Modernize lib/tcp-pool.js

lib/tcp-pool.js

@@ -1,10 +1,8 @@
-module.exports = TCPPool
-
-var arrayRemove = require('unordered-array-remove')
-var debug = require('debug')('webtorrent:tcp-pool')
-var net = require('net') // browser exclude
+const arrayRemove = require('unordered-array-remove')
+const debug = require('debug')('webtorrent:tcp-pool')
+const net = require('net') // browser exclude
 
-var Peer = require('./peer')
+const Peer = require('./peer')
 
 /**
  * TCPPool
@@ -15,114 +13,116 @@ var Peer = require('./peer')
  *
  * @param {number} port
  */
-function TCPPool (client) {
-  var self = this
-  debug('create tcp pool (port %s)', client.torrentPort)
-
-  self.server = net.createServer()
-  self._client = client
+class TCPPool {
+  constructor (client) {
+    debug('create tcp pool (port %s)', client.torrentPort)
 
-  // Temporarily store incoming connections so they can be destroyed if the server is
-  // closed before the connection is passed off to a Torrent.
-  self._pendingConns = []
+    this.server = net.createServer()
+    this._client = client
 
-  self._onConnectionBound = function (conn) {
-    self._onConnection(conn)
-  }
+    // Temporarily store incoming connections so they can be destroyed if the server is
+    // closed before the connection is passed off to a Torrent.
+    this._pendingConns = []
 
-  self._onListening = function () {
-    self._client._onListening()
-  }
+    this._onConnectionBound = conn => {
+      this._onConnection(conn)
+    }
 
-  self._onError = function (err) {
-    self._client._destroy(err)
-  }
+    this._onListening = () => {
+      this._client._onListening()
+    }
 
-  self.server.on('connection', self._onConnectionBound)
-  self.server.on('listening', self._onListening)
-  self.server.on('error', self._onError)
+    this._onError = err => {
+      this._client._destroy(err)
+    }
 
-  self.server.listen(client.torrentPort)
-}
+    this.server.on('connection', this._onConnectionBound)
+    this.server.on('listening', this._onListening)
+    this.server.on('error', this._onError)
 
-/**
- * Destroy this TCP pool.
- * @param  {function} cb
- */
-TCPPool.prototype.destroy = function (cb) {
-  var self = this
-  debug('destroy tcp pool')
-
-  self.server.removeListener('connection', self._onConnectionBound)
-  self.server.removeListener('listening', self._onListening)
-  self.server.removeListener('error', self._onError)
-
-  // Destroy all open connection objects so server can close gracefully without waiting
-  // for connection timeout or remote peer to disconnect.
-  self._pendingConns.forEach(function (conn) {
-    conn.on('error', noop)
-    conn.destroy()
-  })
-
-  try {
-    self.server.close(cb)
-  } catch (err) {
-    if (cb) process.nextTick(cb)
+    this.server.listen(client.torrentPort)
   }
 
-  self.server = null
-  self._client = null
-  self._pendingConns = null
-}
+  /**
+   * Destroy this TCP pool.
+   * @param  {function} cb
+   */
+  destroy (cb) {
+    debug('destroy tcp pool')
+
+    this.server.removeListener('connection', this._onConnectionBound)
+    this.server.removeListener('listening', this._onListening)
+    this.server.removeListener('error', this._onError)
+
+    // Destroy all open connection objects so server can close gracefully without waiting
+    // for connection timeout or remote peer to disconnect.
+    this._pendingConns.forEach(conn => {
+      conn.on('error', noop)
+      conn.destroy()
+    })
+
+    try {
+      this.server.close(cb)
+    } catch (err) {
+      if (cb) process.nextTick(cb)
+    }
 
-/**
- * On incoming connections, we expect the remote peer to send a handshake first. Based
- * on the infoHash in that handshake, route the peer to the right swarm.
- */
-TCPPool.prototype._onConnection = function (conn) {
-  var self = this
-
-  // If the connection has already been closed before the `connect` event is fired,
-  // then `remoteAddress` will not be available, and we can't use this connection.
-  // - Node.js issue: https://github.com/nodejs/node-v0.x-archive/issues/7566
-  // - WebTorrent issue: https://github.com/webtorrent/webtorrent/issues/398
-  if (!conn.remoteAddress) {
-    conn.on('error', noop)
-    conn.destroy()
-    return
+    this.server = null
+    this._client = null
+    this._pendingConns = null
   }
 
-  self._pendingConns.push(conn)
-  conn.once('close', cleanupPending)
+  /**
+   * On incoming connections, we expect the remote peer to send a handshake first. Based
+   * on the infoHash in that handshake, route the peer to the right swarm.
+   */
+  _onConnection (conn) {
+    const self = this
+
+    // If the connection has already been closed before the `connect` event is fired,
+    // then `remoteAddress` will not be available, and we can't use this connection.
+    // - Node.js issue: https://github.com/nodejs/node-v0.x-archive/issues/7566
+    // - WebTorrent issue: https://github.com/webtorrent/webtorrent/issues/398
+    if (!conn.remoteAddress) {
+      conn.on('error', noop)
+      conn.destroy()
+      return
+    }
+
+    self._pendingConns.push(conn)
+    conn.once('close', cleanupPending)
 
-  var peer = Peer.createTCPIncomingPeer(conn)
+    const peer = Peer.createTCPIncomingPeer(conn)
 
-  var wire = peer.wire
-  wire.once('handshake', onHandshake)
+    const wire = peer.wire
+    wire.once('handshake', onHandshake)
 
-  function onHandshake (infoHash, peerId) {
-    cleanupPending()
+    function onHandshake (infoHash, peerId) {
+      cleanupPending()
 
-    var torrent = self._client.get(infoHash)
-    if (torrent) {
-      peer.swarm = torrent
-      torrent._addIncomingPeer(peer)
-      peer.onHandshake(infoHash, peerId)
-    } else {
-      var err = new Error(
-        'Unexpected info hash ' + infoHash + ' from incoming peer ' + peer.id
-      )
-      peer.destroy(err)
+      const torrent = self._client.get(infoHash)
+      if (torrent) {
+        peer.swarm = torrent
+        torrent._addIncomingPeer(peer)
+        peer.onHandshake(infoHash, peerId)
+      } else {
+        const err = new Error(
+          `Unexpected info hash ${infoHash} from incoming peer ${peer.id}`
+        )
+        peer.destroy(err)
+      }
     }
-  }
 
-  function cleanupPending () {
-    conn.removeListener('close', cleanupPending)
-    wire.removeListener('handshake', onHandshake)
-    if (self._pendingConns) {
-      arrayRemove(self._pendingConns, self._pendingConns.indexOf(conn))
+    function cleanupPending () {
+      conn.removeListener('close', cleanupPending)
+      wire.removeListener('handshake', onHandshake)
+      if (self._pendingConns) {
+        arrayRemove(self._pendingConns, self._pendingConns.indexOf(conn))
+      }
     }
   }
 }
 
 function noop () {}
+
+module.exports = TCPPool