Various code simplifications and fixes.

src/connection.js

@@ -2,43 +2,28 @@ import {EventEmitter} from 'events'
 
 // ===================================================================
 
-const has = (function () {
+// const noop = () => {}
-  return (val, prop) => hasOwnProperty.call(val, prop)
-})(Object.hasOwnProperty)
-
-const noop = () => {}
 
 // ===================================================================
 
 export default class Connection extends EventEmitter {
-  constructor ({close, notify}) {
+  constructor () {
     super()
 
-    this._close = close
+    this._data = Object.create(null)
-    this.data = Object.create(null)
-    this.notify = notify
   }
 
   // Close the connection.
   close () {
     // Prevent errors when the connection is closed more than once.
-    this.close = noop
+    // this.close = noop
-
-    this._close()
 
     this.emit('close')
-
-    // Releases values AMAP to ease the garbage collecting.
-    for (let key in this) {
-      if (key !== 'close' && has(this, key)) {
-        delete this[key]
-      }
-    }
   }
 
   // Gets the value for this key.
   get (key, defaultValue) {
-    const {data} = this
+    const {_data: data} = this
 
     if (key in data) {
       return data[key]
@@ -53,15 +38,15 @@ export default class Connection extends EventEmitter {
 
   // Checks whether there is a value for this key.
   has (key) {
-    return key in this.data
+    return key in this._data
   }
 
   // Sets the value for this key.
   set (key, value) {
-    this.data[key] = value
+    this._data[key] = value
   }
 
   unset (key) {
-    delete this.data[key]
+    delete this._data[key]
   }
 }

src/index.js

@@ -206,33 +206,32 @@ const setUpApi = (webServer, xo) => {
     path: '/api/'
   })
 
-  webSocketServer.on('connection', connection => {
+  webSocketServer.on('connection', socket => {
     debug('+ WebSocket connection')
 
-    let xoConnection
+    // Create the abstract XO object for this connection.
+    const connection = xo.createUserConnection()
+    connection.once('close', () => {
+      socket.close()
+    })
 
     // Create the JSON-RPC server for this connection.
     const jsonRpc = createJsonRpcServer(message => {
       if (message.type === 'request') {
-        return api.call(xoConnection, message.method, message.params)
+        return api.call(connection, message.method, message.params)
       }
     })
-
+    connection.notify = bind(jsonRpc.notify, jsonRpc)
-    // Create the abstract XO object for this connection.
-    xoConnection = xo.createUserConnection({
-      close: bind(connection.close, connection),
-      notify: bind(jsonRpc.notify, jsonRpc)
-    })
 
     // Close the XO connection with this WebSocket.
-    connection.once('close', () => {
+    socket.once('close', () => {
       debug('- WebSocket connection')
 
-      xoConnection.close()
+      connection.close()
     })
 
     // Connect the WebSocket to the JSON-RPC server.
-    connection.on('message', message => {
+    socket.on('message', message => {
       jsonRpc.write(message)
     })
 
@@ -242,7 +241,11 @@ const setUpApi = (webServer, xo) => {
       }
     }
     jsonRpc.on('data', data => {
-      connection.send(JSON.stringify(data), onSend)
+      // The socket may have been closed during the API method
+      // execution.
+      if (socket.readyState === WebSocket.OPEN) {
+        socket.send(JSON.stringify(data), onSend)
+      }
     })
   })
 }

src/xo.js

@@ -123,7 +123,9 @@ export default class Xo extends EventEmitter {
       let exited = {}
 
       let dispatcherRegistered = false
-      const dispatcher = () => {
+      const dispatcher = Bluebird.method(() => {
+        dispatcherRegistered = false
+
         const {connections} = this
 
         if (!isEmpty(entered)) {
@@ -131,6 +133,7 @@ export default class Xo extends EventEmitter {
             type: 'enter',
             items: pluck(entered, 'val')
           }
+          entered = {}
 
           for (let id in connections) {
             const connection = connections[id]
@@ -139,15 +142,14 @@ export default class Xo extends EventEmitter {
               connection.notify('all', enterParams)
             }
           }
-
-          entered = {}
         }
 
-        if (!isEmpty(entered)) {
+        if (!isEmpty(exited)) {
           const exitParams = {
             type: 'exit',
             items: pluck(exited, 'val')
           }
+          exited = {}
 
           for (let id in connections) {
             const connection = connections[id]
@@ -156,10 +158,8 @@ export default class Xo extends EventEmitter {
               connection.notify('all', exitParams)
             }
           }
-
-          exited = {}
         }
-      }
+      })
 
       this._xobjs.on('any', (event, items) => {
         if (!dispatcherRegistered) {
@@ -326,16 +326,16 @@ export default class Xo extends EventEmitter {
 
   // -----------------------------------------------------------------
 
-  createUserConnection (opts) {
+  createUserConnection () {
     const {connections} = this
 
-    const connection = new Connection(opts)
+    const connection = new Connection()
     const id = connection.id = this._nextConId++
-    connection.on('close', () => {
-      connections[id]
-    })
 
     connections[id] = connection
+    connection.on('close', () => {
+      delete connections[id]
+    })
 
     return connection
   }