencensus.io/stats" "github.com/waku-org/go-waku/logging" "github.com/waku-org/go-waku/waku/try" v2 "github.com/waku-org/go-waku/waku/v2" "github.com/waku-org/go-waku/waku/v2/discv5" "github.com/waku-org/go-waku/waku/v2/metrics" "github.com/waku-org/go-waku/waku/v2/peers" "github.com/waku-org/go-waku/waku/v2/protocol/enr" "github.com/waku-org/go-waku/waku/v2/protocol/filter" "github.com/waku-org/go-waku/waku/v2/protocol/legacy_filter" "github.com/waku-org/go-waku/waku/v2/protocol/lightpush" "github.com/waku-org/go-waku/waku/v2/protocol/pb" "github.com/waku-org/go-waku/waku/v2/protocol/peer_exchange" "github.com/waku-org/go-waku/waku/v2/protocol/relay" "github.com/waku-org/go-waku/waku/v2/protocol/store" "github.com/waku-org/go-waku/waku/v2/rendezvous" "github.com/waku-org/go-waku/waku/v2/timesource" "github.com/waku-org/go-waku/waku/v2/utils" ) type Peer struct { ID peer.ID `json:"peerID"` Protocols []protocol.ID `json:"protocols"` Addrs []ma.Multiaddr `json:"addrs"` Connected bool `json:"connected"` } type storeFactory func(w *WakuNode) store.Store type byte32 = [32]byte type IdentityCredential = struct { IDTrapdoor byte32 `json:"idTrapdoor"` IDNullifier byte32 `json:"idNullifier"` IDSecretHash byte32 `json:"idSecretHash"` IDCommitment byte32 `json:"idCommitment"` } type RLNRelay interface { IdentityCredential() (IdentityCredential, error) MembershipIndex() (uint, error) AppendRLNProof(msg *pb.WakuMessage, senderEpochTime time.Time) error Stop() } type WakuNode struct { host host.Host opts *WakuNodeParameters log *zap.Logger timesource timesource.Timesource peerstore peerstore.Peerstore relay Service lightPush Service peerConnector PeerConnectorService discoveryV5 Service peerExchange Service rendezvous Service legacyFilter ReceptorService filterFullnode ReceptorService filterLightnode Service store ReceptorService rlnRelay RLNRelay wakuFlag enr.WakuEnrBitfield circuitRelayNodes chan peer.AddrInfo localNode *enode.LocalNode bcaster relay.Broadcaster connectionNotif ConnectionNotifier protocolEventSub event.Subscription identificationEventSub event.Subscription addressChangesSub event.Subscription enrChangeCh chan struct{} keepAliveMutex sync.Mutex keepAliveFails map[peer.ID]int cancel context.CancelFunc wg *sync.WaitGroup // Channel passed to WakuNode constructor // receiving connection status notifications connStatusChan chan<- ConnStatus storeFactory storeFactory } func defaultStoreFactory(w *WakuNode) store.Store { return store.NewWakuStore(w.opts.messageProvider, w.timesource, w.log) } // New is used to instantiate a WakuNode using a set of WakuNodeOptions func New(opts ...WakuNodeOption) (*WakuNode, error) { var err error params := new(WakuNodeParameters) params.libP2POpts = DefaultLibP2POptions opts = append(DefaultWakuNodeOptions, opts...) for _, opt := range opts { err := opt(params) if err != nil { return nil, err } } if params.logger == nil { params.logger = utils.Logger() //golog.SetPrimaryCore(params.logger.Core()) golog.SetAllLoggers(params.logLevel) } if params.privKey == nil { prvKey, err := crypto.GenerateKey() if err != nil { return nil, err } params.privKey = prvKey } if params.enableWSS { params.libP2POpts = append(params.libP2POpts, libp2p.Transport(ws.New, ws.WithTLSConfig(params.tlsConfig))) } else { // Enable WS transport by default params.libP2POpts = append(params.libP2POpts, libp2p.Transport(ws.New)) } // Setting default host address if none was provided if params.hostAddr == nil { params.hostAddr, err = net.ResolveTCPAddr("tcp", "0.0.0.0:0") if err != nil { return nil, err } err = WithHostAddress(params.hostAddr)(params) if err != nil { return nil, err } } if len(params.multiAddr) > 0 { params.libP2POpts = append(params.libP2POpts, libp2p.ListenAddrs(params.multiAddr...)) } params.libP2POpts = append(params.libP2POpts, params.Identity()) if params.addressFactory != nil { params.libP2POpts = append(params.libP2POpts, libp2p.AddrsFactory(params.addressFactory)) } w := new(WakuNode) w.bcaster = relay.NewBroadcaster(1024) w.opts = params w.log = params.logger.Named("node2") w.wg = &sync.WaitGroup{} w.keepAliveFails = make(map[peer.ID]int) w.wakuFlag = enr.NewWakuEnrBitfield(w.opts.enableLightPush, w.opts.enableLegacyFilter, w.opts.enableStore, w.opts.enableRelay) w.circuitRelayNodes = make(chan peer.AddrInfo) // Setup peerstore wrapper if params.peerstore != nil { w.peerstore = peers.NewWakuPeerstore(params.peerstore) params.libP2POpts = append(params.libP2POpts, libp2p.Peerstore(w.peerstore)) } else { ps, err := pstoremem.NewPeerstore() if err != nil { return nil, err } w.peerstore = peers.NewWakuPeerstore(ps) params.libP2POpts = append(params.libP2POpts, libp2p.Peerstore(w.peerstore)) } // Use circuit relay with nodes received on circuitRelayNodes channel params.libP2POpts = append(params.libP2POpts, libp2p.EnableAutoRelayWithPeerSource( func(ctx context.Context, numPeers int) <-chan peer.AddrInfo { r := make(chan peer.AddrInfo) go func() { defer close(r) for ; numPeers != 0; numPeers-- { select { case v, ok := <-w.circuitRelayNodes: if !ok { return } select { case r <- v: case <-ctx.Done(): return } case <-ctx.Done(): return } } }() return r }, autorelay.WithMinInterval(2*time.Second), )) if params.enableNTP { w.timesource = timesource.NewNTPTimesource(w.opts.ntpURLs, w.log) } else { w.timesource = timesource.NewDefaultClock() } w.localNode, err = enr.NewLocalnode(w.opts.privKey) if err != nil { w.log.Error("creating localnode", zap.Error(err)) } // Setup peer connection strategy cacheSize := 600 rngSrc := rand.NewSource(rand.Int63()) minBackoff, maxBackoff := time.Second*30, time.Hour bkf := backoff.NewExponentialBackoff(minBackoff, maxBackoff, backoff.FullJitter, time.Second, 5.0, 0, rand.New(rngSrc)) w.peerConnector, err = v2.NewPeerConnectionStrategy(cacheSize, w.opts.discoveryMinPeers, network.DialPeerTimeout, bkf, w.log) if err != nil { w.log.Error("creating peer connection strategy", zap.Error(err)) } if w.opts.enableDiscV5 { err := w.mountDiscV5() if err != nil { return nil, err } } w.peerExchange, err = peer_exchange.NewWakuPeerExchange(w.DiscV5(), w.peerConnector, w.log) if err != nil { return nil, err } var rendezvousPoints []peer.ID for _, p := range w.opts.rendezvousNodes { peerID, err := utils.GetPeerID(p) if err != nil { return nil, err } rendezvousPoints = append(rendezvousPoints, peerID) } w.rendezvous = rendezvous.NewRendezvous(w.opts.enableRendezvousServer, w.opts.rendezvousDB, w.opts.enableRendezvous, rendezvousPoints, w.peerConnector, w.log) w.relay = relay.NewWakuRelay(w.bcaster, w.opts.minRelayPeersToPublish, w.timesource, w.log, w.opts.wOpts...) w.legacyFilter = legacy_filter.NewWakuFilter(w.bcaster, w.opts.isLegacyFilterFullnode, w.timesource, w.log, w.opts.legacyFilterOpts...) w.filterFullnode = filter.NewWakuFilterFullnode(w.timesource, w.log, w.opts.filterOpts...) w.filterLightnode = filter.NewWakuFilterLightnode(w.bcaster, w.timesource, w.log) w.lightPush = lightpush.NewWakuLightPush(w.Relay(), w.log) if params.storeFactory != nil { w.storeFactory = params.storeFactory } else { w.storeFactory = defaultStoreFactory } if params.connStatusC != nil { w.connStatusChan = params.connStatusC } return w, nil } func (w *WakuNode) watchMultiaddressChanges(ctx context.Context) { defer w.wg.Done() addrs := w.ListenAddresses() first := make(chan struct{}, 1) first <- struct{}{} for { select { case <-ctx.Done(): return case <-first: w.log.Info("listening", logging.MultiAddrs("multiaddr", addrs...)) w.enrChangeCh <- struct{}{} case <-w.addressChangesSub.Out(): newAddrs := w.ListenAddresses() diff := false if len(addrs) != len(newAddrs) { diff = true } else { for i := range newAddrs { if addrs[i].String() != newAddrs[i].String() { diff = true break } } } if diff { addrs = newAddrs w.log.Info("listening addresses update received", logging.MultiAddrs("multiaddr", addrs...)) _ = w.setupENR(ctx, addrs) w.enrChangeCh <- struct{}{} } } } } // Start initializes all the protocols that were setup in the WakuNode func (w *WakuNode) Start(ctx context.Context) error { connGater := v2.NewConnectionGater(w.log) ctx, cancel := context.WithCancel(ctx) w.cancel = cancel w.opts.libP2POpts = append(w.opts.libP2POpts, libp2p.ConnectionGater(connGater)) host, err := libp2p.New(w.opts.libP2POpts...) if err != nil { return err } host.Network().Notify(&network.NotifyBundle{ DisconnectedF: func(net network.Network, conn network.Conn) { go connGater.NotifyDisconnect(conn.RemoteMultiaddr()) }, }) w.host = host if w.protocolEventSub, err = host.EventBus().Subscribe(new(event.EvtPeerProtocolsUpdated)); err != nil { return err } if w.identificationEventSub, err = host.EventBus().Subscribe(new(event.EvtPeerIdentificationCompleted)); err != nil { return err } if w.addressChangesSub, err = host.EventBus().Subscribe(new(event.EvtLocalAddressesUpdated)); err != nil { return err } w.connectionNotif = NewConnectionNotifier(ctx, w.host, w.opts.connNotifCh, w.log) w.host.Network().Notify(w.connectionNotif) w.enrChangeCh = make(chan struct{}, 10) w.wg.Add(4) go w.connectednessListener(ctx) go w.watchMultiaddressChanges(ctx) go w.watchENRChanges(ctx) go w.findRelayNodes(ctx) err = w.bcaster.Start(ctx) if err != nil { return err } if w.opts.keepAliveInterval > time.Duration(0) { w.wg.Add(1) go w.startKeepAlive(ctx, w.opts.keepAliveInterval) } w.peerConnector.SetHost(host) err = w.peerConnector.Start(ctx) if err != nil { return err } if w.opts.enableNTP { err := w.timesource.Start(ctx) if err != nil { return err } } w.relay.SetHost(host) if w.opts.enableRelay { err := w.relay.Start(ctx) if err != nil { return err } if !w.opts.noDefaultWakuTopic { sub, err := w.Relay().Subscribe(ctx) if err != nil { return err } sub.Unsubscribe() } } w.store = w.storeFactory(w) w.store.SetHost(host) if w.opts.enableStore { sub := w.bcaster.RegisterForAll() err := w.startStore(ctx, sub) if err != nil { return err } w.log.Info("Subscribing store to broadcaster") } w.lightPush.SetHost(host) if w.opts.enableLightPush { if err := w.lightPush.Start(ctx); err != nil { return err } } w.legacyFilter.SetHost(host) if w.opts.enableLegacyFilter { sub := w.bcaster.RegisterForAll() err := w.legacyFilter.Start(ctx, sub) if err != nil { return err } w.log.Info("Subscribing filter to broadcaster") } w.filterFullnode.SetHost(host) if w.opts.enableFilterFullNode { sub := w.bcaster.RegisterForAll() err := w.filterFullnode.Start(ctx, sub) if err != nil { return err } w.log.Info("Subscribing filterV2 to broadcaster") } w.filterLightnode.SetHost(host) if w.opts.enableFilterLightNode { err := w.filterLightnode.Start(ctx) if err != nil { return err } } err = w.setupENR(ctx, w.ListenAddresses()) if err != nil { return err } w.peerExchange.SetHost(host) if w.opts.enablePeerExchange { err := w.peerExchange.Start(ctx) if err != nil { return err } } w.rendezvous.SetHost(host) if w.opts.enableRendezvousServer || w.opts.enableRendezvous { err := w.rendezvous.Start(ctx) if err != nil { return err } } if w.opts.enableRLN { err = w.mountRlnRelay(ctx) if err != nil { return err } } return nil } // Stop stops the WakuNode and closess all connections to the host func (w *WakuNode) Stop() { if w.cancel == nil { return } w.bcaster.Stop() defer w.connectionNotif.Close() defer w.protocolEventSub.Close() defer w.identificationEventSub.Close() defer w.addressChangesSub.Close() if w.opts.enableRendezvousServer || w.opts.enableRendezvous { w.rendezvous.Stop() } w.relay.Stop() w.lightPush.Stop() w.store.Stop() w.legacyFilter.Stop() w.filterFullnode.Stop() if w.opts.enableDiscV5 { w.discoveryV5.Stop() } w.peerExchange.Stop() w.peerConnector.Stop() _ = w.stopRlnRelay() w.timesource.Stop() w.host.Close() w.cancel() w.wg.Wait() close(w.enrChangeCh) w.cancel = nil } // Host returns the libp2p Host used by the WakuNode func (w *WakuNode) Host() host.Host { return w.host } // ID returns the base58 encoded ID from the host func (w *WakuNode) ID() string { return w.host.ID().Pretty() } func (w *WakuNode) watchENRChanges(ctx context.Context) { defer w.wg.Done() var prevNodeVal string for { select { case <-ctx.Done(): return case <-w.enrChangeCh: if w.localNode != nil { currNodeVal := w.localNode.Node().String() if prevNodeVal != currNodeVal { if prevNodeVal == "" { w.log.Info("enr record", logging.ENode("enr", w.localNode.Node())) } else { w.log.Info("new enr record", logging.ENode("enr", w.localNode.Node())) } prevNodeVal = currNodeVal } } } } } // ListenAddresses returns all the multiaddresses used by the host func (w *WakuNode) ListenAddresses() []ma.Multiaddr { hostInfo, _ := ma.NewMultiaddr(fmt.Sprintf("/p2p/%s", w.host.ID().Pretty())) var result []ma.Multiaddr for _, addr := range w.host.Addrs() { result = append(result, addr.Encapsulate(hostInfo)) } return result } // ENR returns the ENR address of the node func (w *WakuNode) ENR() *enode.Node { return w.localNode.Node() } // Timesource returns the timesource used by this node to obtain the current wall time // Depending on the configuration it will be the local time or a ntp syncd time func (w *WakuNode) Timesource() timesource.Timesource { return w.timesource } // Relay is used to access any operation related to Waku Relay protocol func (w *WakuNode) Relay() *relay.WakuRelay { if result, ok := w.relay.(*relay.WakuRelay); ok { return result } return nil } // Store is used to access any operation related to Waku Store protocol func (w *WakuNode) Store() store.Store { return w.store.(store.Store) } // LegacyFilter is used to access any operation related to Waku LegacyFilter protocol func (w *WakuNode) LegacyFilter() *legacy_filter.WakuFilter { if result, ok := w.legacyFilter.(*legacy_filter.WakuFilter); ok { return result } return nil } // FilterLightnode is used to access any operation related to Waku Filter protocol Full node feature func (w *WakuNode) FilterFullnode() *filter.WakuFilterFullNode { if result, ok := w.filterFullnode.(*filter.WakuFilterFullNode); ok { return result } return nil } // FilterFullnode is used to access any operation related to Waku Filter protocol Light node feature func (w *WakuNode) FilterLightnode() *filter.WakuFilterLightnode { if result, ok := w.filterLightnode.(*filter.WakuFilterLightnode); ok { return result } return nil } // Lightpush is used to access any operation related to Waku Lightpush protocol func (w *WakuNode) Lightpush() *lightpush.WakuLightPush { if result, ok := w.lightPush.(*lightpush.WakuLightPush); ok { return result } return nil } // DiscV5 is used to access any operation related to DiscoveryV5 func (w *WakuNode) DiscV5() *discv5.DiscoveryV5 { if result, ok := w.discoveryV5.(*discv5.DiscoveryV5); ok { return result } return nil } // PeerExchange is used to access any operation related to Peer Exchange func (w *WakuNode) PeerExchange() *peer_exchange.WakuPeerExchange { if result, ok := w.peerExchange.(*peer_exchange.WakuPeerExchange); ok { return result } return nil } // Broadcaster is used to access the message broadcaster that is used to push // messages to different protocols func (w *WakuNode) Broadcaster() relay.Broadcaster { return w.bcaster } // Publish will attempt to publish a message via WakuRelay if there are enough // peers available, otherwise it will attempt to publish via Lightpush protocol func (w *WakuNode) Publish(ctx context.Context, msg *pb.WakuMessage) error { if !w.opts.enableLightPush && !w.opts.enableRelay { return errors.New("cannot publish message, relay and lightpush are disabled") } hash := msg.Hash(relay.DefaultWakuTopic) err := try.Do(func(attempt int) (bool, error) { var err error relay := w.Relay() lightpush := w.Lightpush() if relay == nil || !relay.EnoughPeersToPublish() { w.log.Debug("publishing message via lightpush", logging.HexBytes("hash", hash)) _, err = lightpush.Publish(ctx, msg) } else { w.log.Debug("publishing message via relay", logging.HexBytes("hash", hash)) _, err = relay.Publish(ctx, msg) } return attempt < maxPublishAttempt, err }) return err } func (w *WakuNode) mountDiscV5() error { discV5Options := []discv5.DiscoveryV5Option{ discv5.WithBootnodes(w.opts.discV5bootnodes), discv5.WithUDPPort(w.opts.udpPort), discv5.WithAutoUpdate(w.opts.discV5autoUpdate), } if w.opts.advertiseAddrs != nil { discV5Options = append(discV5Options, discv5.WithAdvertiseAddr(w.opts.advertiseAddrs)) } var err error w.discoveryV5, err = discv5.NewDiscoveryV5(w.opts.privKey, w.localNode, w.peerConnector, w.log, discV5Options...) return err } func (w *WakuNode) startStore(ctx context.Context, sub relay.Subscription) error { err := w.store.Start(ctx, sub) if err != nil { w.log.Error("starting store", zap.Error(err)) return err } if len(w.opts.resumeNodes) != 0 { // TODO: extract this to a function and run it when you go offline // TODO: determine if a store is listening to a topic var peerIDs []peer.ID for _, n := range w.opts.resumeNodes { pID, err := w.AddPeer(n, peers.Static, store.StoreID_v20beta4) if err != nil { w.log.Warn("adding peer to peerstore", logging.MultiAddrs("peer", n), zap.Error(err)) } peerIDs = append(peerIDs, pID) } if !w.opts.noDefaultWakuTopic { w.wg.Add(1) go func() { defer w.wg.Done() ctxWithTimeout, ctxCancel := context.WithTimeout(ctx, 20*time.Second) defer ctxCancel() if _, err := w.store.(store.Store).Resume(ctxWithTimeout, string(relay.DefaultWakuTopic), peerIDs); err != nil { w.log.Error("Could not resume history", zap.Error(err)) time.Sleep(10 * time.Second) } }() } } return nil } func (w *WakuNode) addPeer(info *peer.AddrInfo, origin peers.Origin, protocols ...protocol.ID) error { w.log.Info("adding peer to peerstore", logging.HostID("peer", info.ID)) err := w.host.Peerstore().(peers.WakuPeerstore).SetOrigin(info.ID, origin) if err != nil { return err } w.host.Peerstore().AddAddrs(info.ID, info.Addrs, peerstore.AddressTTL) err = w.host.Peerstore().AddProtocols(info.ID, protocols...) if err != nil { return err } return nil } // AddPeer is used to add a peer and the protocols it support to the node peerstore func (w *WakuNode) AddPeer(address ma.Multiaddr, origin peers.Origin, protocols ...protocol.ID) (peer.ID, error) { info, err := peer.AddrInfoFromP2pAddr(address) if err != nil { return "", err } return info.ID, w.addPeer(info, origin, protocols...) } // DialPeerWithMultiAddress is used to connect to a peer using a multiaddress func (w *WakuNode) DialPeerWithMultiAddress(ctx context.Context, address ma.Multiaddr) error { info, err := peer.AddrInfoFromP2pAddr(address) if err != nil { return err } return w.connect(ctx, *info) } // DialPeer is used to connect to a peer using a string containing a multiaddress func (w *WakuNode) DialPeer(ctx context.Context, address string) error { p, err := ma.NewMultiaddr(address) if err != nil { return err } info, err := peer.AddrInfoFromP2pAddr(p) if err != nil { return err } return w.connect(ctx, *info) } // DialPeerWithInfo is used to connect to a peer using its address information func (w *WakuNode) DialPeerWithInfo(ctx context.Context, peerInfo peer.AddrInfo) error { return w.connect(ctx, peerInfo) } func (w *WakuNode) connect(ctx context.Context, info peer.AddrInfo) error { err := w.host.Connect(ctx, info) if err != nil { w.host.Peerstore().(peers.WakuPeerstore).AddConnFailure(info) return err } w.host.Peerstore().(peers.WakuPeerstore).ResetConnFailures(info) stats.Record(ctx, metrics.Dials.M(1)) return nil } // DialPeerByID is used to connect to an already known peer func (w *WakuNode) DialPeerByID(ctx context.Context, peerID peer.ID) error { info := w.host.Peerstore().PeerInfo(peerID) return w.connect(ctx, info) } // ClosePeerByAddress is used to disconnect from a peer using its multiaddress func (w *WakuNode) ClosePeerByAddress(address string) error { p, err := ma.NewMultiaddr(address) if err != nil { return err } // Extract the peer ID from the multiaddr. info, err := peer.AddrInfoFromP2pAddr(p) if err != nil { return err } return w.ClosePeerById(info.ID) } // ClosePeerById is used to close a connection to a peer func (w *WakuNode) ClosePeerById(id peer.ID) error { err := w.host.Network().ClosePeer(id) if err != nil { return err } return nil } // PeerCount return the number of connected peers func (w *WakuNode) PeerCount() int { return len(w.host.Network().Peers()) } // PeerStats returns a list of peers and the protocols supported by them func (w *WakuNode) PeerStats() PeerStats { p := make(PeerStats) for _, peerID := range w.host.Network().Peers() { protocols, err := w.host.Peerstore().GetProtocols(peerID) if err != nil { continue } p[peerID] = protocols } return p } // Set the bootnodes on discv5 func (w *WakuNode) SetDiscV5Bootnodes(nodes []*enode.Node) error { w.opts.discV5bootnodes = nodes return w.DiscV5().SetBootnodes(nodes) } // Peers return the list of peers, addresses, protocols supported and connection status func (w *WakuNode) Peers() ([]*Peer, error) { var peers []*Peer for _, peerId := range w.host.Peerstore().Peers() { connected := w.host.Network().Connectedness(peerId) == network.Connected protocols, err := w.host.Peerstore().GetProtocols(peerId) if err != nil { return nil, err } addrs := w.host.Peerstore().Addrs(peerId) peers = append(peers, &Peer{ ID: peerId, Protocols: protocols, Connected: connected, Addrs: addrs, }) } return peers, nil } func (w *WakuNode) findRelayNodes(ctx context.Context) { defer w.wg.Done() // Feed peers more often right after the bootstrap, then backoff bo := backoffv4.NewExponentialBackOff() bo.InitialInterval = 15 * time.Second bo.Multiplier = 3 bo.MaxInterval = 1 * time.Hour bo.MaxElapsedTime = 0 // never stop t := backoffv4.NewTicker(bo) defer t.Stop() for { select { case <-t.C: case <-ctx.Done(): return } peers, err := w.Peers() if err != nil { w.log.Error("failed to fetch peers", zap.Error(err)) continue } // Shuffle peers rand.Seed(time.Now().UnixNano()) rand.Shuffle(len(peers), func(i, j int) { peers[i], peers[j] = peers[j], peers[i] }) for _, p := range peers { info := w.Host().Peerstore().PeerInfo(p.ID) supportedProtocols, err := w.Host().Peerstore().SupportsProtocols(p.ID, proto.ProtoIDv2Hop) if err != nil { w.log.Error("could not check supported protocols", zap.Error(err)) continue } if len(supportedProtocols) == 0 { continue } select { case <-ctx.Done(): w.log.Debug("context done, auto-relay has enough peers") return case w.circuitRelayNodes <- info: w.log.Debug("published auto-relay peer info", zap.Any("peer-id", p.ID)) } } } }