fix: dialer leaking resources after stopping (#947)

* fix: dialer leaking resources after stopping

* chore: add error code to test

src/connection-manager/index.js

@@ -97,6 +97,11 @@ class ConnectionManager extends EventEmitter {
     this._autoDialTimeout = null
     this._checkMetrics = this._checkMetrics.bind(this)
     this._autoDial = this._autoDial.bind(this)
+
+    this._latencyMonitor = new LatencyMonitor({
+      latencyCheckIntervalMs: this._options.pollInterval,
+      dataEmitIntervalMs: this._options.pollInterval
+    })
   }
 
   /**
@@ -117,10 +122,7 @@ class ConnectionManager extends EventEmitter {
     }
 
     // latency monitor
-    this._latencyMonitor = new LatencyMonitor({
-      latencyCheckIntervalMs: this._options.pollInterval,
-      dataEmitIntervalMs: this._options.pollInterval
-    })
+    this._latencyMonitor.start()
     this._onLatencyMeasure = this._onLatencyMeasure.bind(this)
     this._latencyMonitor.on('data', this._onLatencyMeasure)
 
@@ -138,7 +140,9 @@ class ConnectionManager extends EventEmitter {
   async stop () {
     this._autoDialTimeout && this._autoDialTimeout.clear()
     this._timer && this._timer.clear()
-    this._latencyMonitor && this._latencyMonitor.removeListener('data', this._onLatencyMeasure)
+
+    this._latencyMonitor.removeListener('data', this._onLatencyMeasure)
+    this._latencyMonitor.stop()
 
     this._started = false
     await this._close()

src/connection-manager/latency-monitor.js

@@ -69,49 +69,55 @@ class LatencyMonitor extends EventEmitter {
     }
 
     that.asyncTestFn = asyncTestFn // If there is no asyncFn, we measure latency
+  }
 
+  start () {
     // If process: use high resolution timer
     if (globalThis.process && globalThis.process.hrtime) { // eslint-disable-line no-undef
       debug('Using process.hrtime for timing')
-      that.now = globalThis.process.hrtime // eslint-disable-line no-undef
-      that.getDeltaMS = (startTime) => {
-        const hrtime = that.now(startTime)
+      this.now = globalThis.process.hrtime // eslint-disable-line no-undef
+      this.getDeltaMS = (startTime) => {
+        const hrtime = this.now(startTime)
         return (hrtime[0] * 1000) + (hrtime[1] / 1000000)
       }
       // Let's try for a timer that only monotonically increases
     } else if (typeof window !== 'undefined' && window.performance && window.performance.now) {
       debug('Using performance.now for timing')
-      that.now = window.performance.now.bind(window.performance)
-      that.getDeltaMS = (startTime) => Math.round(that.now() - startTime)
+      this.now = window.performance.now.bind(window.performance)
+      this.getDeltaMS = (startTime) => Math.round(this.now() - startTime)
     } else {
       debug('Using Date.now for timing')
-      that.now = Date.now
-      that.getDeltaMS = (startTime) => that.now() - startTime
+      this.now = Date.now
+      this.getDeltaMS = (startTime) => this.now() - startTime
     }
 
-    that._latencyData = that._initLatencyData()
+    this._latencyData = this._initLatencyData()
 
     // We check for isBrowser because of browsers set max rates of timeouts when a page is hidden,
     // so we fall back to another library
     // See: http://stackoverflow.com/questions/6032429/chrome-timeouts-interval-suspended-in-background-tabs
     if (isBrowser()) {
-      that._visibilityChangeEmitter = new VisibilityChangeEmitter()
+      this._visibilityChangeEmitter = new VisibilityChangeEmitter()
 
-      that._visibilityChangeEmitter.on('visibilityChange', (pageInFocus) => {
+      this._visibilityChangeEmitter.on('visibilityChange', (pageInFocus) => {
         if (pageInFocus) {
-          that._startTimers()
+          this._startTimers()
         } else {
-          that._emitSummary()
-          that._stopTimers()
+          this._emitSummary()
+          this._stopTimers()
         }
       })
     }
 
-    if (!that._visibilityChangeEmitter || that._visibilityChangeEmitter.isVisible()) {
-      that._startTimers()
+    if (!this._visibilityChangeEmitter || this._visibilityChangeEmitter.isVisible()) {
+      this._startTimers()
     }
   }
 
+  stop () {
+    this._stopTimers()
+  }
+
   /**
    * Start internal timers
    *

src/dialer/index.js

@@ -8,6 +8,7 @@ const errCode = require('err-code')
 const { Multiaddr } = require('multiaddr')
 // @ts-ignore timeout-abourt-controles does not export types
 const TimeoutController = require('timeout-abort-controller')
+const { AbortError } = require('abortable-iterator')
 const { anySignal } = require('any-signal')
 
 const DialRequest = require('./dial-request')
@@ -76,6 +77,7 @@ class Dialer {
     this.maxDialsPerPeer = maxDialsPerPeer
     this.tokens = [...new Array(maxParallelDials)].map((_, index) => index)
     this._pendingDials = new Map()
+    this._pendingDialTargets = new Map()
 
     for (const [key, value] of Object.entries(resolvers)) {
       Multiaddr.resolvers.set(key, value)
@@ -94,6 +96,11 @@ class Dialer {
       }
     }
     this._pendingDials.clear()
+
+    for (const pendingTarget of this._pendingDialTargets.values()) {
+      pendingTarget.reject(new AbortError('Dialer was destroyed'))
+    }
+    this._pendingDialTargets.clear()
   }
 
   /**
@@ -107,7 +114,7 @@ class Dialer {
    * @returns {Promise<Connection>}
    */
   async connectToPeer (peer, options = {}) {
-    const dialTarget = await this._createDialTarget(peer)
+    const dialTarget = await this._createCancellableDialTarget(peer)
 
     if (!dialTarget.addrs.length) {
       throw errCode(new Error('The dial request has no valid addresses'), codes.ERR_NO_VALID_ADDRESSES)
@@ -130,6 +137,31 @@ class Dialer {
     }
   }
 
+  /**
+   * Connects to a given `peer` by dialing all of its known addresses.
+   * The dial to the first address that is successfully able to upgrade a connection
+   * will be used.
+   *
+   * @param {PeerId|Multiaddr|string} peer - The peer to dial
+   * @returns {Promise<DialTarget>}
+   */
+  async _createCancellableDialTarget (peer) {
+    // Make dial target promise cancellable
+    const id = `${(parseInt(String(Math.random() * 1e9), 10)).toString() + Date.now()}`
+    const cancellablePromise = new Promise((resolve, reject) => {
+      this._pendingDialTargets.set(id, { resolve, reject })
+    })
+
+    const dialTarget = await Promise.race([
+      this._createDialTarget(peer),
+      cancellablePromise
+    ])
+
+    this._pendingDialTargets.delete(id)
+
+    return dialTarget
+  }
+
   /**
    * Creates a DialTarget. The DialTarget is used to create and track
    * the DialRequest to a given peer.

test/dialing/direct.spec.js

@@ -290,6 +290,34 @@ describe('Dialing (direct, WebSockets)', () => {
     }
   })
 
+  it('should cancel pending dial targets before proceeding', async () => {
+    const dialer = new Dialer({
+      transportManager: localTM,
+      peerStore: {
+        addressBook: {
+          set: () => { }
+        }
+      }
+    })
+
+    sinon.stub(dialer, '_createDialTarget').callsFake(() => {
+      const deferredDial = pDefer()
+      return deferredDial.promise
+    })
+
+    // Perform dial
+    const dialPromise = dialer.connectToPeer(peerId)
+
+    // Let the call stack run
+    await delay(0)
+
+    dialer.destroy()
+
+    await expect(dialPromise)
+      .to.eventually.be.rejected()
+      .and.to.have.property('code', 'ABORT_ERR')
+  })
+
   describe('libp2p.dialer', () => {
     const transportKey = Transport.prototype[Symbol.toStringTag]
     let libp2p
@@ -462,6 +490,42 @@ describe('Dialing (direct, WebSockets)', () => {
       await libp2p.hangUp(remoteAddr)
     })
 
+    it('should cancel pending dial targets and stop', async () => {
+      const [, remotePeerId] = await createPeerId({ number: 2 })
+
+      libp2p = new Libp2p({
+        peerId,
+        modules: {
+          transport: [Transport],
+          streamMuxer: [Muxer],
+          connEncryption: [Crypto]
+        },
+        config: {
+          transport: {
+            [transportKey]: {
+              filter: filters.all
+            }
+          }
+        }
+      })
+
+      sinon.stub(libp2p.dialer, '_createDialTarget').callsFake(() => {
+        const deferredDial = pDefer()
+        return deferredDial.promise
+      })
+
+      // Perform dial
+      const dialPromise = libp2p.dial(remotePeerId)
+
+      // Let the call stack run
+      await delay(0)
+
+      await libp2p.stop()
+      await expect(dialPromise)
+        .to.eventually.be.rejected()
+        .and.to.have.property('code', 'ABORT_ERR')
+    })
+
     it('should abort pending dials on stop', async () => {
       libp2p = new Libp2p({
         peerId,