feat: custom dialer addr sorter (#792)

* feat: custom dialer addr sorter

* chore: use libp2p utils sorter via addressBook getMultiaddrsForPeer

* chore: use new libp2p utils

* chore: apply suggestions from code review

Co-authored-by: Jacob Heun <jacobheun@gmail.com>

Co-authored-by: Jacob Heun <jacobheun@gmail.com>

src/circuit/auto-relay.js

@@ -4,8 +4,6 @@ const debug = require('debug')
 const log = debug('libp2p:auto-relay')
 log.error = debug('libp2p:auto-relay:error')
 
-const isPrivate = require('libp2p-utils/src/multiaddr/is-private')
-
 const uint8ArrayFromString = require('uint8arrays/from-string')
 const uint8ArrayToString = require('uint8arrays/to-string')
 const multiaddr = require('multiaddr')
@@ -36,6 +34,7 @@ class AutoRelay {
     this._peerStore = libp2p.peerStore
     this._connectionManager = libp2p.connectionManager
     this._transportManager = libp2p.transportManager
+    this._addressSorter = libp2p.dialer.addressSorter
 
     this.maxListeners = maxListeners
 
@@ -129,37 +128,19 @@ class AutoRelay {
       return
     }
 
-    // Create relay listen addr
-    let listenAddr, remoteMultiaddr, remoteAddrs
+    // Get peer known addresses and sort them per public addresses first
+    const remoteAddrs = this._peerStore.addressBook.getMultiaddrsForPeer(
+      connection.remotePeer, this._addressSorter
+    )
 
-    try {
-      // Get peer known addresses and sort them per public addresses first
-      remoteAddrs = this._peerStore.addressBook.get(connection.remotePeer)
-      // TODO: This sort should be customizable in the config (dialer addr sort)
-      remoteAddrs.sort(multiaddrsCompareFunction)
-
-      remoteMultiaddr = remoteAddrs.find(a => a.isCertified).multiaddr // Get first announced address certified
-      // TODO: HOP Relays should avoid advertising private addresses!
-    } catch (_) {
-      log.error(`${id} does not have announced certified multiaddrs`)
-
-      // Attempt first if existing
-      if (!remoteAddrs || !remoteAddrs.length) {
-        return
-      }
-
-      remoteMultiaddr = remoteAddrs[0].multiaddr
+    if (!remoteAddrs || !remoteAddrs.length) {
+      return
     }
 
-    if (!remoteMultiaddr.protoNames().includes('p2p')) {
-      listenAddr = `${remoteMultiaddr.toString()}/p2p/${connection.remotePeer.toB58String()}/p2p-circuit`
-    } else {
-      listenAddr = `${remoteMultiaddr.toString()}/p2p-circuit`
-    }
-
-    // Attempt to listen on relay
+    const listenAddr = `${remoteAddrs[0].toString()}/p2p-circuit`
     this._listenRelays.add(id)
 
+    // Attempt to listen on relay
     try {
       await this._transportManager.listen([multiaddr(listenAddr)])
       // Announce multiaddrs will update on listen success by TransportManager event being triggered
@@ -269,24 +250,4 @@ class AutoRelay {
   }
 }
 
-/**
- * Compare function for array.sort().
- * This sort aims to move the private adresses to the end of the array.
- *
- * @param {Address} a
- * @param {Address} b
- * @returns {number}
- */
-function multiaddrsCompareFunction (a, b) {
-  const isAPrivate = isPrivate(a.multiaddr)
-  const isBPrivate = isPrivate(b.multiaddr)
-
-  if (isAPrivate && !isBPrivate) {
-    return 1
-  } else if (!isAPrivate && isBPrivate) {
-    return -1
-  }
-  return 0
-}
-
 module.exports = AutoRelay

src/config.js

@@ -7,6 +7,7 @@ const Constants = require('./constants')
 const { AGENT_VERSION } = require('./identify/consts')
 const RelayConstants = require('./circuit/constants')
 
+const { publicAddressesFirst } = require('libp2p-utils/src/address-sort')
 const { FaultTolerance } = require('./transport-manager')
 
 const DefaultConfig = {
@@ -27,7 +28,8 @@ const DefaultConfig = {
     dialTimeout: Constants.DIAL_TIMEOUT,
     resolvers: {
       dnsaddr: dnsaddrResolver
-    }
+    },
+    addressSorter: publicAddressesFirst
   },
   host: {
     agentVersion: AGENT_VERSION

src/dialer/index.js

@@ -9,6 +9,7 @@ const log = debug('libp2p:dialer')
 log.error = debug('libp2p:dialer:error')
 
 const { DialRequest } = require('./dial-request')
+const { publicAddressesFirst } = require('libp2p-utils/src/address-sort')
 const getPeer = require('../get-peer')
 
 const { codes } = require('../errors')
@@ -24,6 +25,7 @@ class Dialer {
    * @param {object} options
    * @param {TransportManager} options.transportManager
    * @param {Peerstore} options.peerStore
+   * @param {(addresses: Array<Address) => Array<Address>} [options.addressSorter = publicAddressesFirst] - Sort the known addresses of a peer before trying to dial.
    * @param {number} [options.concurrency = MAX_PARALLEL_DIALS] - Number of max concurrent dials.
    * @param {number} [options.perPeerLimit = MAX_PER_PEER_DIALS] - Number of max concurrent dials per peer.
    * @param {number} [options.timeout = DIAL_TIMEOUT] - How long a dial attempt is allowed to take.
@@ -32,6 +34,7 @@ class Dialer {
   constructor ({
     transportManager,
     peerStore,
+    addressSorter = publicAddressesFirst,
     concurrency = MAX_PARALLEL_DIALS,
     timeout = DIAL_TIMEOUT,
     perPeerLimit = MAX_PER_PEER_DIALS,
@@ -39,6 +42,7 @@ class Dialer {
   }) {
     this.transportManager = transportManager
     this.peerStore = peerStore
+    this.addressSorter = addressSorter
     this.concurrency = concurrency
     this.timeout = timeout
     this.perPeerLimit = perPeerLimit
@@ -120,7 +124,7 @@ class Dialer {
       this.peerStore.addressBook.add(id, multiaddrs)
     }
 
-    let knownAddrs = this.peerStore.addressBook.getMultiaddrsForPeer(id) || []
+    let knownAddrs = this.peerStore.addressBook.getMultiaddrsForPeer(id, this.addressSorter) || []
 
     // If received a multiaddr to dial, it should be the first to use
     // But, if we know other multiaddrs for the peer, we should try them too.

src/index.js

@@ -136,7 +136,8 @@ class Libp2p extends EventEmitter {
       concurrency: this._options.dialer.maxParallelDials,
       perPeerLimit: this._options.dialer.maxDialsPerPeer,
       timeout: this._options.dialer.dialTimeout,
-      resolvers: this._options.dialer.resolvers
+      resolvers: this._options.dialer.resolvers,
+      addressSorter: this._options.dialer.addressSorter
     })
 
     this._modules.transport.forEach((Transport) => {

src/peer-store/address-book.js

@@ -319,20 +319,22 @@ class AddressBook extends Book {
    * Returns `undefined` if there are no known multiaddrs for the given peer.
    *
    * @param {PeerId} peerId
+   * @param {(addresses: Array<Address) => Array<Address>} [addressSorter]
    * @returns {Array<Multiaddr>|undefined}
    */
-  getMultiaddrsForPeer (peerId) {
+  getMultiaddrsForPeer (peerId, addressSorter = (ms) => ms) {
     if (!PeerId.isPeerId(peerId)) {
       throw errcode(new Error('peerId must be an instance of peer-id'), ERR_INVALID_PARAMETERS)
     }
 
     const entry = this.data.get(peerId.toB58String())
-
     if (!entry || !entry.addresses) {
       return undefined
     }
 
-    return entry.addresses.map((address) => {
+    return addressSorter(
+      entry.addresses || []
+    ).map((address) => {
       const multiaddr = address.multiaddr
 
       const idString = multiaddr.getPeerId()