libp2p/dist/src/peer-routing.js

JavaScript implementation of libp2p, a modular peer to peer network stack

import { NotFoundError } from '@libp2p/interface';
import { createScalableCuckooFilter } from '@libp2p/utils/filters';
import merge from 'it-merge';
import parallel from 'it-parallel';
import { toString as uint8ArrayToString } from 'uint8arrays/to-string';
import { NoPeerRoutersError, QueriedForSelfError } from './errors.js';
export class DefaultPeerRouting {
    log;
    peerId;
    peerStore;
    routers;
    constructor(components, init = {}) {
        this.log = components.logger.forComponent('libp2p:peer-routing');
        this.peerId = components.peerId;
        this.peerStore = components.peerStore;
        this.routers = init.routers ?? [];
        this.findPeer = components.metrics?.traceFunction('libp2p.peerRouting.findPeer', this.findPeer.bind(this), {
            optionsIndex: 1,
            getAttributesFromArgs: ([peer], attrs) => {
                return {
                    ...attrs,
                    peer: peer.toString()
                };
            }
        }) ?? this.findPeer;
        this.getClosestPeers = components.metrics?.traceFunction('libp2p.peerRouting.getClosestPeers', this.getClosestPeers.bind(this), {
            optionsIndex: 1,
            getAttributesFromArgs: ([key], attrs) => {
                return {
                    ...attrs,
                    key: uint8ArrayToString(key, 'base36')
                };
            },
            getAttributesFromYieldedValue: (value, attrs) => {
                return {
                    ...attrs,
                    peers: [...(Array.isArray(attrs.peers) ? attrs.peers : []), value.id.toString()]
                };
            }
        }) ?? this.getClosestPeers;
    }
    [Symbol.toStringTag] = '@libp2p/peer-routing';
    /**
     * Iterates over all peer routers in parallel to find the given peer
     */
    async findPeer(id, options) {
        if (this.routers.length === 0) {
            throw new NoPeerRoutersError('No peer routers available');
        }
        if (id.toString() === this.peerId.toString()) {
            throw new QueriedForSelfError('Should not try to find self');
        }
        const self = this;
        const source = merge(...this.routers
            .filter(router => router.findPeer instanceof Function)
            .map(router => (async function* () {
            try {
                yield await router.findPeer(id, options);
            }
            catch (err) {
                self.log.error(err);
            }
        })()));
        for await (const peer of source) {
            if (peer == null) {
                continue;
            }
            // store the addresses for the peer if found
            if (peer.multiaddrs.length > 0) {
                await this.peerStore.merge(peer.id, {
                    multiaddrs: peer.multiaddrs
                }, options);
            }
            return peer;
        }
        throw new NotFoundError();
    }
    /**
     * Attempt to find the closest peers on the network to the given key
     */
    async *getClosestPeers(key, options = {}) {
        if (this.routers.length === 0) {
            throw new NoPeerRoutersError('No peer routers available');
        }
        const self = this;
        const seen = createScalableCuckooFilter(1024);
        for await (const peer of parallel(async function* () {
            const source = merge(...self.routers
                .filter(router => router.getClosestPeers instanceof Function)
                .map(router => router.getClosestPeers(key, options)));
            for await (let peer of source) {
                yield async () => {
                    // find multiaddrs if they are missing
                    if (peer.multiaddrs.length === 0) {
                        try {
                            peer = await self.findPeer(peer.id, {
                                ...options,
                                useCache: false
                            });
                        }
                        catch (err) {
                            self.log.error('could not find peer multiaddrs', err);
                            return;
                        }
                    }
                    return peer;
                };
            }
        }())) {
            if (peer == null) {
                continue;
            }
            // store the addresses for the peer if found
            if (peer.multiaddrs.length > 0) {
                await this.peerStore.merge(peer.id, {
                    multiaddrs: peer.multiaddrs
                }, options);
            }
            // deduplicate peers
            if (seen.has(peer.id.toMultihash().bytes)) {
                continue;
            }
            seen.add(peer.id.toMultihash().bytes);
            yield peer;
        }
    }
}
//# sourceMappingURL=peer-routing.js.map