IPC removed, replaced by WS

2020-04-06 08:33:07 +02:00
1 parent ba4217fb24
commit 656c193511
@@ -0,0 +1,12 @@
+
+INTER_PROCESS_FILES_PATH=../Inter-Process-Files
+STORAGE_PATH=../Data-Storage
+PLOTTERS_PATH=../Legacy-Code
+
+USE_KEYVAULT=false 
+WRITE_LOGS_TO_FILES=true
+BOTS_PATH=../Legacy-Code
+LOG_PATH=../Log-Files
+
+WEB_SOCKETS_SERVER_PORT=8080
+
@@ -0,0 +1,222 @@
+exports.newEventsServer = function newEventsServer() {
+
+    const MODULE = "Events Server"
+    const LOG_INFO = false
+
+    let thisObject = {
+        initialize: initialize,
+        finalize: finalize,
+        run: run,
+        onMessage: onMessage
+    }
+
+    let eventHandlers = new Map()
+    let counter = 0
+
+    return thisObject
+
+    function finalize() {
+
+    }
+
+    function initialize() {
+
+    }
+
+    function onMessage(data, callbackFunction) {
+        try {
+            let command = JSON.parse(data)
+
+            switch (command.action) {
+                case "greetings": {
+                    sendResponse(global.DEFAULT_OK_RESPONSE)
+                    return
+                }
+                case "createEventHandler": {
+                    let eventHandler = eventHandlers.get(command.eventHandlerName)
+                    if (eventHandler === undefined) {
+                        /*
+                        We will only create event handlers which were not created before. Remember that someone trying to listen events
+                        at an event handler that does not exist, will create that eventhandler, so it is possible that the emitter
+                        when trying to create the event handler in fact was late and the event handler is already there if the listener
+                        arrived here first. An event handler created with this method is not destroyed if there are no listeners or they
+                        all leave.
+                        */
+                        eventHandler = newEventHandler()
+                        eventHandler.deleteWhenAllListenersAreGone = false
+                        eventHandlers.set(command.eventHandlerName, eventHandler)
+                    }
+                    sendResponse(global.DEFAULT_OK_RESPONSE)
+                    return
+                }
+                case "deleteEventHandler": {
+                    let eventHandler = eventHandlers.get(command.eventHandlerName)
+                    if (eventHandler !== undefined) {
+                        /*
+                        We will only delete event handlers which have noone listening, allowing a listener to continue listening even
+                        when the event emitter is gone, asuming that it could come back at some point in time and resume emitting.
+                        */
+                        if (eventHandler.listeners.length === 0) {
+                            eventHandlers.delete(command.eventHandlerName)
+                        } else {
+                            eventHandler.deleteWhenAllListenersAreGone = true
+                        }
+                    }
+
+                    sendResponse(global.DEFAULT_OK_RESPONSE)
+                    return
+                }
+                case "listenToEvent": {
+                    let eventHandler = eventHandlers.get(command.eventHandlerName)
+                    if (eventHandler === undefined) {
+                        /*
+                        We will create event handlers which were not created before if a listener tries to listen to a handler that does noet
+                        exist before the emitter comes and create it. This is to aviod syncronization problems and also problems with emitters life
+                        cycles with higher frecuency that the ones of listeners. Created in this way, event handlers are marked for deletion if
+                        all listeners stop listening at one point in time.
+                        */
+                        eventHandler = newEventHandler()
+                        eventHandler.deleteWhenAllListenersAreGone = true
+                        eventHandlers.set(command.eventHandlerName, eventHandler)
+                    }
+                    eventSubscriptionId = eventHandler.listenToEvent(command.eventHandlerName, command.eventType, command.callerId, handlerFunction, command.extraData)
+
+                    function handlerFunction(event, extraData) {
+                        let outputData = {
+                            action: 'Event Raised',
+                            eventHandlerName: command.eventHandlerName,
+                            eventType: command.eventType,
+                            event: event,
+                            callerId: command.callerId,
+                            extraData: extraData
+                        }
+                        callbackFunction(JSON.stringify(outputData))
+                    }
+
+                    let response = {
+                        result: global.DEFAULT_OK_RESPONSE.result,
+                        message: global.DEFAULT_OK_RESPONSE.message,
+                        eventSubscriptionId: eventSubscriptionId
+                    }
+
+                    sendResponse(response)
+                    return
+                }
+                case "stopListening": {
+                    let eventHandler = eventHandlers.get(command.eventHandlerName)
+
+                    if (eventHandler === undefined) {
+
+                        /* If the event handler does not exist anymore, then there is no need to perform further actiions.  */
+                        sendResponse(global.DEFAULT_OK_RESPONSE)
+                        return
+                    }
+
+                    eventHandler.stopListening(command.eventHandlerName, command.eventType, command.callerId, command.eventSubscriptionId)
+
+                    /*
+                    We check here if there are no more listeners and the event handler original emmiter is also gone, then we need to delete
+                    this event handlers since chances are that is not needed anymore.
+                    */
+                    if (eventHandler.listeners.length === 0 && eventHandler.deleteWhenAllListenersAreGone === true) {
+                        eventHandlers.delete(command.eventHandlerName)
+                    }
+
+                    sendResponse(global.DEFAULT_OK_RESPONSE)
+                    return
+                }
+                case "raiseEvent": {
+                    let eventHandler = eventHandlers.get(command.eventHandlerName)
+
+                    if (eventHandler === undefined) {
+
+                        eventHandler = newEventHandler()
+                        eventHandlers.set(command.eventHandlerName, eventHandler)
+
+                        /* No matter if it is the listener or the emiter the one that acts first, if an event handler does not exist we just create it acan keep it there. */
+
+                    }
+                    //console.log("[INFO] BackendServers -> Events Server -> Raising Event " + command.eventHandlerName + " " + command.eventType)
+                    eventHandler.raiseEvent(command.eventType, command.event)
+                    sendResponse(global.DEFAULT_OK_RESPONSE)
+                    return
+                }
+            }
+
+            console.log("[WARN] BackendServers -> Events Server -> onMessage -> Unknown Command Received:" + data)
+
+            function sendResponse(message) {
+                if (command.callerId !== undefined) {
+                    message.callerId = command.callerId
+                }
+                message.action = 'Event Server Response'
+                callbackFunction(JSON.stringify(message))
+            }
+
+        } catch (err) {
+            console.log("[ERROR] BackendServers -> Events Server -> onMessage -> Bad Command Received:" + data)
+            console.log("[ERROR] BackendServers -> Events Server -> onMessage -> An Error Happened:" + err.stack)
+        }
+    }
+
+    function run() {
+        console.log('Events Server Started.')
+    }
+
+    function newEventHandler() {
+        let thisObject = {
+            name: undefined,                            // This is for debugging purposes only.
+            deleteWhenAllListenersAreGone: false,
+            listeners: [],                              // Here we store all the functions we will call when an event is raiseed.
+            listenToEvent: listenToEvent,
+            stopListening: stopListening,
+            raiseEvent: raiseEvent,
+            finalize: finalize
+        }
+
+        return thisObject
+
+        function finalize() {
+            thisObject.listeners = []
+        }
+
+        function listenToEvent(eventHandlerName, eventType, callerId, handler, extraData) {
+            let eventSubscriptionId = Math.trunc(Math.random() * 1000000)
+            thisObject.listeners.push([eventHandlerName, eventType, callerId, handler, extraData, eventSubscriptionId])
+            return eventSubscriptionId
+        }
+
+        function stopListening(eventHandlerName, eventType, callerId, eventSubscriptionId) {
+
+            if (eventSubscriptionId !== undefined) {
+                for (let i = 0; i < thisObject.listeners.length; i++) {
+                    if (eventSubscriptionId === thisObject.listeners[i][5]) {
+                        thisObject.listeners.splice(i, 1)
+                        return
+                    }
+                }
+            }
+            if (eventHandlerName !== undefined && eventType !== undefined && callerId !== undefined) {
+                for (let i = 0; i < thisObject.listeners.length; i++) {
+                    if (eventHandlerName === thisObject.listeners[i][0] && eventType === thisObject.listeners[i][1] && callerId === thisObject.listeners[i][2]) {
+                        thisObject.listeners.splice(i, 1)
+                        return
+                    }
+                }
+            }
+        }
+
+        function raiseEvent(eventType, event) {
+            for (let i = 0; i < thisObject.listeners.length; i++) {
+                /* We will execute all the functions listening to this event type. */
+
+                if (thisObject.listeners[i][1] === eventType) {
+                    let handler = thisObject.listeners[i][3]
+                    let extraData = thisObject.listeners[i][4]
+
+                    handler(event, extraData)
+                }
+            }
+        }
+    }
+}
@@ -0,0 +1,45 @@
+{
+  "_from": "child_process@^1.0.2",
+  "_id": "child_process@1.0.2",
+  "_inBundle": false,
+  "_integrity": "sha1-sffn/HPSXn/R1FWtyU4UODAYK1o=",
+  "_location": "/child_process",
+  "_phantomChildren": {},
+  "_requested": {
+    "type": "range",
+    "registry": true,
+    "raw": "child_process@^1.0.2",
+    "name": "child_process",
+    "escapedName": "child_process",
+    "rawSpec": "^1.0.2",
+    "saveSpec": null,
+    "fetchSpec": "^1.0.2"
+  },
+  "_requiredBy": [
+    "/"
+  ],
+  "_resolved": "https://registry.npmjs.org/child_process/-/child_process-1.0.2.tgz",
+  "_shasum": "b1f7e7fc73d25e7fd1d455adc94e143830182b5a",
+  "_spec": "child_process@^1.0.2",
+  "_where": "C:\\Users\\Luis\\source\\repos\\AAMasters\\BackendServers",
+  "author": "",
+  "bugs": {
+    "url": "https://github.com/npm/security-holder/issues"
+  },
+  "bundleDependencies": false,
+  "deprecated": false,
+  "description": "This package name is not currently in use, but was formerly occupied by another package. To avoid malicious use, npm is hanging on to the package name, but loosely, and we'll probably give it to you if you want it.",
+  "homepage": "https://github.com/npm/security-holder#readme",
+  "keywords": [],
+  "license": "ISC",
+  "main": "index.js",
+  "name": "child_process",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/npm/security-holder.git"
+  },
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "version": "1.0.2"
+}
@@ -0,0 +1,11 @@
+/* @flow */
+
+(function () {
+  require('./lib/main').config(
+    Object.assign(
+      {},
+      require('./lib/env-options'),
+      require('./lib/cli-options')(process.argv)
+    )
+  )
+})()
@@ -0,0 +1,13 @@
+/* @flow */
+
+const re = /^dotenv_config_(encoding|path|debug)=(.+)$/
+
+module.exports = function optionMatcher (args /*: Array<string> */) {
+  return args.reduce(function (acc, cur) {
+    const matches = cur.match(re)
+    if (matches) {
+      acc[matches[1]] = matches[2]
+    }
+    return acc
+  }, {})
+}
@@ -0,0 +1,18 @@
+/* @flow */
+
+// ../config.js accepts options via environment variables
+const options = {}
+
+if (process.env.DOTENV_CONFIG_ENCODING != null) {
+  options.encoding = process.env.DOTENV_CONFIG_ENCODING
+}
+
+if (process.env.DOTENV_CONFIG_PATH != null) {
+  options.path = process.env.DOTENV_CONFIG_PATH
+}
+
+if (process.env.DOTENV_CONFIG_DEBUG != null) {
+  options.debug = process.env.DOTENV_CONFIG_DEBUG
+}
+
+module.exports = options
@@ -0,0 +1,113 @@
+/* @flow */
+/*::
+
+type DotenvParseOptions = {
+  debug?: boolean
+}
+
+// keys and values from src
+type DotenvParseOutput = { [string]: string }
+
+type DotenvConfigOptions = {
+  path?: string, // path to .env file
+  encoding?: string, // encoding of .env file
+  debug?: string // turn on logging for debugging purposes
+}
+
+type DotenvConfigOutput = {
+  parsed?: DotenvParseOutput,
+  error?: Error
+}
+
+*/
+
+const fs = require('fs')
+const path = require('path')
+
+function log (message /*: string */) {
+  console.log(`[dotenv][DEBUG] ${message}`)
+}
+
+const NEWLINE = '\n'
+const RE_INI_KEY_VAL = /^\s*([\w.-]+)\s*=\s*(.*)?\s*$/
+const RE_NEWLINES = /\\n/g
+const NEWLINES_MATCH = /\n|\r|\r\n/
+
+// Parses src into an Object
+function parse (src /*: string | Buffer */, options /*: ?DotenvParseOptions */) /*: DotenvParseOutput */ {
+  const debug = Boolean(options && options.debug)
+  const obj = {}
+
+  // convert Buffers before splitting into lines and processing
+  src.toString().split(NEWLINES_MATCH).forEach(function (line, idx) {
+    // matching "KEY' and 'VAL' in 'KEY=VAL'
+    const keyValueArr = line.match(RE_INI_KEY_VAL)
+    // matched?
+    if (keyValueArr != null) {
+      const key = keyValueArr[1]
+      // default undefined or missing values to empty string
+      let val = (keyValueArr[2] || '')
+      const end = val.length - 1
+      const isDoubleQuoted = val[0] === '"' && val[end] === '"'
+      const isSingleQuoted = val[0] === "'" && val[end] === "'"
+
+      // if single or double quoted, remove quotes
+      if (isSingleQuoted || isDoubleQuoted) {
+        val = val.substring(1, end)
+
+        // if double quoted, expand newlines
+        if (isDoubleQuoted) {
+          val = val.replace(RE_NEWLINES, NEWLINE)
+        }
+      } else {
+        // remove surrounding whitespace
+        val = val.trim()
+      }
+
+      obj[key] = val
+    } else if (debug) {
+      log(`did not match key and value when parsing line ${idx + 1}: ${line}`)
+    }
+  })
+
+  return obj
+}
+
+// Populates process.env from .env file
+function config (options /*: ?DotenvConfigOptions */) /*: DotenvConfigOutput */ {
+  let dotenvPath = path.resolve(process.cwd(), '.env')
+  let encoding /*: string */ = 'utf8'
+  let debug = false
+
+  if (options) {
+    if (options.path != null) {
+      dotenvPath = options.path
+    }
+    if (options.encoding != null) {
+      encoding = options.encoding
+    }
+    if (options.debug != null) {
+      debug = true
+    }
+  }
+
+  try {
+    // specifying an encoding returns a string instead of a buffer
+    const parsed = parse(fs.readFileSync(dotenvPath, { encoding }), { debug })
+
+    Object.keys(parsed).forEach(function (key) {
+      if (!Object.prototype.hasOwnProperty.call(process.env, key)) {
+        process.env[key] = parsed[key]
+      } else if (debug) {
+        log(`"${key}" is already defined in \`process.env\` and will not be overwritten`)
+      }
+    })
+
+    return { parsed }
+  } catch (e) {
+    return { error: e }
+  }
+}
+
+module.exports.config = config
+module.exports.parse = parse
@@ -0,0 +1,79 @@
+{
+  "_from": "dotenv@^8.2.0",
+  "_id": "dotenv@8.2.0",
+  "_inBundle": false,
+  "_integrity": "sha512-8sJ78ElpbDJBHNeBzUbUVLsqKdccaa/BXF1uPTw3GrvQTBgrQrtObr2mUrE38vzYd8cEv+m/JBfDLioYcfXoaw==",
+  "_location": "/dotenv",
+  "_phantomChildren": {},
+  "_requested": {
+    "type": "range",
+    "registry": true,
+    "raw": "dotenv@^8.2.0",
+    "name": "dotenv",
+    "escapedName": "dotenv",
+    "rawSpec": "^8.2.0",
+    "saveSpec": null,
+    "fetchSpec": "^8.2.0"
+  },
+  "_requiredBy": [
+    "/"
+  ],
+  "_resolved": "https://registry.npmjs.org/dotenv/-/dotenv-8.2.0.tgz",
+  "_shasum": "97e619259ada750eea3e4ea3e26bceea5424b16a",
+  "_spec": "dotenv@^8.2.0",
+  "_where": "C:\\Users\\Luis\\source\\repos\\AAMasters\\BackendServers",
+  "bugs": {
+    "url": "https://github.com/motdotla/dotenv/issues"
+  },
+  "bundleDependencies": false,
+  "dependencies": {},
+  "deprecated": false,
+  "description": "Loads environment variables from .env file",
+  "devDependencies": {
+    "decache": "^4.5.1",
+    "dtslint": "^0.9.8",
+    "flow-bin": "^0.109.0",
+    "sinon": "^7.5.0",
+    "standard": "^13.1.0",
+    "standard-markdown": "^5.1.0",
+    "standard-version": "^7.0.0",
+    "tap": "^14.7.0"
+  },
+  "engines": {
+    "node": ">=8"
+  },
+  "homepage": "https://github.com/motdotla/dotenv#readme",
+  "keywords": [
+    "dotenv",
+    "env",
+    ".env",
+    "environment",
+    "variables",
+    "config",
+    "settings"
+  ],
+  "license": "BSD-2-Clause",
+  "main": "lib/main.js",
+  "name": "dotenv",
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/motdotla/dotenv.git"
+  },
+  "scripts": {
+    "dtslint": "dtslint types",
+    "flow": "flow",
+    "lint": "standard",
+    "postlint": "standard-markdown",
+    "prerelease": "npm test",
+    "pretest": "npm run lint && npm run dtslint",
+    "release": "standard-version",
+    "test": "tap tests/*.js --100"
+  },
+  "standard": {
+    "ignore": [
+      "flow-typed/"
+    ]
+  },
+  "types": "types",
+  "version": "8.2.0"
+}
@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "lib": ["es6"],
+    "noImplicitAny": true,
+    "noImplicitThis": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "noEmit": true,
+    "baseUrl": ".",
+    "paths": {
+      "dotenv": ["."]
+    }
+  }
+}
@@ -0,0 +1,6 @@
+{
+  "extends": "dtslint/dtslint.json",
+  "rules": {
+    "strict-export-declare-modifiers": false
+  }
+}
@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = function() {
+  throw new Error(
+    'ws does not work in the browser. Browser clients must use the native ' +
+      'WebSocket object'
+  );
+};
@@ -0,0 +1,10 @@
+'use strict';
+
+const WebSocket = require('./lib/websocket');
+
+WebSocket.createWebSocketStream = require('./lib/stream');
+WebSocket.Server = require('./lib/websocket-server');
+WebSocket.Receiver = require('./lib/receiver');
+WebSocket.Sender = require('./lib/sender');
+
+module.exports = WebSocket;
@@ -0,0 +1,146 @@
+'use strict';
+
+const { EMPTY_BUFFER } = require('./constants');
+
+/**
+ * Merges an array of buffers into a new buffer.
+ *
+ * @param {Buffer[]} list The array of buffers to concat
+ * @param {Number} totalLength The total length of buffers in the list
+ * @return {Buffer} The resulting buffer
+ * @public
+ */
+function concat(list, totalLength) {
+  if (list.length === 0) return EMPTY_BUFFER;
+  if (list.length === 1) return list[0];
+
+  const target = Buffer.allocUnsafe(totalLength);
+  let offset = 0;
+
+  for (let i = 0; i < list.length; i++) {
+    const buf = list[i];
+    target.set(buf, offset);
+    offset += buf.length;
+  }
+
+  if (offset < totalLength) return target.slice(0, offset);
+
+  return target;
+}
+
+/**
+ * Masks a buffer using the given mask.
+ *
+ * @param {Buffer} source The buffer to mask
+ * @param {Buffer} mask The mask to use
+ * @param {Buffer} output The buffer where to store the result
+ * @param {Number} offset The offset at which to start writing
+ * @param {Number} length The number of bytes to mask.
+ * @public
+ */
+function _mask(source, mask, output, offset, length) {
+  for (let i = 0; i < length; i++) {
+    output[offset + i] = source[i] ^ mask[i & 3];
+  }
+}
+
+/**
+ * Unmasks a buffer using the given mask.
+ *
+ * @param {Buffer} buffer The buffer to unmask
+ * @param {Buffer} mask The mask to use
+ * @public
+ */
+function _unmask(buffer, mask) {
+  // Required until https://github.com/nodejs/node/issues/9006 is resolved.
+  const length = buffer.length;
+  for (let i = 0; i < length; i++) {
+    buffer[i] ^= mask[i & 3];
+  }
+}
+
+/**
+ * Converts a buffer to an `ArrayBuffer`.
+ *
+ * @param {Buffer} buf The buffer to convert
+ * @return {ArrayBuffer} Converted buffer
+ * @public
+ */
+function toArrayBuffer(buf) {
+  if (buf.byteLength === buf.buffer.byteLength) {
+    return buf.buffer;
+  }
+
+  return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
+}
+
+/**
+ * Converts `data` to a `Buffer`.
+ *
+ * @param {*} data The data to convert
+ * @return {Buffer} The buffer
+ * @throws {TypeError}
+ * @public
+ */
+function toBuffer(data) {
+  toBuffer.readOnly = true;
+
+  if (Buffer.isBuffer(data)) return data;
+
+  let buf;
+
+  if (data instanceof ArrayBuffer) {
+    buf = Buffer.from(data);
+  } else if (ArrayBuffer.isView(data)) {
+    buf = viewToBuffer(data);
+  } else {
+    buf = Buffer.from(data);
+    toBuffer.readOnly = false;
+  }
+
+  return buf;
+}
+
+/**
+ * Converts an `ArrayBuffer` view into a buffer.
+ *
+ * @param {(DataView|TypedArray)} view The view to convert
+ * @return {Buffer} Converted view
+ * @private
+ */
+function viewToBuffer(view) {
+  const buf = Buffer.from(view.buffer);
+
+  if (view.byteLength !== view.buffer.byteLength) {
+    return buf.slice(view.byteOffset, view.byteOffset + view.byteLength);
+  }
+
+  return buf;
+}
+
+try {
+  const bufferUtil = require('bufferutil');
+  const bu = bufferUtil.BufferUtil || bufferUtil;
+
+  module.exports = {
+    concat,
+    mask(source, mask, output, offset, length) {
+      if (length < 48) _mask(source, mask, output, offset, length);
+      else bu.mask(source, mask, output, offset, length);
+    },
+    toArrayBuffer,
+    toBuffer,
+    unmask(buffer, mask) {
+      if (buffer.length < 32) _unmask(buffer, mask);
+      else bu.unmask(buffer, mask);
+    }
+  };
+} catch (e) /* istanbul ignore next */ {
+  module.exports = {
+    concat,
+    mask: _mask,
+    toArrayBuffer,
+    toBuffer,
+    unmask: _unmask
+  };
+}
@@ -0,0 +1,10 @@
+'use strict';
+
+module.exports = {
+  BINARY_TYPES: ['nodebuffer', 'arraybuffer', 'fragments'],
+  GUID: '258EAFA5-E914-47DA-95CA-C5AB0DC85B11',
+  kStatusCode: Symbol('status-code'),
+  kWebSocket: Symbol('websocket'),
+  EMPTY_BUFFER: Buffer.alloc(0),
+  NOOP: () => {}
+};
@@ -0,0 +1,170 @@
+'use strict';
+
+/**
+ * Class representing an event.
+ *
+ * @private
+ */
+class Event {
+  /**
+   * Create a new `Event`.
+   *
+   * @param {String} type The name of the event
+   * @param {Object} target A reference to the target to which the event was dispatched
+   */
+  constructor(type, target) {
+    this.target = target;
+    this.type = type;
+  }
+}
+
+/**
+ * Class representing a message event.
+ *
+ * @extends Event
+ * @private
+ */
+class MessageEvent extends Event {
+  /**
+   * Create a new `MessageEvent`.
+   *
+   * @param {(String|Buffer|ArrayBuffer|Buffer[])} data The received data
+   * @param {WebSocket} target A reference to the target to which the event was dispatched
+   */
+  constructor(data, target) {
+    super('message', target);
+
+    this.data = data;
+  }
+}
+
+/**
+ * Class representing a close event.
+ *
+ * @extends Event
+ * @private
+ */
+class CloseEvent extends Event {
+  /**
+   * Create a new `CloseEvent`.
+   *
+   * @param {Number} code The status code explaining why the connection is being closed
+   * @param {String} reason A human-readable string explaining why the connection is closing
+   * @param {WebSocket} target A reference to the target to which the event was dispatched
+   */
+  constructor(code, reason, target) {
+    super('close', target);
+
+    this.wasClean = target._closeFrameReceived && target._closeFrameSent;
+    this.reason = reason;
+    this.code = code;
+  }
+}
+
+/**
+ * Class representing an open event.
+ *
+ * @extends Event
+ * @private
+ */
+class OpenEvent extends Event {
+  /**
+   * Create a new `OpenEvent`.
+   *
+   * @param {WebSocket} target A reference to the target to which the event was dispatched
+   */
+  constructor(target) {
+    super('open', target);
+  }
+}
+
+/**
+ * Class representing an error event.
+ *
+ * @extends Event
+ * @private
+ */
+class ErrorEvent extends Event {
+  /**
+   * Create a new `ErrorEvent`.
+   *
+   * @param {Object} error The error that generated this event
+   * @param {WebSocket} target A reference to the target to which the event was dispatched
+   */
+  constructor(error, target) {
+    super('error', target);
+
+    this.message = error.message;
+    this.error = error;
+  }
+}
+
+/**
+ * This provides methods for emulating the `EventTarget` interface. It's not
+ * meant to be used directly.
+ *
+ * @mixin
+ */
+const EventTarget = {
+  /**
+   * Register an event listener.
+   *
+   * @param {String} method A string representing the event type to listen for
+   * @param {Function} listener The listener to add
+   * @public
+   */
+  addEventListener(method, listener) {
+    if (typeof listener !== 'function') return;
+
+    function onMessage(data) {
+      listener.call(this, new MessageEvent(data, this));
+    }
+
+    function onClose(code, message) {
+      listener.call(this, new CloseEvent(code, message, this));
+    }
+
+    function onError(error) {
+      listener.call(this, new ErrorEvent(error, this));
+    }
+
+    function onOpen() {
+      listener.call(this, new OpenEvent(this));
+    }
+
+    if (method === 'message') {
+      onMessage._listener = listener;
+      this.on(method, onMessage);
+    } else if (method === 'close') {
+      onClose._listener = listener;
+      this.on(method, onClose);
+    } else if (method === 'error') {
+      onError._listener = listener;
+      this.on(method, onError);
+    } else if (method === 'open') {
+      onOpen._listener = listener;
+      this.on(method, onOpen);
+    } else {
+      this.on(method, listener);
+    }
+  },
+
+  /**
+   * Remove an event listener.
+   *
+   * @param {String} method A string representing the event type to remove
+   * @param {Function} listener The listener to remove
+   * @public
+   */
+  removeEventListener(method, listener) {
+    const listeners = this.listeners(method);
+
+    for (let i = 0; i < listeners.length; i++) {
+      if (listeners[i] === listener || listeners[i]._listener === listener) {
+        this.removeListener(method, listeners[i]);
+      }
+    }
+  }
+};
+
+module.exports = EventTarget;
@@ -0,0 +1,223 @@
+'use strict';
+
+//
+// Allowed token characters:
+//
+// '!', '#', '$', '%', '&', ''', '*', '+', '-',
+// '.', 0-9, A-Z, '^', '_', '`', a-z, '|', '~'
+//
+// tokenChars[32] === 0 // ' '
+// tokenChars[33] === 1 // '!'
+// tokenChars[34] === 0 // '"'
+// ...
+//
+// prettier-ignore
+const tokenChars = [
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 0 - 15
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 16 - 31
+  0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, // 32 - 47
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, // 48 - 63
+  0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 64 - 79
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, // 80 - 95
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 96 - 111
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0 // 112 - 127
+];
+
+/**
+ * Adds an offer to the map of extension offers or a parameter to the map of
+ * parameters.
+ *
+ * @param {Object} dest The map of extension offers or parameters
+ * @param {String} name The extension or parameter name
+ * @param {(Object|Boolean|String)} elem The extension parameters or the
+ *     parameter value
+ * @private
+ */
+function push(dest, name, elem) {
+  if (dest[name] === undefined) dest[name] = [elem];
+  else dest[name].push(elem);
+}
+
+/**
+ * Parses the `Sec-WebSocket-Extensions` header into an object.
+ *
+ * @param {String} header The field value of the header
+ * @return {Object} The parsed object
+ * @public
+ */
+function parse(header) {
+  const offers = Object.create(null);
+
+  if (header === undefined || header === '') return offers;
+
+  let params = Object.create(null);
+  let mustUnescape = false;
+  let isEscaping = false;
+  let inQuotes = false;
+  let extensionName;
+  let paramName;
+  let start = -1;
+  let end = -1;
+  let i = 0;
+
+  for (; i < header.length; i++) {
+    const code = header.charCodeAt(i);
+
+    if (extensionName === undefined) {
+      if (end === -1 && tokenChars[code] === 1) {
+        if (start === -1) start = i;
+      } else if (code === 0x20 /* ' ' */ || code === 0x09 /* '\t' */) {
+        if (end === -1 && start !== -1) end = i;
+      } else if (code === 0x3b /* ';' */ || code === 0x2c /* ',' */) {
+        if (start === -1) {
+          throw new SyntaxError(`Unexpected character at index ${i}`);
+        }
+
+        if (end === -1) end = i;
+        const name = header.slice(start, end);
+        if (code === 0x2c) {
+          push(offers, name, params);
+          params = Object.create(null);
+        } else {
+          extensionName = name;
+        }
+
+        start = end = -1;
+      } else {
+        throw new SyntaxError(`Unexpected character at index ${i}`);
+      }
+    } else if (paramName === undefined) {
+      if (end === -1 && tokenChars[code] === 1) {
+        if (start === -1) start = i;
+      } else if (code === 0x20 || code === 0x09) {
+        if (end === -1 && start !== -1) end = i;
+      } else if (code === 0x3b || code === 0x2c) {
+        if (start === -1) {
+          throw new SyntaxError(`Unexpected character at index ${i}`);
+        }
+
+        if (end === -1) end = i;
+        push(params, header.slice(start, end), true);
+        if (code === 0x2c) {
+          push(offers, extensionName, params);
+          params = Object.create(null);
+          extensionName = undefined;
+        }
+
+        start = end = -1;
+      } else if (code === 0x3d /* '=' */ && start !== -1 && end === -1) {
+        paramName = header.slice(start, i);
+        start = end = -1;
+      } else {
+        throw new SyntaxError(`Unexpected character at index ${i}`);
+      }
+    } else {
+      //
+      // The value of a quoted-string after unescaping must conform to the
+      // token ABNF, so only token characters are valid.
+      // Ref: https://tools.ietf.org/html/rfc6455#section-9.1
+      //
+      if (isEscaping) {
+        if (tokenChars[code] !== 1) {
+          throw new SyntaxError(`Unexpected character at index ${i}`);
+        }
+        if (start === -1) start = i;
+        else if (!mustUnescape) mustUnescape = true;
+        isEscaping = false;
+      } else if (inQuotes) {
+        if (tokenChars[code] === 1) {
+          if (start === -1) start = i;
+        } else if (code === 0x22 /* '"' */ && start !== -1) {
+          inQuotes = false;
+          end = i;
+        } else if (code === 0x5c /* '\' */) {
+          isEscaping = true;
+        } else {
+          throw new SyntaxError(`Unexpected character at index ${i}`);
+        }
+      } else if (code === 0x22 && header.charCodeAt(i - 1) === 0x3d) {
+        inQuotes = true;
+      } else if (end === -1 && tokenChars[code] === 1) {
+        if (start === -1) start = i;
+      } else if (start !== -1 && (code === 0x20 || code === 0x09)) {
+        if (end === -1) end = i;
+      } else if (code === 0x3b || code === 0x2c) {
+        if (start === -1) {
+          throw new SyntaxError(`Unexpected character at index ${i}`);
+        }
+
+        if (end === -1) end = i;
+        let value = header.slice(start, end);
+        if (mustUnescape) {
+          value = value.replace(/\\/g, '');
+          mustUnescape = false;
+        }
+        push(params, paramName, value);
+        if (code === 0x2c) {
+          push(offers, extensionName, params);
+          params = Object.create(null);
+          extensionName = undefined;
+        }
+
+        paramName = undefined;
+        start = end = -1;
+      } else {
+        throw new SyntaxError(`Unexpected character at index ${i}`);
+      }
+    }
+  }
+
+  if (start === -1 || inQuotes) {
+    throw new SyntaxError('Unexpected end of input');
+  }
+
+  if (end === -1) end = i;
+  const token = header.slice(start, end);
+  if (extensionName === undefined) {
+    push(offers, token, params);
+  } else {
+    if (paramName === undefined) {
+      push(params, token, true);
+    } else if (mustUnescape) {
+      push(params, paramName, token.replace(/\\/g, ''));
+    } else {
+      push(params, paramName, token);
+    }
+    push(offers, extensionName, params);
+  }
+
+  return offers;
+}
+
+/**
+ * Builds the `Sec-WebSocket-Extensions` header field value.
+ *
+ * @param {Object} extensions The map of extensions and parameters to format
+ * @return {String} A string representing the given object
+ * @public
+ */
+function format(extensions) {
+  return Object.keys(extensions)
+    .map((extension) => {
+      let configurations = extensions[extension];
+      if (!Array.isArray(configurations)) configurations = [configurations];
+      return configurations
+        .map((params) => {
+          return [extension]
+            .concat(
+              Object.keys(params).map((k) => {
+                let values = params[k];
+                if (!Array.isArray(values)) values = [values];
+                return values
+                  .map((v) => (v === true ? k : `${k}=${v}`))
+                  .join('; ');
+              })
+            )
+            .join('; ');
+        })
+        .join(', ');
+    })
+    .join(', ');
+}
+
+module.exports = { format, parse };
@@ -0,0 +1,54 @@
+'use strict';
+
+const kDone = Symbol('kDone');
+const kRun = Symbol('kRun');
+
+/**
+ * A very simple job queue with adjustable concurrency. Adapted from
+ * https://github.com/STRML/async-limiter
+ */
+class Limiter {
+  /**
+   * Creates a new `Limiter`.
+   *
+   * @param {Number} concurrency The maximum number of jobs allowed to run
+   *     concurrently
+   */
+  constructor(concurrency) {
+    this[kDone] = () => {
+      this.pending--;
+      this[kRun]();
+    };
+    this.concurrency = concurrency || Infinity;
+    this.jobs = [];
+    this.pending = 0;
+  }
+
+  /**
+   * Adds a job to the queue.
+   *
+   * @public
+   */
+  add(job) {
+    this.jobs.push(job);
+    this[kRun]();
+  }
+
+  /**
+   * Removes a job from the queue and runs it if possible.
+   *
+   * @private
+   */
+  [kRun]() {
+    if (this.pending === this.concurrency) return;
+
+    if (this.jobs.length) {
+      const job = this.jobs.shift();
+
+      this.pending++;
+      job(this[kDone]);
+    }
+  }
+}
+
+module.exports = Limiter;
@@ -0,0 +1,512 @@
+'use strict';
+
+const zlib = require('zlib');
+
+const bufferUtil = require('./buffer-util');
+const Limiter = require('./limiter');
+const { kStatusCode, NOOP } = require('./constants');
+
+const TRAILER = Buffer.from([0x00, 0x00, 0xff, 0xff]);
+const kPerMessageDeflate = Symbol('permessage-deflate');
+const kTotalLength = Symbol('total-length');
+const kCallback = Symbol('callback');
+const kBuffers = Symbol('buffers');
+const kError = Symbol('error');
+
+//
+// We limit zlib concurrency, which prevents severe memory fragmentation
+// as documented in https://github.com/nodejs/node/issues/8871#issuecomment-250915913
+// and https://github.com/websockets/ws/issues/1202
+//
+// Intentionally global; it's the global thread pool that's an issue.
+//
+let zlibLimiter;
+
+/**
+ * permessage-deflate implementation.
+ */
+class PerMessageDeflate {
+  /**
+   * Creates a PerMessageDeflate instance.
+   *
+   * @param {Object} options Configuration options
+   * @param {Boolean} options.serverNoContextTakeover Request/accept disabling
+   *     of server context takeover
+   * @param {Boolean} options.clientNoContextTakeover Advertise/acknowledge
+   *     disabling of client context takeover
+   * @param {(Boolean|Number)} options.serverMaxWindowBits Request/confirm the
+   *     use of a custom server window size
+   * @param {(Boolean|Number)} options.clientMaxWindowBits Advertise support
+   *     for, or request, a custom client window size
+   * @param {Object} options.zlibDeflateOptions Options to pass to zlib on deflate
+   * @param {Object} options.zlibInflateOptions Options to pass to zlib on inflate
+   * @param {Number} options.threshold Size (in bytes) below which messages
+   *     should not be compressed
+   * @param {Number} options.concurrencyLimit The number of concurrent calls to
+   *     zlib
+   * @param {Boolean} isServer Create the instance in either server or client
+   *     mode
+   * @param {Number} maxPayload The maximum allowed message length
+   */
+  constructor(options, isServer, maxPayload) {
+    this._maxPayload = maxPayload | 0;
+    this._options = options || {};
+    this._threshold =
+      this._options.threshold !== undefined ? this._options.threshold : 1024;
+    this._isServer = !!isServer;
+    this._deflate = null;
+    this._inflate = null;
+
+    this.params = null;
+
+    if (!zlibLimiter) {
+      const concurrency =
+        this._options.concurrencyLimit !== undefined
+          ? this._options.concurrencyLimit
+          : 10;
+      zlibLimiter = new Limiter(concurrency);
+    }
+  }
+
+  /**
+   * @type {String}
+   */
+  static get extensionName() {
+    return 'permessage-deflate';
+  }
+
+  /**
+   * Create an extension negotiation offer.
+   *
+   * @return {Object} Extension parameters
+   * @public
+   */
+  offer() {
+    const params = {};
+
+    if (this._options.serverNoContextTakeover) {
+      params.server_no_context_takeover = true;
+    }
+    if (this._options.clientNoContextTakeover) {
+      params.client_no_context_takeover = true;
+    }
+    if (this._options.serverMaxWindowBits) {
+      params.server_max_window_bits = this._options.serverMaxWindowBits;
+    }
+    if (this._options.clientMaxWindowBits) {
+      params.client_max_window_bits = this._options.clientMaxWindowBits;
+    } else if (this._options.clientMaxWindowBits == null) {
+      params.client_max_window_bits = true;
+    }
+
+    return params;
+  }
+
+  /**
+   * Accept an extension negotiation offer/response.
+   *
+   * @param {Array} configurations The extension negotiation offers/reponse
+   * @return {Object} Accepted configuration
+   * @public
+   */
+  accept(configurations) {
+    configurations = this.normalizeParams(configurations);
+
+    this.params = this._isServer
+      ? this.acceptAsServer(configurations)
+      : this.acceptAsClient(configurations);
+
+    return this.params;
+  }
+
+  /**
+   * Releases all resources used by the extension.
+   *
+   * @public
+   */
+  cleanup() {
+    if (this._inflate) {
+      this._inflate.close();
+      this._inflate = null;
+    }
+
+    if (this._deflate) {
+      const callback = this._deflate[kCallback];
+
+      this._deflate.close();
+      this._deflate = null;
+
+      if (callback) {
+        callback(
+          new Error(
+            'The deflate stream was closed while data was being processed'
+          )
+        );
+      }
+    }
+  }
+
+  /**
+   *  Accept an extension negotiation offer.
+   *
+   * @param {Array} offers The extension negotiation offers
+   * @return {Object} Accepted configuration
+   * @private
+   */
+  acceptAsServer(offers) {
+    const opts = this._options;
+    const accepted = offers.find((params) => {
+      if (
+        (opts.serverNoContextTakeover === false &&
+          params.server_no_context_takeover) ||
+        (params.server_max_window_bits &&
+          (opts.serverMaxWindowBits === false ||
+            (typeof opts.serverMaxWindowBits === 'number' &&
+              opts.serverMaxWindowBits > params.server_max_window_bits))) ||
+        (typeof opts.clientMaxWindowBits === 'number' &&
+          !params.client_max_window_bits)
+      ) {
+        return false;
+      }
+
+      return true;
+    });
+
+    if (!accepted) {
+      throw new Error('None of the extension offers can be accepted');
+    }
+
+    if (opts.serverNoContextTakeover) {
+      accepted.server_no_context_takeover = true;
+    }
+    if (opts.clientNoContextTakeover) {
+      accepted.client_no_context_takeover = true;
+    }
+    if (typeof opts.serverMaxWindowBits === 'number') {
+      accepted.server_max_window_bits = opts.serverMaxWindowBits;
+    }
+    if (typeof opts.clientMaxWindowBits === 'number') {
+      accepted.client_max_window_bits = opts.clientMaxWindowBits;
+    } else if (
+      accepted.client_max_window_bits === true ||
+      opts.clientMaxWindowBits === false
+    ) {
+      delete accepted.client_max_window_bits;
+    }
+
+    return accepted;
+  }
+
+  /**
+   * Accept the extension negotiation response.
+   *
+   * @param {Array} response The extension negotiation response
+   * @return {Object} Accepted configuration
+   * @private
+   */
+  acceptAsClient(response) {
+    const params = response[0];
+
+    if (
+      this._options.clientNoContextTakeover === false &&
+      params.client_no_context_takeover
+    ) {
+      throw new Error('Unexpected parameter "client_no_context_takeover"');
+    }
+
+    if (!params.client_max_window_bits) {
+      if (typeof this._options.clientMaxWindowBits === 'number') {
+        params.client_max_window_bits = this._options.clientMaxWindowBits;
+      }
+    } else if (
+      this._options.clientMaxWindowBits === false ||
+      (typeof this._options.clientMaxWindowBits === 'number' &&
+        params.client_max_window_bits > this._options.clientMaxWindowBits)
+    ) {
+      throw new Error(
+        'Unexpected or invalid parameter "client_max_window_bits"'
+      );
+    }
+
+    return params;
+  }
+
+  /**
+   * Normalize parameters.
+   *
+   * @param {Array} configurations The extension negotiation offers/reponse
+   * @return {Array} The offers/response with normalized parameters
+   * @private
+   */
+  normalizeParams(configurations) {
+    configurations.forEach((params) => {
+      Object.keys(params).forEach((key) => {
+        let value = params[key];
+
+        if (value.length > 1) {
+          throw new Error(`Parameter "${key}" must have only a single value`);
+        }
+
+        value = value[0];
+
+        if (key === 'client_max_window_bits') {
+          if (value !== true) {
+            const num = +value;
+            if (!Number.isInteger(num) || num < 8 || num > 15) {
+              throw new TypeError(
+                `Invalid value for parameter "${key}": ${value}`
+              );
+            }
+            value = num;
+          } else if (!this._isServer) {
+            throw new TypeError(
+              `Invalid value for parameter "${key}": ${value}`
+            );
+          }
+        } else if (key === 'server_max_window_bits') {
+          const num = +value;
+          if (!Number.isInteger(num) || num < 8 || num > 15) {
+            throw new TypeError(
+              `Invalid value for parameter "${key}": ${value}`
+            );
+          }
+          value = num;
+        } else if (
+          key === 'client_no_context_takeover' ||
+          key === 'server_no_context_takeover'
+        ) {
+          if (value !== true) {
+            throw new TypeError(
+              `Invalid value for parameter "${key}": ${value}`
+            );
+          }
+        } else {
+          throw new Error(`Unknown parameter "${key}"`);
+        }
+
+        params[key] = value;
+      });
+    });
+
+    return configurations;
+  }
+
+  /**
+   * Decompress data. Concurrency limited.
+   *
+   * @param {Buffer} data Compressed data
+   * @param {Boolean} fin Specifies whether or not this is the last fragment
+   * @param {Function} callback Callback
+   * @public
+   */
+  decompress(data, fin, callback) {
+    zlibLimiter.add((done) => {
+      this._decompress(data, fin, (err, result) => {
+        done();
+        callback(err, result);
+      });
+    });
+  }
+
+  /**
+   * Compress data. Concurrency limited.
+   *
+   * @param {Buffer} data Data to compress
+   * @param {Boolean} fin Specifies whether or not this is the last fragment
+   * @param {Function} callback Callback
+   * @public
+   */
+  compress(data, fin, callback) {
+    zlibLimiter.add((done) => {
+      this._compress(data, fin, (err, result) => {
+        done();
+        callback(err, result);
+      });
+    });
+  }
+
+  /**
+   * Decompress data.
+   *
+   * @param {Buffer} data Compressed data
+   * @param {Boolean} fin Specifies whether or not this is the last fragment
+   * @param {Function} callback Callback
+   * @private
+   */
+  _decompress(data, fin, callback) {
+    const endpoint = this._isServer ? 'client' : 'server';
+
+    if (!this._inflate) {
+      const key = `${endpoint}_max_window_bits`;
+      const windowBits =
+        typeof this.params[key] !== 'number'
+          ? zlib.Z_DEFAULT_WINDOWBITS
+          : this.params[key];
+
+      this._inflate = zlib.createInflateRaw({
+        ...this._options.zlibInflateOptions,
+        windowBits
+      });
+      this._inflate[kPerMessageDeflate] = this;
+      this._inflate[kTotalLength] = 0;
+      this._inflate[kBuffers] = [];
+      this._inflate.on('error', inflateOnError);
+      this._inflate.on('data', inflateOnData);
+    }
+
+    this._inflate[kCallback] = callback;
+
+    this._inflate.write(data);
+    if (fin) this._inflate.write(TRAILER);
+
+    this._inflate.flush(() => {
+      const err = this._inflate[kError];
+
+      if (err) {
+        this._inflate.close();
+        this._inflate = null;
+        callback(err);
+        return;
+      }
+
+      const data = bufferUtil.concat(
+        this._inflate[kBuffers],
+        this._inflate[kTotalLength]
+      );
+
+      if (fin && this.params[`${endpoint}_no_context_takeover`]) {
+        this._inflate.close();
+        this._inflate = null;
+      } else {
+        this._inflate[kTotalLength] = 0;
+        this._inflate[kBuffers] = [];
+      }
+
+      callback(null, data);
+    });
+  }
+
+  /**
+   * Compress data.
+   *
+   * @param {Buffer} data Data to compress
+   * @param {Boolean} fin Specifies whether or not this is the last fragment
+   * @param {Function} callback Callback
+   * @private
+   */
+  _compress(data, fin, callback) {
+    const endpoint = this._isServer ? 'server' : 'client';
+
+    if (!this._deflate) {
+      const key = `${endpoint}_max_window_bits`;
+      const windowBits =
+        typeof this.params[key] !== 'number'
+          ? zlib.Z_DEFAULT_WINDOWBITS
+          : this.params[key];
+
+      this._deflate = zlib.createDeflateRaw({
+        ...this._options.zlibDeflateOptions,
+        windowBits
+      });
+
+      this._deflate[kTotalLength] = 0;
+      this._deflate[kBuffers] = [];
+
+      //
+      // An `'error'` event is emitted, only on Node.js < 10.0.0, if the
+      // `zlib.DeflateRaw` instance is closed while data is being processed.
+      // This can happen if `PerMessageDeflate#cleanup()` is called at the wrong
+      // time due to an abnormal WebSocket closure.
+      //
+      this._deflate.on('error', NOOP);
+      this._deflate.on('data', deflateOnData);
+    }
+
+    this._deflate[kCallback] = callback;
+
+    this._deflate.write(data);
+    this._deflate.flush(zlib.Z_SYNC_FLUSH, () => {
+      if (!this._deflate) {
+        //
+        // The deflate stream was closed while data was being processed.
+        //
+        return;
+      }
+
+      let data = bufferUtil.concat(
+        this._deflate[kBuffers],
+        this._deflate[kTotalLength]
+      );
+
+      if (fin) data = data.slice(0, data.length - 4);
+
+      //
+      // Ensure that the callback will not be called again in
+      // `PerMessageDeflate#cleanup()`.
+      //
+      this._deflate[kCallback] = null;
+
+      if (fin && this.params[`${endpoint}_no_context_takeover`]) {
+        this._deflate.close();
+        this._deflate = null;
+      } else {
+        this._deflate[kTotalLength] = 0;
+        this._deflate[kBuffers] = [];
+      }
+
+      callback(null, data);
+    });
+  }
+}
+
+module.exports = PerMessageDeflate;
+
+/**
+ * The listener of the `zlib.DeflateRaw` stream `'data'` event.
+ *
+ * @param {Buffer} chunk A chunk of data
+ * @private
+ */
+function deflateOnData(chunk) {
+  this[kBuffers].push(chunk);
+  this[kTotalLength] += chunk.length;
+}
+
+/**
+ * The listener of the `zlib.InflateRaw` stream `'data'` event.
+ *
+ * @param {Buffer} chunk A chunk of data
+ * @private
+ */
+function inflateOnData(chunk) {
+  this[kTotalLength] += chunk.length;
+
+  if (
+    this[kPerMessageDeflate]._maxPayload < 1 ||
+    this[kTotalLength] <= this[kPerMessageDeflate]._maxPayload
+  ) {
+    this[kBuffers].push(chunk);
+    return;
+  }
+
+  this[kError] = new RangeError('Max payload size exceeded');
+  this[kError][kStatusCode] = 1009;
+  this.removeListener('data', inflateOnData);
+  this.reset();
+}
+
+/**
+ * The listener of the `zlib.InflateRaw` stream `'error'` event.
+ *
+ * @param {Error} err The emitted error
+ * @private
+ */
+function inflateOnError(err) {
+  //
+  // There is no need to call `Zlib#close()` as the handle is automatically
+  // closed when an error is emitted.
+  //
+  this[kPerMessageDeflate]._inflate = null;
+  err[kStatusCode] = 1007;
+  this[kCallback](err);
+}
@@ -0,0 +1,506 @@
+'use strict';
+
+const { Writable } = require('stream');
+
+const PerMessageDeflate = require('./permessage-deflate');
+const {
+  BINARY_TYPES,
+  EMPTY_BUFFER,
+  kStatusCode,
+  kWebSocket
+} = require('./constants');
+const { concat, toArrayBuffer, unmask } = require('./buffer-util');
+const { isValidStatusCode, isValidUTF8 } = require('./validation');
+
+const GET_INFO = 0;
+const GET_PAYLOAD_LENGTH_16 = 1;
+const GET_PAYLOAD_LENGTH_64 = 2;
+const GET_MASK = 3;
+const GET_DATA = 4;
+const INFLATING = 5;
+
+/**
+ * HyBi Receiver implementation.
+ *
+ * @extends stream.Writable
+ */
+class Receiver extends Writable {
+  /**
+   * Creates a Receiver instance.
+   *
+   * @param {String} binaryType The type for binary data
+   * @param {Object} extensions An object containing the negotiated extensions
+   * @param {Boolean} isServer Specifies whether to operate in client or server
+   *     mode
+   * @param {Number} maxPayload The maximum allowed message length
+   */
+  constructor(binaryType, extensions, isServer, maxPayload) {
+    super();
+
+    this._binaryType = binaryType || BINARY_TYPES[0];
+    this[kWebSocket] = undefined;
+    this._extensions = extensions || {};
+    this._isServer = !!isServer;
+    this._maxPayload = maxPayload | 0;
+
+    this._bufferedBytes = 0;
+    this._buffers = [];
+
+    this._compressed = false;
+    this._payloadLength = 0;
+    this._mask = undefined;
+    this._fragmented = 0;
+    this._masked = false;
+    this._fin = false;
+    this._opcode = 0;
+
+    this._totalPayloadLength = 0;
+    this._messageLength = 0;
+    this._fragments = [];
+
+    this._state = GET_INFO;
+    this._loop = false;
+  }
+
+  /**
+   * Implements `Writable.prototype._write()`.
+   *
+   * @param {Buffer} chunk The chunk of data to write
+   * @param {String} encoding The character encoding of `chunk`
+   * @param {Function} cb Callback
+   */
+  _write(chunk, encoding, cb) {
+    if (this._opcode === 0x08 && this._state == GET_INFO) return cb();
+
+    this._bufferedBytes += chunk.length;
+    this._buffers.push(chunk);
+    this.startLoop(cb);
+  }
+
+  /**
+   * Consumes `n` bytes from the buffered data.
+   *
+   * @param {Number} n The number of bytes to consume
+   * @return {Buffer} The consumed bytes
+   * @private
+   */
+  consume(n) {
+    this._bufferedBytes -= n;
+
+    if (n === this._buffers[0].length) return this._buffers.shift();
+
+    if (n < this._buffers[0].length) {
+      const buf = this._buffers[0];
+      this._buffers[0] = buf.slice(n);
+      return buf.slice(0, n);
+    }
+
+    const dst = Buffer.allocUnsafe(n);
+
+    do {
+      const buf = this._buffers[0];
+      const offset = dst.length - n;
+
+      if (n >= buf.length) {
+        dst.set(this._buffers.shift(), offset);
+      } else {
+        dst.set(new Uint8Array(buf.buffer, buf.byteOffset, n), offset);
+        this._buffers[0] = buf.slice(n);
+      }
+
+      n -= buf.length;
+    } while (n > 0);
+
+    return dst;
+  }
+
+  /**
+   * Starts the parsing loop.
+   *
+   * @param {Function} cb Callback
+   * @private
+   */
+  startLoop(cb) {
+    let err;
+    this._loop = true;
+
+    do {
+      switch (this._state) {
+        case GET_INFO:
+          err = this.getInfo();
+          break;
+        case GET_PAYLOAD_LENGTH_16:
+          err = this.getPayloadLength16();
+          break;
+        case GET_PAYLOAD_LENGTH_64:
+          err = this.getPayloadLength64();
+          break;
+        case GET_MASK:
+          this.getMask();
+          break;
+        case GET_DATA:
+          err = this.getData(cb);
+          break;
+        default:
+          // `INFLATING`
+          this._loop = false;
+          return;
+      }
+    } while (this._loop);
+
+    cb(err);
+  }
+
+  /**
+   * Reads the first two bytes of a frame.
+   *
+   * @return {(RangeError|undefined)} A possible error
+   * @private
+   */
+  getInfo() {
+    if (this._bufferedBytes < 2) {
+      this._loop = false;
+      return;
+    }
+
+    const buf = this.consume(2);
+
+    if ((buf[0] & 0x30) !== 0x00) {
+      this._loop = false;
+      return error(RangeError, 'RSV2 and RSV3 must be clear', true, 1002);
+    }
+
+    const compressed = (buf[0] & 0x40) === 0x40;
+
+    if (compressed && !this._extensions[PerMessageDeflate.extensionName]) {
+      this._loop = false;
+      return error(RangeError, 'RSV1 must be clear', true, 1002);
+    }
+
+    this._fin = (buf[0] & 0x80) === 0x80;
+    this._opcode = buf[0] & 0x0f;
+    this._payloadLength = buf[1] & 0x7f;
+
+    if (this._opcode === 0x00) {
+      if (compressed) {
+        this._loop = false;
+        return error(RangeError, 'RSV1 must be clear', true, 1002);
+      }
+
+      if (!this._fragmented) {
+        this._loop = false;
+        return error(RangeError, 'invalid opcode 0', true, 1002);
+      }
+
+      this._opcode = this._fragmented;
+    } else if (this._opcode === 0x01 || this._opcode === 0x02) {
+      if (this._fragmented) {
+        this._loop = false;
+        return error(RangeError, `invalid opcode ${this._opcode}`, true, 1002);
+      }
+
+      this._compressed = compressed;
+    } else if (this._opcode > 0x07 && this._opcode < 0x0b) {
+      if (!this._fin) {
+        this._loop = false;
+        return error(RangeError, 'FIN must be set', true, 1002);
+      }
+
+      if (compressed) {
+        this._loop = false;
+        return error(RangeError, 'RSV1 must be clear', true, 1002);
+      }
+
+      if (this._payloadLength > 0x7d) {
+        this._loop = false;
+        return error(
+          RangeError,
+          `invalid payload length ${this._payloadLength}`,
+          true,
+          1002
+        );
+      }
+    } else {
+      this._loop = false;
+      return error(RangeError, `invalid opcode ${this._opcode}`, true, 1002);
+    }
+
+    if (!this._fin && !this._fragmented) this._fragmented = this._opcode;
+    this._masked = (buf[1] & 0x80) === 0x80;
+
+    if (this._isServer) {
+      if (!this._masked) {
+        this._loop = false;
+        return error(RangeError, 'MASK must be set', true, 1002);
+      }
+    } else if (this._masked) {
+      this._loop = false;
+      return error(RangeError, 'MASK must be clear', true, 1002);
+    }
+
+    if (this._payloadLength === 126) this._state = GET_PAYLOAD_LENGTH_16;
+    else if (this._payloadLength === 127) this._state = GET_PAYLOAD_LENGTH_64;
+    else return this.haveLength();
+  }
+
+  /**
+   * Gets extended payload length (7+16).
+   *
+   * @return {(RangeError|undefined)} A possible error
+   * @private
+   */
+  getPayloadLength16() {
+    if (this._bufferedBytes < 2) {
+      this._loop = false;
+      return;
+    }
+
+    this._payloadLength = this.consume(2).readUInt16BE(0);
+    return this.haveLength();
+  }
+
+  /**
+   * Gets extended payload length (7+64).
+   *
+   * @return {(RangeError|undefined)} A possible error
+   * @private
+   */
+  getPayloadLength64() {
+    if (this._bufferedBytes < 8) {
+      this._loop = false;
+      return;
+    }
+
+    const buf = this.consume(8);
+    const num = buf.readUInt32BE(0);
+
+    //
+    // The maximum safe integer in JavaScript is 2^53 - 1. An error is returned
+    // if payload length is greater than this number.
+    //
+    if (num > Math.pow(2, 53 - 32) - 1) {
+      this._loop = false;
+      return error(
+        RangeError,
+        'Unsupported WebSocket frame: payload length > 2^53 - 1',
+        false,
+        1009
+      );
+    }
+
+    this._payloadLength = num * Math.pow(2, 32) + buf.readUInt32BE(4);
+    return this.haveLength();
+  }
+
+  /**
+   * Payload length has been read.
+   *
+   * @return {(RangeError|undefined)} A possible error
+   * @private
+   */
+  haveLength() {
+    if (this._payloadLength && this._opcode < 0x08) {
+      this._totalPayloadLength += this._payloadLength;
+      if (this._totalPayloadLength > this._maxPayload && this._maxPayload > 0) {
+        this._loop = false;
+        return error(RangeError, 'Max payload size exceeded', false, 1009);
+      }
+    }
+
+    if (this._masked) this._state = GET_MASK;
+    else this._state = GET_DATA;
+  }
+
+  /**
+   * Reads mask bytes.
+   *
+   * @private
+   */
+  getMask() {
+    if (this._bufferedBytes < 4) {
+      this._loop = false;
+      return;
+    }
+
+    this._mask = this.consume(4);
+    this._state = GET_DATA;
+  }
+
+  /**
+   * Reads data bytes.
+   *
+   * @param {Function} cb Callback
+   * @return {(Error|RangeError|undefined)} A possible error
+   * @private
+   */
+  getData(cb) {
+    let data = EMPTY_BUFFER;
+
+    if (this._payloadLength) {
+      if (this._bufferedBytes < this._payloadLength) {
+        this._loop = false;
+        return;
+      }
+
+      data = this.consume(this._payloadLength);
+      if (this._masked) unmask(data, this._mask);
+    }
+
+    if (this._opcode > 0x07) return this.controlMessage(data);
+
+    if (this._compressed) {
+      this._state = INFLATING;
+      this.decompress(data, cb);
+      return;
+    }
+
+    if (data.length) {
+      //
+      // This message is not compressed so its lenght is the sum of the payload
+      // length of all fragments.
+      //
+      this._messageLength = this._totalPayloadLength;
+      this._fragments.push(data);
+    }
+
+    return this.dataMessage();
+  }
+
+  /**
+   * Decompresses data.
+   *
+   * @param {Buffer} data Compressed data
+   * @param {Function} cb Callback
+   * @private
+   */
+  decompress(data, cb) {
+    const perMessageDeflate = this._extensions[PerMessageDeflate.extensionName];
+
+    perMessageDeflate.decompress(data, this._fin, (err, buf) => {
+      if (err) return cb(err);
+
+      if (buf.length) {
+        this._messageLength += buf.length;
+        if (this._messageLength > this._maxPayload && this._maxPayload > 0) {
+          return cb(
+            error(RangeError, 'Max payload size exceeded', false, 1009)
+          );
+        }
+
+        this._fragments.push(buf);
+      }
+
+      const er = this.dataMessage();
+      if (er) return cb(er);
+
+      this.startLoop(cb);
+    });
+  }
+
+  /**
+   * Handles a data message.
+   *
+   * @return {(Error|undefined)} A possible error
+   * @private
+   */
+  dataMessage() {
+    if (this._fin) {
+      const messageLength = this._messageLength;
+      const fragments = this._fragments;
+
+      this._totalPayloadLength = 0;
+      this._messageLength = 0;
+      this._fragmented = 0;
+      this._fragments = [];
+
+      if (this._opcode === 2) {
+        let data;
+
+        if (this._binaryType === 'nodebuffer') {
+          data = concat(fragments, messageLength);
+        } else if (this._binaryType === 'arraybuffer') {
+          data = toArrayBuffer(concat(fragments, messageLength));
+        } else {
+          data = fragments;
+        }
+
+        this.emit('message', data);
+      } else {
+        const buf = concat(fragments, messageLength);
+
+        if (!isValidUTF8(buf)) {
+          this._loop = false;
+          return error(Error, 'invalid UTF-8 sequence', true, 1007);
+        }
+
+        this.emit('message', buf.toString());
+      }
+    }
+
+    this._state = GET_INFO;
+  }
+
+  /**
+   * Handles a control message.
+   *
+   * @param {Buffer} data Data to handle
+   * @return {(Error|RangeError|undefined)} A possible error
+   * @private
+   */
+  controlMessage(data) {
+    if (this._opcode === 0x08) {
+      this._loop = false;
+
+      if (data.length === 0) {
+        this.emit('conclude', 1005, '');
+        this.end();
+      } else if (data.length === 1) {
+        return error(RangeError, 'invalid payload length 1', true, 1002);
+      } else {
+        const code = data.readUInt16BE(0);
+
+        if (!isValidStatusCode(code)) {
+          return error(RangeError, `invalid status code ${code}`, true, 1002);
+        }
+
+        const buf = data.slice(2);
+
+        if (!isValidUTF8(buf)) {
+          return error(Error, 'invalid UTF-8 sequence', true, 1007);
+        }
+
+        this.emit('conclude', code, buf.toString());
+        this.end();
+      }
+    } else if (this._opcode === 0x09) {
+      this.emit('ping', data);
+    } else {
+      this.emit('pong', data);
+    }
+
+    this._state = GET_INFO;
+  }
+}
+
+module.exports = Receiver;
+
+/**
+ * Builds an error object.
+ *
+ * @param {(Error|RangeError)} ErrorCtor The error constructor
+ * @param {String} message The error message
+ * @param {Boolean} prefix Specifies whether or not to add a default prefix to
+ *     `message`
+ * @param {Number} statusCode The status code
+ * @return {(Error|RangeError)} The error
+ * @private
+ */
+function error(ErrorCtor, message, prefix, statusCode) {
+  const err = new ErrorCtor(
+    prefix ? `Invalid WebSocket frame: ${message}` : message
+  );
+
+  Error.captureStackTrace(err, error);
+  err[kStatusCode] = statusCode;
+  return err;
+}
@@ -0,0 +1,390 @@
+'use strict';
+
+const { randomFillSync } = require('crypto');
+
+const PerMessageDeflate = require('./permessage-deflate');
+const { EMPTY_BUFFER } = require('./constants');
+const { isValidStatusCode } = require('./validation');
+const { mask: applyMask, toBuffer } = require('./buffer-util');
+
+const mask = Buffer.alloc(4);
+
+/**
+ * HyBi Sender implementation.
+ */
+class Sender {
+  /**
+   * Creates a Sender instance.
+   *
+   * @param {net.Socket} socket The connection socket
+   * @param {Object} extensions An object containing the negotiated extensions
+   */
+  constructor(socket, extensions) {
+    this._extensions = extensions || {};
+    this._socket = socket;
+
+    this._firstFragment = true;
+    this._compress = false;
+
+    this._bufferedBytes = 0;
+    this._deflating = false;
+    this._queue = [];
+  }
+
+  /**
+   * Frames a piece of data according to the HyBi WebSocket protocol.
+   *
+   * @param {Buffer} data The data to frame
+   * @param {Object} options Options object
+   * @param {Number} options.opcode The opcode
+   * @param {Boolean} options.readOnly Specifies whether `data` can be modified
+   * @param {Boolean} options.fin Specifies whether or not to set the FIN bit
+   * @param {Boolean} options.mask Specifies whether or not to mask `data`
+   * @param {Boolean} options.rsv1 Specifies whether or not to set the RSV1 bit
+   * @return {Buffer[]} The framed data as a list of `Buffer` instances
+   * @public
+   */
+  static frame(data, options) {
+    const merge = options.mask && options.readOnly;
+    let offset = options.mask ? 6 : 2;
+    let payloadLength = data.length;
+
+    if (data.length >= 65536) {
+      offset += 8;
+      payloadLength = 127;
+    } else if (data.length > 125) {
+      offset += 2;
+      payloadLength = 126;
+    }
+
+    const target = Buffer.allocUnsafe(merge ? data.length + offset : offset);
+
+    target[0] = options.fin ? options.opcode | 0x80 : options.opcode;
+    if (options.rsv1) target[0] |= 0x40;
+
+    target[1] = payloadLength;
+
+    if (payloadLength === 126) {
+      target.writeUInt16BE(data.length, 2);
+    } else if (payloadLength === 127) {
+      target.writeUInt32BE(0, 2);
+      target.writeUInt32BE(data.length, 6);
+    }
+
+    if (!options.mask) return [target, data];
+
+    randomFillSync(mask, 0, 4);
+
+    target[1] |= 0x80;
+    target[offset - 4] = mask[0];
+    target[offset - 3] = mask[1];
+    target[offset - 2] = mask[2];
+    target[offset - 1] = mask[3];
+
+    if (merge) {
+      applyMask(data, mask, target, offset, data.length);
+      return [target];
+    }
+
+    applyMask(data, mask, data, 0, data.length);
+    return [target, data];
+  }
+
+  /**
+   * Sends a close message to the other peer.
+   *
+   * @param {(Number|undefined)} code The status code component of the body
+   * @param {String} data The message component of the body
+   * @param {Boolean} mask Specifies whether or not to mask the message
+   * @param {Function} cb Callback
+   * @public
+   */
+  close(code, data, mask, cb) {
+    let buf;
+
+    if (code === undefined) {
+      buf = EMPTY_BUFFER;
+    } else if (typeof code !== 'number' || !isValidStatusCode(code)) {
+      throw new TypeError('First argument must be a valid error code number');
+    } else if (data === undefined || data === '') {
+      buf = Buffer.allocUnsafe(2);
+      buf.writeUInt16BE(code, 0);
+    } else {
+      const length = Buffer.byteLength(data);
+
+      if (length > 123) {
+        throw new RangeError('The message must not be greater than 123 bytes');
+      }
+
+      buf = Buffer.allocUnsafe(2 + length);
+      buf.writeUInt16BE(code, 0);
+      buf.write(data, 2);
+    }
+
+    if (this._deflating) {
+      this.enqueue([this.doClose, buf, mask, cb]);
+    } else {
+      this.doClose(buf, mask, cb);
+    }
+  }
+
+  /**
+   * Frames and sends a close message.
+   *
+   * @param {Buffer} data The message to send
+   * @param {Boolean} mask Specifies whether or not to mask `data`
+   * @param {Function} cb Callback
+   * @private
+   */
+  doClose(data, mask, cb) {
+    this.sendFrame(
+      Sender.frame(data, {
+        fin: true,
+        rsv1: false,
+        opcode: 0x08,
+        mask,
+        readOnly: false
+      }),
+      cb
+    );
+  }
+
+  /**
+   * Sends a ping message to the other peer.
+   *
+   * @param {*} data The message to send
+   * @param {Boolean} mask Specifies whether or not to mask `data`
+   * @param {Function} cb Callback
+   * @public
+   */
+  ping(data, mask, cb) {
+    const buf = toBuffer(data);
+
+    if (buf.length > 125) {
+      throw new RangeError('The data size must not be greater than 125 bytes');
+    }
+
+    if (this._deflating) {
+      this.enqueue([this.doPing, buf, mask, toBuffer.readOnly, cb]);
+    } else {
+      this.doPing(buf, mask, toBuffer.readOnly, cb);
+    }
+  }
+
+  /**
+   * Frames and sends a ping message.
+   *
+   * @param {*} data The message to send
+   * @param {Boolean} mask Specifies whether or not to mask `data`
+   * @param {Boolean} readOnly Specifies whether `data` can be modified
+   * @param {Function} cb Callback
+   * @private
+   */
+  doPing(data, mask, readOnly, cb) {
+    this.sendFrame(
+      Sender.frame(data, {
+        fin: true,
+        rsv1: false,
+        opcode: 0x09,
+        mask,
+        readOnly
+      }),
+      cb
+    );
+  }
+
+  /**
+   * Sends a pong message to the other peer.
+   *
+   * @param {*} data The message to send
+   * @param {Boolean} mask Specifies whether or not to mask `data`
+   * @param {Function} cb Callback
+   * @public
+   */
+  pong(data, mask, cb) {
+    const buf = toBuffer(data);
+
+    if (buf.length > 125) {
+      throw new RangeError('The data size must not be greater than 125 bytes');
+    }
+
+    if (this._deflating) {
+      this.enqueue([this.doPong, buf, mask, toBuffer.readOnly, cb]);
+    } else {
+      this.doPong(buf, mask, toBuffer.readOnly, cb);
+    }
+  }
+
+  /**
+   * Frames and sends a pong message.
+   *
+   * @param {*} data The message to send
+   * @param {Boolean} mask Specifies whether or not to mask `data`
+   * @param {Boolean} readOnly Specifies whether `data` can be modified
+   * @param {Function} cb Callback
+   * @private
+   */
+  doPong(data, mask, readOnly, cb) {
+    this.sendFrame(
+      Sender.frame(data, {
+        fin: true,
+        rsv1: false,
+        opcode: 0x0a,
+        mask,
+        readOnly
+      }),
+      cb
+    );
+  }
+
+  /**
+   * Sends a data message to the other peer.
+   *
+   * @param {*} data The message to send
+   * @param {Object} options Options object
+   * @param {Boolean} options.compress Specifies whether or not to compress `data`
+   * @param {Boolean} options.binary Specifies whether `data` is binary or text
+   * @param {Boolean} options.fin Specifies whether the fragment is the last one
+   * @param {Boolean} options.mask Specifies whether or not to mask `data`
+   * @param {Function} cb Callback
+   * @public
+   */
+  send(data, options, cb) {
+    const buf = toBuffer(data);
+    const perMessageDeflate = this._extensions[PerMessageDeflate.extensionName];
+    let opcode = options.binary ? 2 : 1;
+    let rsv1 = options.compress;
+
+    if (this._firstFragment) {
+      this._firstFragment = false;
+      if (rsv1 && perMessageDeflate) {
+        rsv1 = buf.length >= perMessageDeflate._threshold;
+      }
+      this._compress = rsv1;
+    } else {
+      rsv1 = false;
+      opcode = 0;
+    }
+
+    if (options.fin) this._firstFragment = true;
+
+    if (perMessageDeflate) {
+      const opts = {
+        fin: options.fin,
+        rsv1,
+        opcode,
+        mask: options.mask,
+        readOnly: toBuffer.readOnly
+      };
+
+      if (this._deflating) {
+        this.enqueue([this.dispatch, buf, this._compress, opts, cb]);
+      } else {
+        this.dispatch(buf, this._compress, opts, cb);
+      }
+    } else {
+      this.sendFrame(
+        Sender.frame(buf, {
+          fin: options.fin,
+          rsv1: false,
+          opcode,
+          mask: options.mask,
+          readOnly: toBuffer.readOnly
+        }),
+        cb
+      );
+    }
+  }
+
+  /**
+   * Dispatches a data message.
+   *
+   * @param {Buffer} data The message to send
+   * @param {Boolean} compress Specifies whether or not to compress `data`
+   * @param {Object} options Options object
+   * @param {Number} options.opcode The opcode
+   * @param {Boolean} options.readOnly Specifies whether `data` can be modified
+   * @param {Boolean} options.fin Specifies whether or not to set the FIN bit
+   * @param {Boolean} options.mask Specifies whether or not to mask `data`
+   * @param {Boolean} options.rsv1 Specifies whether or not to set the RSV1 bit
+   * @param {Function} cb Callback
+   * @private
+   */
+  dispatch(data, compress, options, cb) {
+    if (!compress) {
+      this.sendFrame(Sender.frame(data, options), cb);
+      return;
+    }
+
+    const perMessageDeflate = this._extensions[PerMessageDeflate.extensionName];
+
+    this._deflating = true;
+    perMessageDeflate.compress(data, options.fin, (_, buf) => {
+      if (this._socket.destroyed) {
+        const err = new Error(
+          'The socket was closed while data was being compressed'
+        );
+
+        if (typeof cb === 'function') cb(err);
+
+        for (let i = 0; i < this._queue.length; i++) {
+          const callback = this._queue[i][4];
+
+          if (typeof callback === 'function') callback(err);
+        }
+
+        return;
+      }
+
+      this._deflating = false;
+      options.readOnly = false;
+      this.sendFrame(Sender.frame(buf, options), cb);
+      this.dequeue();
+    });
+  }
+
+  /**
+   * Executes queued send operations.
+   *
+   * @private
+   */
+  dequeue() {
+    while (!this._deflating && this._queue.length) {
+      const params = this._queue.shift();
+
+      this._bufferedBytes -= params[1].length;
+      Reflect.apply(params[0], this, params.slice(1));
+    }
+  }
+
+  /**
+   * Enqueues a send operation.
+   *
+   * @param {Array} params Send operation parameters.
+   * @private
+   */
+  enqueue(params) {
+    this._bufferedBytes += params[1].length;
+    this._queue.push(params);
+  }
+
+  /**
+   * Sends a frame.
+   *
+   * @param {Buffer[]} list The frame to send
+   * @param {Function} cb Callback
+   * @private
+   */
+  sendFrame(list, cb) {
+    if (list.length === 2) {
+      this._socket.cork();
+      this._socket.write(list[0]);
+      this._socket.write(list[1], cb);
+      this._socket.uncork();
+    } else {
+      this._socket.write(list[0], cb);
+    }
+  }
+}
+
+module.exports = Sender;
@@ -0,0 +1,164 @@
+'use strict';
+
+const { Duplex } = require('stream');
+
+/**
+ * Emits the `'close'` event on a stream.
+ *
+ * @param {stream.Duplex} The stream.
+ * @private
+ */
+function emitClose(stream) {
+  stream.emit('close');
+}
+
+/**
+ * The listener of the `'end'` event.
+ *
+ * @private
+ */
+function duplexOnEnd() {
+  if (!this.destroyed && this._writableState.finished) {
+    this.destroy();
+  }
+}
+
+/**
+ * The listener of the `'error'` event.
+ *
+ * @private
+ */
+function duplexOnError(err) {
+  this.removeListener('error', duplexOnError);
+  this.destroy();
+  if (this.listenerCount('error') === 0) {
+    // Do not suppress the throwing behavior.
+    this.emit('error', err);
+  }
+}
+
+/**
+ * Wraps a `WebSocket` in a duplex stream.
+ *
+ * @param {WebSocket} ws The `WebSocket` to wrap
+ * @param {Object} options The options for the `Duplex` constructor
+ * @return {stream.Duplex} The duplex stream
+ * @public
+ */
+function createWebSocketStream(ws, options) {
+  let resumeOnReceiverDrain = true;
+
+  function receiverOnDrain() {
+    if (resumeOnReceiverDrain) ws._socket.resume();
+  }
+
+  if (ws.readyState === ws.CONNECTING) {
+    ws.once('open', function open() {
+      ws._receiver.removeAllListeners('drain');
+      ws._receiver.on('drain', receiverOnDrain);
+    });
+  } else {
+    ws._receiver.removeAllListeners('drain');
+    ws._receiver.on('drain', receiverOnDrain);
+  }
+
+  const duplex = new Duplex({
+    ...options,
+    autoDestroy: false,
+    emitClose: false,
+    objectMode: false,
+    writableObjectMode: false
+  });
+
+  ws.on('message', function message(msg) {
+    if (!duplex.push(msg)) {
+      resumeOnReceiverDrain = false;
+      ws._socket.pause();
+    }
+  });
+
+  ws.once('error', function error(err) {
+    if (duplex.destroyed) return;
+
+    duplex.destroy(err);
+  });
+
+  ws.once('close', function close() {
+    if (duplex.destroyed) return;
+
+    duplex.push(null);
+  });
+
+  duplex._destroy = function(err, callback) {
+    if (ws.readyState === ws.CLOSED) {
+      callback(err);
+      process.nextTick(emitClose, duplex);
+      return;
+    }
+
+    let called = false;
+
+    ws.once('error', function error(err) {
+      called = true;
+      callback(err);
+    });
+
+    ws.once('close', function close() {
+      if (!called) callback(err);
+      process.nextTick(emitClose, duplex);
+    });
+    ws.terminate();
+  };
+
+  duplex._final = function(callback) {
+    if (ws.readyState === ws.CONNECTING) {
+      ws.once('open', function open() {
+        duplex._final(callback);
+      });
+      return;
+    }
+
+    // If the value of the `_socket` property is `null` it means that `ws` is a
+    // client websocket and the handshake failed. In fact, when this happens, a
+    // socket is never assigned to the websocket. Wait for the `'error'` event
+    // that will be emitted by the websocket.
+    if (ws._socket === null) return;
+
+    if (ws._socket._writableState.finished) {
+      if (duplex._readableState.endEmitted) duplex.destroy();
+      callback();
+    } else {
+      ws._socket.once('finish', function finish() {
+        // `duplex` is not destroyed here because the `'end'` event will be
+        // emitted on `duplex` after this `'finish'` event. The EOF signaling
+        // `null` chunk is, in fact, pushed when the websocket emits `'close'`.
+        callback();
+      });
+      ws.close();
+    }
+  };
+
+  duplex._read = function() {
+    if (ws.readyState === ws.OPEN && !resumeOnReceiverDrain) {
+      resumeOnReceiverDrain = true;
+      if (!ws._receiver._writableState.needDrain) ws._socket.resume();
+    }
+  };
+
+  duplex._write = function(chunk, encoding, callback) {
+    if (ws.readyState === ws.CONNECTING) {
+      ws.once('open', function open() {
+        duplex._write(chunk, encoding, callback);
+      });
+      return;
+    }
+
+    ws.send(chunk, callback);
+  };
+
+  duplex.on('end', duplexOnEnd);
+  duplex.on('error', duplexOnError);
+  return duplex;
+}
+
+module.exports = createWebSocketStream;
@@ -0,0 +1,30 @@
+'use strict';
+
+try {
+  const isValidUTF8 = require('utf-8-validate');
+
+  exports.isValidUTF8 =
+    typeof isValidUTF8 === 'object'
+      ? isValidUTF8.Validation.isValidUTF8 // utf-8-validate@<3.0.0
+      : isValidUTF8;
+} catch (e) /* istanbul ignore next */ {
+  exports.isValidUTF8 = () => true;
+}
+
+/**
+ * Checks if a status code is allowed in a close frame.
+ *
+ * @param {Number} code The status code
+ * @return {Boolean} `true` if the status code is valid, else `false`
+ * @public
+ */
+exports.isValidStatusCode = (code) => {
+  return (
+    (code >= 1000 &&
+      code <= 1014 &&
+      code !== 1004 &&
+      code !== 1005 &&
+      code !== 1006) ||
+    (code >= 3000 && code <= 4999)
+  );
+};
@@ -0,0 +1,406 @@
+'use strict';
+
+const EventEmitter = require('events');
+const { createHash } = require('crypto');
+const { createServer, STATUS_CODES } = require('http');
+
+const PerMessageDeflate = require('./permessage-deflate');
+const WebSocket = require('./websocket');
+const { format, parse } = require('./extension');
+const { GUID } = require('./constants');
+
+const keyRegex = /^[+/0-9A-Za-z]{22}==$/;
+const kUsedByWebSocketServer = Symbol('kUsedByWebSocketServer');
+
+/**
+ * Class representing a WebSocket server.
+ *
+ * @extends EventEmitter
+ */
+class WebSocketServer extends EventEmitter {
+  /**
+   * Create a `WebSocketServer` instance.
+   *
+   * @param {Object} options Configuration options
+   * @param {Number} options.backlog The maximum length of the queue of pending
+   *     connections
+   * @param {Boolean} options.clientTracking Specifies whether or not to track
+   *     clients
+   * @param {Function} options.handleProtocols A hook to handle protocols
+   * @param {String} options.host The hostname where to bind the server
+   * @param {Number} options.maxPayload The maximum allowed message size
+   * @param {Boolean} options.noServer Enable no server mode
+   * @param {String} options.path Accept only connections matching this path
+   * @param {(Boolean|Object)} options.perMessageDeflate Enable/disable
+   *     permessage-deflate
+   * @param {Number} options.port The port where to bind the server
+   * @param {http.Server} options.server A pre-created HTTP/S server to use
+   * @param {Function} options.verifyClient A hook to reject connections
+   * @param {Function} callback A listener for the `listening` event
+   */
+  constructor(options, callback) {
+    super();
+
+    options = {
+      maxPayload: 100 * 1024 * 1024,
+      perMessageDeflate: false,
+      handleProtocols: null,
+      clientTracking: true,
+      verifyClient: null,
+      noServer: false,
+      backlog: null, // use default (511 as implemented in net.js)
+      server: null,
+      host: null,
+      path: null,
+      port: null,
+      ...options
+    };
+
+    if (options.port == null && !options.server && !options.noServer) {
+      throw new TypeError(
+        'One of the "port", "server", or "noServer" options must be specified'
+      );
+    }
+
+    if (options.port != null) {
+      this._server = createServer((req, res) => {
+        const body = STATUS_CODES[426];
+
+        res.writeHead(426, {
+          'Content-Length': body.length,
+          'Content-Type': 'text/plain'
+        });
+        res.end(body);
+      });
+      this._server.listen(
+        options.port,
+        options.host,
+        options.backlog,
+        callback
+      );
+    } else if (options.server) {
+      if (options.server[kUsedByWebSocketServer]) {
+        throw new Error(
+          'The HTTP/S server is already being used by another WebSocket server'
+        );
+      }
+
+      options.server[kUsedByWebSocketServer] = true;
+      this._server = options.server;
+    }
+
+    if (this._server) {
+      this._removeListeners = addListeners(this._server, {
+        listening: this.emit.bind(this, 'listening'),
+        error: this.emit.bind(this, 'error'),
+        upgrade: (req, socket, head) => {
+          this.handleUpgrade(req, socket, head, (ws) => {
+            this.emit('connection', ws, req);
+          });
+        }
+      });
+    }
+
+    if (options.perMessageDeflate === true) options.perMessageDeflate = {};
+    if (options.clientTracking) this.clients = new Set();
+    this.options = options;
+  }
+
+  /**
+   * Returns the bound address, the address family name, and port of the server
+   * as reported by the operating system if listening on an IP socket.
+   * If the server is listening on a pipe or UNIX domain socket, the name is
+   * returned as a string.
+   *
+   * @return {(Object|String|null)} The address of the server
+   * @public
+   */
+  address() {
+    if (this.options.noServer) {
+      throw new Error('The server is operating in "noServer" mode');
+    }
+
+    if (!this._server) return null;
+    return this._server.address();
+  }
+
+  /**
+   * Close the server.
+   *
+   * @param {Function} cb Callback
+   * @public
+   */
+  close(cb) {
+    if (cb) this.once('close', cb);
+
+    //
+    // Terminate all associated clients.
+    //
+    if (this.clients) {
+      for (const client of this.clients) client.terminate();
+    }
+
+    const server = this._server;
+
+    if (server) {
+      this._removeListeners();
+      this._removeListeners = this._server = null;
+
+      //
+      // Close the http server if it was internally created.
+      //
+      if (this.options.port != null) {
+        server.close(() => this.emit('close'));
+        return;
+      }
+
+      delete server[kUsedByWebSocketServer];
+    }
+
+    process.nextTick(emitClose, this);
+  }
+
+  /**
+   * See if a given request should be handled by this server instance.
+   *
+   * @param {http.IncomingMessage} req Request object to inspect
+   * @return {Boolean} `true` if the request is valid, else `false`
+   * @public
+   */
+  shouldHandle(req) {
+    if (this.options.path) {
+      const index = req.url.indexOf('?');
+      const pathname = index !== -1 ? req.url.slice(0, index) : req.url;
+
+      if (pathname !== this.options.path) return false;
+    }
+
+    return true;
+  }
+
+  /**
+   * Handle a HTTP Upgrade request.
+   *
+   * @param {http.IncomingMessage} req The request object
+   * @param {net.Socket} socket The network socket between the server and client
+   * @param {Buffer} head The first packet of the upgraded stream
+   * @param {Function} cb Callback
+   * @public
+   */
+  handleUpgrade(req, socket, head, cb) {
+    socket.on('error', socketOnError);
+
+    const key =
+      req.headers['sec-websocket-key'] !== undefined
+        ? req.headers['sec-websocket-key'].trim()
+        : false;
+    const version = +req.headers['sec-websocket-version'];
+    const extensions = {};
+
+    if (
+      req.method !== 'GET' ||
+      req.headers.upgrade.toLowerCase() !== 'websocket' ||
+      !key ||
+      !keyRegex.test(key) ||
+      (version !== 8 && version !== 13) ||
+      !this.shouldHandle(req)
+    ) {
+      return abortHandshake(socket, 400);
+    }
+
+    if (this.options.perMessageDeflate) {
+      const perMessageDeflate = new PerMessageDeflate(
+        this.options.perMessageDeflate,
+        true,
+        this.options.maxPayload
+      );
+
+      try {
+        const offers = parse(req.headers['sec-websocket-extensions']);
+
+        if (offers[PerMessageDeflate.extensionName]) {
+          perMessageDeflate.accept(offers[PerMessageDeflate.extensionName]);
+          extensions[PerMessageDeflate.extensionName] = perMessageDeflate;
+        }
+      } catch (err) {
+        return abortHandshake(socket, 400);
+      }
+    }
+
+    //
+    // Optionally call external client verification handler.
+    //
+    if (this.options.verifyClient) {
+      const info = {
+        origin:
+          req.headers[`${version === 8 ? 'sec-websocket-origin' : 'origin'}`],
+        secure: !!(req.connection.authorized || req.connection.encrypted),
+        req
+      };
+
+      if (this.options.verifyClient.length === 2) {
+        this.options.verifyClient(info, (verified, code, message, headers) => {
+          if (!verified) {
+            return abortHandshake(socket, code || 401, message, headers);
+          }
+
+          this.completeUpgrade(key, extensions, req, socket, head, cb);
+        });
+        return;
+      }
+
+      if (!this.options.verifyClient(info)) return abortHandshake(socket, 401);
+    }
+
+    this.completeUpgrade(key, extensions, req, socket, head, cb);
+  }
+
+  /**
+   * Upgrade the connection to WebSocket.
+   *
+   * @param {String} key The value of the `Sec-WebSocket-Key` header
+   * @param {Object} extensions The accepted extensions
+   * @param {http.IncomingMessage} req The request object
+   * @param {net.Socket} socket The network socket between the server and client
+   * @param {Buffer} head The first packet of the upgraded stream
+   * @param {Function} cb Callback
+   * @private
+   */
+  completeUpgrade(key, extensions, req, socket, head, cb) {
+    //
+    // Destroy the socket if the client has already sent a FIN packet.
+    //
+    if (!socket.readable || !socket.writable) return socket.destroy();
+
+    const digest = createHash('sha1')
+      .update(key + GUID)
+      .digest('base64');
+
+    const headers = [
+      'HTTP/1.1 101 Switching Protocols',
+      'Upgrade: websocket',
+      'Connection: Upgrade',
+      `Sec-WebSocket-Accept: ${digest}`
+    ];
+
+    const ws = new WebSocket(null);
+    let protocol = req.headers['sec-websocket-protocol'];
+
+    if (protocol) {
+      protocol = protocol.trim().split(/ *, */);
+
+      //
+      // Optionally call external protocol selection handler.
+      //
+      if (this.options.handleProtocols) {
+        protocol = this.options.handleProtocols(protocol, req);
+      } else {
+        protocol = protocol[0];
+      }
+
+      if (protocol) {
+        headers.push(`Sec-WebSocket-Protocol: ${protocol}`);
+        ws.protocol = protocol;
+      }
+    }
+
+    if (extensions[PerMessageDeflate.extensionName]) {
+      const params = extensions[PerMessageDeflate.extensionName].params;
+      const value = format({
+        [PerMessageDeflate.extensionName]: [params]
+      });
+      headers.push(`Sec-WebSocket-Extensions: ${value}`);
+      ws._extensions = extensions;
+    }
+
+    //
+    // Allow external modification/inspection of handshake headers.
+    //
+    this.emit('headers', headers, req);
+
+    socket.write(headers.concat('\r\n').join('\r\n'));
+    socket.removeListener('error', socketOnError);
+
+    ws.setSocket(socket, head, this.options.maxPayload);
+
+    if (this.clients) {
+      this.clients.add(ws);
+      ws.on('close', () => this.clients.delete(ws));
+    }
+
+    cb(ws);
+  }
+}
+
+module.exports = WebSocketServer;
+
+/**
+ * Add event listeners on an `EventEmitter` using a map of <event, listener>
+ * pairs.
+ *
+ * @param {EventEmitter} server The event emitter
+ * @param {Object.<String, Function>} map The listeners to add
+ * @return {Function} A function that will remove the added listeners when called
+ * @private
+ */
+function addListeners(server, map) {
+  for (const event of Object.keys(map)) server.on(event, map[event]);
+
+  return function removeListeners() {
+    for (const event of Object.keys(map)) {
+      server.removeListener(event, map[event]);
+    }
+  };
+}
+
+/**
+ * Emit a `'close'` event on an `EventEmitter`.
+ *
+ * @param {EventEmitter} server The event emitter
+ * @private
+ */
+function emitClose(server) {
+  server.emit('close');
+}
+
+/**
+ * Handle premature socket errors.
+ *
+ * @private
+ */
+function socketOnError() {
+  this.destroy();
+}
+
+/**
+ * Close the connection when preconditions are not fulfilled.
+ *
+ * @param {net.Socket} socket The socket of the upgrade request
+ * @param {Number} code The HTTP response status code
+ * @param {String} [message] The HTTP response body
+ * @param {Object} [headers] Additional HTTP response headers
+ * @private
+ */
+function abortHandshake(socket, code, message, headers) {
+  if (socket.writable) {
+    message = message || STATUS_CODES[code];
+    headers = {
+      Connection: 'close',
+      'Content-type': 'text/html',
+      'Content-Length': Buffer.byteLength(message),
+      ...headers
+    };
+
+    socket.write(
+      `HTTP/1.1 ${code} ${STATUS_CODES[code]}\r\n` +
+        Object.keys(headers)
+          .map((h) => `${h}: ${headers[h]}`)
+          .join('\r\n') +
+        '\r\n\r\n' +
+        message
+    );
+  }
+
+  socket.removeListener('error', socketOnError);
+  socket.destroy();
+}
@@ -0,0 +1,909 @@
+'use strict';
+
+const EventEmitter = require('events');
+const https = require('https');
+const http = require('http');
+const net = require('net');
+const tls = require('tls');
+const { randomBytes, createHash } = require('crypto');
+const { URL } = require('url');
+
+const PerMessageDeflate = require('./permessage-deflate');
+const Receiver = require('./receiver');
+const Sender = require('./sender');
+const {
+  BINARY_TYPES,
+  EMPTY_BUFFER,
+  GUID,
+  kStatusCode,
+  kWebSocket,
+  NOOP
+} = require('./constants');
+const { addEventListener, removeEventListener } = require('./event-target');
+const { format, parse } = require('./extension');
+const { toBuffer } = require('./buffer-util');
+
+const readyStates = ['CONNECTING', 'OPEN', 'CLOSING', 'CLOSED'];
+const protocolVersions = [8, 13];
+const closeTimeout = 30 * 1000;
+
+/**
+ * Class representing a WebSocket.
+ *
+ * @extends EventEmitter
+ */
+class WebSocket extends EventEmitter {
+  /**
+   * Create a new `WebSocket`.
+   *
+   * @param {(String|url.URL)} address The URL to which to connect
+   * @param {(String|String[])} protocols The subprotocols
+   * @param {Object} options Connection options
+   */
+  constructor(address, protocols, options) {
+    super();
+
+    this.readyState = WebSocket.CONNECTING;
+    this.protocol = '';
+
+    this._binaryType = BINARY_TYPES[0];
+    this._closeFrameReceived = false;
+    this._closeFrameSent = false;
+    this._closeMessage = '';
+    this._closeTimer = null;
+    this._closeCode = 1006;
+    this._extensions = {};
+    this._receiver = null;
+    this._sender = null;
+    this._socket = null;
+
+    if (address !== null) {
+      this._bufferedAmount = 0;
+      this._isServer = false;
+      this._redirects = 0;
+
+      if (Array.isArray(protocols)) {
+        protocols = protocols.join(', ');
+      } else if (typeof protocols === 'object' && protocols !== null) {
+        options = protocols;
+        protocols = undefined;
+      }
+
+      initAsClient(this, address, protocols, options);
+    } else {
+      this._isServer = true;
+    }
+  }
+
+  get CONNECTING() {
+    return WebSocket.CONNECTING;
+  }
+  get CLOSING() {
+    return WebSocket.CLOSING;
+  }
+  get CLOSED() {
+    return WebSocket.CLOSED;
+  }
+  get OPEN() {
+    return WebSocket.OPEN;
+  }
+
+  /**
+   * This deviates from the WHATWG interface since ws doesn't support the
+   * required default "blob" type (instead we define a custom "nodebuffer"
+   * type).
+   *
+   * @type {String}
+   */
+  get binaryType() {
+    return this._binaryType;
+  }
+
+  set binaryType(type) {
+    if (!BINARY_TYPES.includes(type)) return;
+
+    this._binaryType = type;
+
+    //
+    // Allow to change `binaryType` on the fly.
+    //
+    if (this._receiver) this._receiver._binaryType = type;
+  }
+
+  /**
+   * @type {Number}
+   */
+  get bufferedAmount() {
+    if (!this._socket) return this._bufferedAmount;
+
+    //
+    // `socket.bufferSize` is `undefined` if the socket is closed.
+    //
+    return (this._socket.bufferSize || 0) + this._sender._bufferedBytes;
+  }
+
+  /**
+   * @type {String}
+   */
+  get extensions() {
+    return Object.keys(this._extensions).join();
+  }
+
+  /**
+   * Set up the socket and the internal resources.
+   *
+   * @param {net.Socket} socket The network socket between the server and client
+   * @param {Buffer} head The first packet of the upgraded stream
+   * @param {Number} maxPayload The maximum allowed message size
+   * @private
+   */
+  setSocket(socket, head, maxPayload) {
+    const receiver = new Receiver(
+      this._binaryType,
+      this._extensions,
+      this._isServer,
+      maxPayload
+    );
+
+    this._sender = new Sender(socket, this._extensions);
+    this._receiver = receiver;
+    this._socket = socket;
+
+    receiver[kWebSocket] = this;
+    socket[kWebSocket] = this;
+
+    receiver.on('conclude', receiverOnConclude);
+    receiver.on('drain', receiverOnDrain);
+    receiver.on('error', receiverOnError);
+    receiver.on('message', receiverOnMessage);
+    receiver.on('ping', receiverOnPing);
+    receiver.on('pong', receiverOnPong);
+
+    socket.setTimeout(0);
+    socket.setNoDelay();
+
+    if (head.length > 0) socket.unshift(head);
+
+    socket.on('close', socketOnClose);
+    socket.on('data', socketOnData);
+    socket.on('end', socketOnEnd);
+    socket.on('error', socketOnError);
+
+    this.readyState = WebSocket.OPEN;
+    this.emit('open');
+  }
+
+  /**
+   * Emit the `'close'` event.
+   *
+   * @private
+   */
+  emitClose() {
+    if (!this._socket) {
+      this.readyState = WebSocket.CLOSED;
+      this.emit('close', this._closeCode, this._closeMessage);
+      return;
+    }
+
+    if (this._extensions[PerMessageDeflate.extensionName]) {
+      this._extensions[PerMessageDeflate.extensionName].cleanup();
+    }
+
+    this._receiver.removeAllListeners();
+    this.readyState = WebSocket.CLOSED;
+    this.emit('close', this._closeCode, this._closeMessage);
+  }
+
+  /**
+   * Start a closing handshake.
+   *
+   *          +----------+   +-----------+   +----------+
+   *     - - -|ws.close()|-->|close frame|-->|ws.close()|- - -
+   *    |     +----------+   +-----------+   +----------+     |
+   *          +----------+   +-----------+         |
+   * CLOSING  |ws.close()|<--|close frame|<--+-----+       CLOSING
+   *          +----------+   +-----------+   |
+   *    |           |                        |   +---+        |
+   *                +------------------------+-->|fin| - - - -
+   *    |         +---+                      |   +---+
+   *     - - - - -|fin|<---------------------+
+   *              +---+
+   *
+   * @param {Number} code Status code explaining why the connection is closing
+   * @param {String} data A string explaining why the connection is closing
+   * @public
+   */
+  close(code, data) {
+    if (this.readyState === WebSocket.CLOSED) return;
+    if (this.readyState === WebSocket.CONNECTING) {
+      const msg = 'WebSocket was closed before the connection was established';
+      return abortHandshake(this, this._req, msg);
+    }
+
+    if (this.readyState === WebSocket.CLOSING) {
+      if (this._closeFrameSent && this._closeFrameReceived) this._socket.end();
+      return;
+    }
+
+    this.readyState = WebSocket.CLOSING;
+    this._sender.close(code, data, !this._isServer, (err) => {
+      //
+      // This error is handled by the `'error'` listener on the socket. We only
+      // want to know if the close frame has been sent here.
+      //
+      if (err) return;
+
+      this._closeFrameSent = true;
+      if (this._closeFrameReceived) this._socket.end();
+    });
+
+    //
+    // Specify a timeout for the closing handshake to complete.
+    //
+    this._closeTimer = setTimeout(
+      this._socket.destroy.bind(this._socket),
+      closeTimeout
+    );
+  }
+
+  /**
+   * Send a ping.
+   *
+   * @param {*} data The data to send
+   * @param {Boolean} mask Indicates whether or not to mask `data`
+   * @param {Function} cb Callback which is executed when the ping is sent
+   * @public
+   */
+  ping(data, mask, cb) {
+    if (this.readyState === WebSocket.CONNECTING) {
+      throw new Error('WebSocket is not open: readyState 0 (CONNECTING)');
+    }
+
+    if (typeof data === 'function') {
+      cb = data;
+      data = mask = undefined;
+    } else if (typeof mask === 'function') {
+      cb = mask;
+      mask = undefined;
+    }
+
+    if (typeof data === 'number') data = data.toString();
+
+    if (this.readyState !== WebSocket.OPEN) {
+      sendAfterClose(this, data, cb);
+      return;
+    }
+
+    if (mask === undefined) mask = !this._isServer;
+    this._sender.ping(data || EMPTY_BUFFER, mask, cb);
+  }
+
+  /**
+   * Send a pong.
+   *
+   * @param {*} data The data to send
+   * @param {Boolean} mask Indicates whether or not to mask `data`
+   * @param {Function} cb Callback which is executed when the pong is sent
+   * @public
+   */
+  pong(data, mask, cb) {
+    if (this.readyState === WebSocket.CONNECTING) {
+      throw new Error('WebSocket is not open: readyState 0 (CONNECTING)');
+    }
+
+    if (typeof data === 'function') {
+      cb = data;
+      data = mask = undefined;
+    } else if (typeof mask === 'function') {
+      cb = mask;
+      mask = undefined;
+    }
+
+    if (typeof data === 'number') data = data.toString();
+
+    if (this.readyState !== WebSocket.OPEN) {
+      sendAfterClose(this, data, cb);
+      return;
+    }
+
+    if (mask === undefined) mask = !this._isServer;
+    this._sender.pong(data || EMPTY_BUFFER, mask, cb);
+  }
+
+  /**
+   * Send a data message.
+   *
+   * @param {*} data The message to send
+   * @param {Object} options Options object
+   * @param {Boolean} options.compress Specifies whether or not to compress
+   *     `data`
+   * @param {Boolean} options.binary Specifies whether `data` is binary or text
+   * @param {Boolean} options.fin Specifies whether the fragment is the last one
+   * @param {Boolean} options.mask Specifies whether or not to mask `data`
+   * @param {Function} cb Callback which is executed when data is written out
+   * @public
+   */
+  send(data, options, cb) {
+    if (this.readyState === WebSocket.CONNECTING) {
+      throw new Error('WebSocket is not open: readyState 0 (CONNECTING)');
+    }
+
+    if (typeof options === 'function') {
+      cb = options;
+      options = {};
+    }
+
+    if (typeof data === 'number') data = data.toString();
+
+    if (this.readyState !== WebSocket.OPEN) {
+      sendAfterClose(this, data, cb);
+      return;
+    }
+
+    const opts = {
+      binary: typeof data !== 'string',
+      mask: !this._isServer,
+      compress: true,
+      fin: true,
+      ...options
+    };
+
+    if (!this._extensions[PerMessageDeflate.extensionName]) {
+      opts.compress = false;
+    }
+
+    this._sender.send(data || EMPTY_BUFFER, opts, cb);
+  }
+
+  /**
+   * Forcibly close the connection.
+   *
+   * @public
+   */
+  terminate() {
+    if (this.readyState === WebSocket.CLOSED) return;
+    if (this.readyState === WebSocket.CONNECTING) {
+      const msg = 'WebSocket was closed before the connection was established';
+      return abortHandshake(this, this._req, msg);
+    }
+
+    if (this._socket) {
+      this.readyState = WebSocket.CLOSING;
+      this._socket.destroy();
+    }
+  }
+}
+
+readyStates.forEach((readyState, i) => {
+  WebSocket[readyState] = i;
+});
+
+//
+// Add the `onopen`, `onerror`, `onclose`, and `onmessage` attributes.
+// See https://html.spec.whatwg.org/multipage/comms.html#the-websocket-interface
+//
+['open', 'error', 'close', 'message'].forEach((method) => {
+  Object.defineProperty(WebSocket.prototype, `on${method}`, {
+    /**
+     * Return the listener of the event.
+     *
+     * @return {(Function|undefined)} The event listener or `undefined`
+     * @public
+     */
+    get() {
+      const listeners = this.listeners(method);
+      for (let i = 0; i < listeners.length; i++) {
+        if (listeners[i]._listener) return listeners[i]._listener;
+      }
+
+      return undefined;
+    },
+    /**
+     * Add a listener for the event.
+     *
+     * @param {Function} listener The listener to add
+     * @public
+     */
+    set(listener) {
+      const listeners = this.listeners(method);
+      for (let i = 0; i < listeners.length; i++) {
+        //
+        // Remove only the listeners added via `addEventListener`.
+        //
+        if (listeners[i]._listener) this.removeListener(method, listeners[i]);
+      }
+      this.addEventListener(method, listener);
+    }
+  });
+});
+
+WebSocket.prototype.addEventListener = addEventListener;
+WebSocket.prototype.removeEventListener = removeEventListener;
+
+module.exports = WebSocket;
+
+/**
+ * Initialize a WebSocket client.
+ *
+ * @param {WebSocket} websocket The client to initialize
+ * @param {(String|url.URL)} address The URL to which to connect
+ * @param {String} protocols The subprotocols
+ * @param {Object} options Connection options
+ * @param {(Boolean|Object)} options.perMessageDeflate Enable/disable
+ *     permessage-deflate
+ * @param {Number} options.handshakeTimeout Timeout in milliseconds for the
+ *     handshake request
+ * @param {Number} options.protocolVersion Value of the `Sec-WebSocket-Version`
+ *     header
+ * @param {String} options.origin Value of the `Origin` or
+ *     `Sec-WebSocket-Origin` header
+ * @param {Number} options.maxPayload The maximum allowed message size
+ * @param {Boolean} options.followRedirects Whether or not to follow redirects
+ * @param {Number} options.maxRedirects The maximum number of redirects allowed
+ * @private
+ */
+function initAsClient(websocket, address, protocols, options) {
+  const opts = {
+    protocolVersion: protocolVersions[1],
+    maxPayload: 100 * 1024 * 1024,
+    perMessageDeflate: true,
+    followRedirects: false,
+    maxRedirects: 10,
+    ...options,
+    createConnection: undefined,
+    socketPath: undefined,
+    hostname: undefined,
+    protocol: undefined,
+    timeout: undefined,
+    method: undefined,
+    auth: undefined,
+    host: undefined,
+    path: undefined,
+    port: undefined
+  };
+
+  if (!protocolVersions.includes(opts.protocolVersion)) {
+    throw new RangeError(
+      `Unsupported protocol version: ${opts.protocolVersion} ` +
+        `(supported versions: ${protocolVersions.join(', ')})`
+    );
+  }
+
+  let parsedUrl;
+
+  if (address instanceof URL) {
+    parsedUrl = address;
+    websocket.url = address.href;
+  } else {
+    parsedUrl = new URL(address);
+    websocket.url = address;
+  }
+
+  const isUnixSocket = parsedUrl.protocol === 'ws+unix:';
+
+  if (!parsedUrl.host && (!isUnixSocket || !parsedUrl.pathname)) {
+    throw new Error(`Invalid URL: ${websocket.url}`);
+  }
+
+  const isSecure =
+    parsedUrl.protocol === 'wss:' || parsedUrl.protocol === 'https:';
+  const defaultPort = isSecure ? 443 : 80;
+  const key = randomBytes(16).toString('base64');
+  const get = isSecure ? https.get : http.get;
+  let perMessageDeflate;
+
+  opts.createConnection = isSecure ? tlsConnect : netConnect;
+  opts.defaultPort = opts.defaultPort || defaultPort;
+  opts.port = parsedUrl.port || defaultPort;
+  opts.host = parsedUrl.hostname.startsWith('[')
+    ? parsedUrl.hostname.slice(1, -1)
+    : parsedUrl.hostname;
+  opts.headers = {
+    'Sec-WebSocket-Version': opts.protocolVersion,
+    'Sec-WebSocket-Key': key,
+    Connection: 'Upgrade',
+    Upgrade: 'websocket',
+    ...opts.headers
+  };
+  opts.path = parsedUrl.pathname + parsedUrl.search;
+  opts.timeout = opts.handshakeTimeout;
+
+  if (opts.perMessageDeflate) {
+    perMessageDeflate = new PerMessageDeflate(
+      opts.perMessageDeflate !== true ? opts.perMessageDeflate : {},
+      false,
+      opts.maxPayload
+    );
+    opts.headers['Sec-WebSocket-Extensions'] = format({
+      [PerMessageDeflate.extensionName]: perMessageDeflate.offer()
+    });
+  }
+  if (protocols) {
+    opts.headers['Sec-WebSocket-Protocol'] = protocols;
+  }
+  if (opts.origin) {
+    if (opts.protocolVersion < 13) {
+      opts.headers['Sec-WebSocket-Origin'] = opts.origin;
+    } else {
+      opts.headers.Origin = opts.origin;
+    }
+  }
+  if (parsedUrl.username || parsedUrl.password) {
+    opts.auth = `${parsedUrl.username}:${parsedUrl.password}`;
+  }
+
+  if (isUnixSocket) {
+    const parts = opts.path.split(':');
+
+    opts.socketPath = parts[0];
+    opts.path = parts[1];
+  }
+
+  let req = (websocket._req = get(opts));
+
+  if (opts.timeout) {
+    req.on('timeout', () => {
+      abortHandshake(websocket, req, 'Opening handshake has timed out');
+    });
+  }
+
+  req.on('error', (err) => {
+    if (websocket._req.aborted) return;
+
+    req = websocket._req = null;
+    websocket.readyState = WebSocket.CLOSING;
+    websocket.emit('error', err);
+    websocket.emitClose();
+  });
+
+  req.on('response', (res) => {
+    const location = res.headers.location;
+    const statusCode = res.statusCode;
+
+    if (
+      location &&
+      opts.followRedirects &&
+      statusCode >= 300 &&
+      statusCode < 400
+    ) {
+      if (++websocket._redirects > opts.maxRedirects) {
+        abortHandshake(websocket, req, 'Maximum redirects exceeded');
+        return;
+      }
+
+      req.abort();
+
+      const addr = new URL(location, address);
+
+      initAsClient(websocket, addr, protocols, options);
+    } else if (!websocket.emit('unexpected-response', req, res)) {
+      abortHandshake(
+        websocket,
+        req,
+        `Unexpected server response: ${res.statusCode}`
+      );
+    }
+  });
+
+  req.on('upgrade', (res, socket, head) => {
+    websocket.emit('upgrade', res);
+
+    //
+    // The user may have closed the connection from a listener of the `upgrade`
+    // event.
+    //
+    if (websocket.readyState !== WebSocket.CONNECTING) return;
+
+    req = websocket._req = null;
+
+    const digest = createHash('sha1')
+      .update(key + GUID)
+      .digest('base64');
+
+    if (res.headers['sec-websocket-accept'] !== digest) {
+      abortHandshake(websocket, socket, 'Invalid Sec-WebSocket-Accept header');
+      return;
+    }
+
+    const serverProt = res.headers['sec-websocket-protocol'];
+    const protList = (protocols || '').split(/, */);
+    let protError;
+
+    if (!protocols && serverProt) {
+      protError = 'Server sent a subprotocol but none was requested';
+    } else if (protocols && !serverProt) {
+      protError = 'Server sent no subprotocol';
+    } else if (serverProt && !protList.includes(serverProt)) {
+      protError = 'Server sent an invalid subprotocol';
+    }
+
+    if (protError) {
+      abortHandshake(websocket, socket, protError);
+      return;
+    }
+
+    if (serverProt) websocket.protocol = serverProt;
+
+    if (perMessageDeflate) {
+      try {
+        const extensions = parse(res.headers['sec-websocket-extensions']);
+
+        if (extensions[PerMessageDeflate.extensionName]) {
+          perMessageDeflate.accept(extensions[PerMessageDeflate.extensionName]);
+          websocket._extensions[
+            PerMessageDeflate.extensionName
+          ] = perMessageDeflate;
+        }
+      } catch (err) {
+        abortHandshake(
+          websocket,
+          socket,
+          'Invalid Sec-WebSocket-Extensions header'
+        );
+        return;
+      }
+    }
+
+    websocket.setSocket(socket, head, opts.maxPayload);
+  });
+}
+
+/**
+ * Create a `net.Socket` and initiate a connection.
+ *
+ * @param {Object} options Connection options
+ * @return {net.Socket} The newly created socket used to start the connection
+ * @private
+ */
+function netConnect(options) {
+  options.path = options.socketPath;
+  return net.connect(options);
+}
+
+/**
+ * Create a `tls.TLSSocket` and initiate a connection.
+ *
+ * @param {Object} options Connection options
+ * @return {tls.TLSSocket} The newly created socket used to start the connection
+ * @private
+ */
+function tlsConnect(options) {
+  options.path = undefined;
+
+  if (!options.servername && options.servername !== '') {
+    options.servername = options.host;
+  }
+
+  return tls.connect(options);
+}
+
+/**
+ * Abort the handshake and emit an error.
+ *
+ * @param {WebSocket} websocket The WebSocket instance
+ * @param {(http.ClientRequest|net.Socket)} stream The request to abort or the
+ *     socket to destroy
+ * @param {String} message The error message
+ * @private
+ */
+function abortHandshake(websocket, stream, message) {
+  websocket.readyState = WebSocket.CLOSING;
+
+  const err = new Error(message);
+  Error.captureStackTrace(err, abortHandshake);
+
+  if (stream.setHeader) {
+    stream.abort();
+    stream.once('abort', websocket.emitClose.bind(websocket));
+    websocket.emit('error', err);
+  } else {
+    stream.destroy(err);
+    stream.once('error', websocket.emit.bind(websocket, 'error'));
+    stream.once('close', websocket.emitClose.bind(websocket));
+  }
+}
+
+/**
+ * Handle cases where the `ping()`, `pong()`, or `send()` methods are called
+ * when the `readyState` attribute is `CLOSING` or `CLOSED`.
+ *
+ * @param {WebSocket} websocket The WebSocket instance
+ * @param {*} data The data to send
+ * @param {Function} cb Callback
+ * @private
+ */
+function sendAfterClose(websocket, data, cb) {
+  if (data) {
+    const length = toBuffer(data).length;
+
+    //
+    // The `_bufferedAmount` property is used only when the peer is a client and
+    // the opening handshake fails. Under these circumstances, in fact, the
+    // `setSocket()` method is not called, so the `_socket` and `_sender`
+    // properties are set to `null`.
+    //
+    if (websocket._socket) websocket._sender._bufferedBytes += length;
+    else websocket._bufferedAmount += length;
+  }
+
+  if (cb) {
+    const err = new Error(
+      `WebSocket is not open: readyState ${websocket.readyState} ` +
+        `(${readyStates[websocket.readyState]})`
+    );
+    cb(err);
+  }
+}
+
+/**
+ * The listener of the `Receiver` `'conclude'` event.
+ *
+ * @param {Number} code The status code
+ * @param {String} reason The reason for closing
+ * @private
+ */
+function receiverOnConclude(code, reason) {
+  const websocket = this[kWebSocket];
+
+  websocket._socket.removeListener('data', socketOnData);
+  websocket._socket.resume();
+
+  websocket._closeFrameReceived = true;
+  websocket._closeMessage = reason;
+  websocket._closeCode = code;
+
+  if (code === 1005) websocket.close();
+  else websocket.close(code, reason);
+}
+
+/**
+ * The listener of the `Receiver` `'drain'` event.
+ *
+ * @private
+ */
+function receiverOnDrain() {
+  this[kWebSocket]._socket.resume();
+}
+
+/**
+ * The listener of the `Receiver` `'error'` event.
+ *
+ * @param {(RangeError|Error)} err The emitted error
+ * @private
+ */
+function receiverOnError(err) {
+  const websocket = this[kWebSocket];
+
+  websocket._socket.removeListener('data', socketOnData);
+
+  websocket.readyState = WebSocket.CLOSING;
+  websocket._closeCode = err[kStatusCode];
+  websocket.emit('error', err);
+  websocket._socket.destroy();
+}
+
+/**
+ * The listener of the `Receiver` `'finish'` event.
+ *
+ * @private
+ */
+function receiverOnFinish() {
+  this[kWebSocket].emitClose();
+}
+
+/**
+ * The listener of the `Receiver` `'message'` event.
+ *
+ * @param {(String|Buffer|ArrayBuffer|Buffer[])} data The message
+ * @private
+ */
+function receiverOnMessage(data) {
+  this[kWebSocket].emit('message', data);
+}
+
+/**
+ * The listener of the `Receiver` `'ping'` event.
+ *
+ * @param {Buffer} data The data included in the ping frame
+ * @private
+ */
+function receiverOnPing(data) {
+  const websocket = this[kWebSocket];
+
+  websocket.pong(data, !websocket._isServer, NOOP);
+  websocket.emit('ping', data);
+}
+
+/**
+ * The listener of the `Receiver` `'pong'` event.
+ *
+ * @param {Buffer} data The data included in the pong frame
+ * @private
+ */
+function receiverOnPong(data) {
+  this[kWebSocket].emit('pong', data);
+}
+
+/**
+ * The listener of the `net.Socket` `'close'` event.
+ *
+ * @private
+ */
+function socketOnClose() {
+  const websocket = this[kWebSocket];
+
+  this.removeListener('close', socketOnClose);
+  this.removeListener('end', socketOnEnd);
+
+  websocket.readyState = WebSocket.CLOSING;
+
+  //
+  // The close frame might not have been received or the `'end'` event emitted,
+  // for example, if the socket was destroyed due to an error. Ensure that the
+  // `receiver` stream is closed after writing any remaining buffered data to
+  // it. If the readable side of the socket is in flowing mode then there is no
+  // buffered data as everything has been already written and `readable.read()`
+  // will return `null`. If instead, the socket is paused, any possible buffered
+  // data will be read as a single chunk and emitted synchronously in a single
+  // `'data'` event.
+  //
+  websocket._socket.read();
+  websocket._receiver.end();
+
+  this.removeListener('data', socketOnData);
+  this[kWebSocket] = undefined;
+
+  clearTimeout(websocket._closeTimer);
+
+  if (
+    websocket._receiver._writableState.finished ||
+    websocket._receiver._writableState.errorEmitted
+  ) {
+    websocket.emitClose();
+  } else {
+    websocket._receiver.on('error', receiverOnFinish);
+    websocket._receiver.on('finish', receiverOnFinish);
+  }
+}
+
+/**
+ * The listener of the `net.Socket` `'data'` event.
+ *
+ * @param {Buffer} chunk A chunk of data
+ * @private
+ */
+function socketOnData(chunk) {
+  if (!this[kWebSocket]._receiver.write(chunk)) {
+    this.pause();
+  }
+}
+
+/**
+ * The listener of the `net.Socket` `'end'` event.
+ *
+ * @private
+ */
+function socketOnEnd() {
+  const websocket = this[kWebSocket];
+
+  websocket.readyState = WebSocket.CLOSING;
+  websocket._receiver.end();
+  this.end();
+}
+
+/**
+ * The listener of the `net.Socket` `'error'` event.
+ *
+ * @private
+ */
+function socketOnError() {
+  const websocket = this[kWebSocket];
+
+  this.removeListener('error', socketOnError);
+  this.on('error', NOOP);
+
+  if (websocket) {
+    websocket.readyState = WebSocket.CLOSING;
+    this.destroy();
+  }
+}
@@ -0,0 +1,97 @@
+{
+  "_from": "ws@^7.1.2",
+  "_id": "ws@7.2.3",
+  "_inBundle": false,
+  "_integrity": "sha512-HTDl9G9hbkNDk98naoR/cHDws7+EyYMOdL1BmjsZXRUjf7d+MficC4B7HLUPlSiho0vg+CWKrGIt/VJBd1xunQ==",
+  "_location": "/ws",
+  "_phantomChildren": {},
+  "_requested": {
+    "type": "range",
+    "registry": true,
+    "raw": "ws@^7.1.2",
+    "name": "ws",
+    "escapedName": "ws",
+    "rawSpec": "^7.1.2",
+    "saveSpec": null,
+    "fetchSpec": "^7.1.2"
+  },
+  "_requiredBy": [
+    "/"
+  ],
+  "_resolved": "https://registry.npmjs.org/ws/-/ws-7.2.3.tgz",
+  "_shasum": "a5411e1fb04d5ed0efee76d26d5c46d830c39b46",
+  "_spec": "ws@^7.1.2",
+  "_where": "C:\\Users\\Luis\\source\\repos\\AAMasters\\BackendServers",
+  "author": {
+    "name": "Einar Otto Stangvik",
+    "email": "einaros@gmail.com",
+    "url": "http://2x.io"
+  },
+  "browser": "browser.js",
+  "bugs": {
+    "url": "https://github.com/websockets/ws/issues"
+  },
+  "bundleDependencies": false,
+  "deprecated": false,
+  "description": "Simple to use, blazing fast and thoroughly tested websocket client and server for Node.js",
+  "devDependencies": {
+    "benchmark": "^2.1.4",
+    "bufferutil": "^4.0.1",
+    "coveralls": "^3.0.3",
+    "eslint": "^6.0.0",
+    "eslint-config-prettier": "^6.0.0",
+    "eslint-plugin-prettier": "^3.0.1",
+    "mocha": "^7.0.0",
+    "nyc": "^15.0.0",
+    "prettier": "^1.17.0",
+    "utf-8-validate": "^5.0.2"
+  },
+  "engines": {
+    "node": ">=8.3.0"
+  },
+  "files": [
+    "browser.js",
+    "index.js",
+    "lib/*.js"
+  ],
+  "greenkeeper": {
+    "commitMessages": {
+      "dependencyUpdate": "[pkg] Update ${dependency} to version ${version}",
+      "devDependencyUpdate": "[pkg] Update ${dependency} to version ${version}"
+    }
+  },
+  "homepage": "https://github.com/websockets/ws",
+  "keywords": [
+    "HyBi",
+    "Push",
+    "RFC-6455",
+    "WebSocket",
+    "WebSockets",
+    "real-time"
+  ],
+  "license": "MIT",
+  "main": "index.js",
+  "name": "ws",
+  "peerDependencies": {
+    "bufferutil": "^4.0.1",
+    "utf-8-validate": "^5.0.2"
+  },
+  "peerDependenciesMeta": {
+    "bufferutil": {
+      "optional": true
+    },
+    "utf-8-validate": {
+      "optional": true
+    }
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/websockets/ws.git"
+  },
+  "scripts": {
+    "integration": "npm run lint && mocha --throw-deprecation test/*.integration.js",
+    "lint": "eslint --ignore-path .gitignore . && prettier --check --ignore-path .gitignore \"**/*.{json,md,yaml,yml}\"",
+    "test": "npm run lint && nyc --reporter=html --reporter=text mocha --throw-deprecation test/*.test.js"
+  },
+  "version": "7.2.3"
+}
@@ -0,0 +1,23 @@
+{
+  "name": "backend-server",
+  "version": "0.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "child_process": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/child_process/-/child_process-1.0.2.tgz",
+      "integrity": "sha1-sffn/HPSXn/R1FWtyU4UODAYK1o="
+    },
+    "dotenv": {
+      "version": "8.2.0",
+      "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-8.2.0.tgz",
+      "integrity": "sha512-8sJ78ElpbDJBHNeBzUbUVLsqKdccaa/BXF1uPTw3GrvQTBgrQrtObr2mUrE38vzYd8cEv+m/JBfDLioYcfXoaw=="
+    },
+    "ws": {
+      "version": "7.2.3",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-7.2.3.tgz",
+      "integrity": "sha512-HTDl9G9hbkNDk98naoR/cHDws7+EyYMOdL1BmjsZXRUjf7d+MficC4B7HLUPlSiho0vg+CWKrGIt/VJBd1xunQ=="
+    }
+  }
+}
@@ -0,0 +1,14 @@
+{
+  "name": "backend-server",
+  "version": "0.0.0",
+  "description": "BackendServer",
+  "main": "app.js",
+  "author": {
+    "name": "Luis"
+  },
+  "dependencies": {
+    "child_process": "^1.0.2",
+    "dotenv": "^8.2.0",
+    "ws": "^7.1.2"
+  }
+}
@@ -0,0 +1,49 @@
+
+process.on('uncaughtException', function (err) {
+    if (err.message.indexOf("EADDRINUSE") > 0) {
+        console.log("Superalgos Backend Server cannot be started. Reason: the port " + port + " is already in use by another application.")
+        return
+    }
+    console.log('[ERROR] Backend Server -> server -> uncaughtException -> err.message = ' + err.message)
+    console.log('[ERROR] Backend Server -> server -> uncaughtException -> err.stack = ' + err.stack)
+    process.exit(1)
+})
+
+process.on('unhandledRejection', (reason, p) => {
+    console.log('[ERROR] Backend Server -> server -> unhandledRejection -> reason = ' + JSON.stringify(reason))
+    console.log('[ERROR] Backend Server -> server -> unhandledRejection -> p = ' + JSON.stringify(p))
+    process.exit(1)
+})
+
+/* Callbacks default responses. */
+
+global.DEFAULT_OK_RESPONSE = {
+    result: "Ok",
+    message: "Operation Succeeded"
+};
+
+global.DEFAULT_FAIL_RESPONSE = {
+    result: "Fail",
+    message: "Operation Failed"
+};
+
+let EVENTS_SERVER = require('./eventsServer.js');
+let WEB_SOCKETS_SERVER = require('./webSocketsServer.js');
+let TASK_MANAGER_SERVER = require('./taskManagerServer.js');
+
+try {
+    EVENTS_SERVER = EVENTS_SERVER.newEventsServer()
+    EVENTS_SERVER.initialize()
+    EVENTS_SERVER.run()
+
+    WEB_SOCKETS_SERVER = WEB_SOCKETS_SERVER.newWebSocketsServer(EVENTS_SERVER)
+    WEB_SOCKETS_SERVER.initialize()
+    WEB_SOCKETS_SERVER.run()
+
+    TASK_MANAGER_SERVER = TASK_MANAGER_SERVER.newTaskManagerServer(WEB_SOCKETS_SERVER, EVENTS_SERVER)
+    TASK_MANAGER_SERVER.initialize()
+    TASK_MANAGER_SERVER.run()
+} catch (err) {
+    console.log('[ERROR] BackendServers -> Task Manager -> server -> Error = ' + err.stack)
+}
+
@@ -0,0 +1,295 @@
+exports.newTaskManagerServer = function newTaskManagerServer(WEB_SOCKETS_SERVER, EVENTS_SERVER) {
+
+    const MODULE = "Task Manager Server"
+
+    let thisObject = {
+        initialize: initialize,
+        finalize: finalize,
+        run: run
+    }
+
+    /*
+
+    This server creates and destroys Task Servers according to what is going on at the UI. Each of these created servers will do their own
+    work. The responsibility of this server is to manage those children processes in order to be in sync with what the end user want and is defining
+    at the user interface.
+
+    */
+
+    const { fork } = require('child_process')
+    require('dotenv').config()
+    tasks = new Map()
+
+    return thisObject
+
+    function finalize() {
+
+    }
+
+    function initialize() {
+
+    }
+
+    function run() {
+
+        /*
+        
+        Here we will create an Event Handler for this server. After that we will listen to events happening here. Elements of the UI will raise events here,
+        as a way to communicate what is going on with the user interacting with UI components. That is the way this server will know for example when a new
+        task needs to be created or destroyed.
+        
+        */
+
+        let eventsServerClient = newEventsServerClient()
+        eventsServerClient.createEventHandler('Task Manager')
+        eventsServerClient.listenToEvent('Task Manager', 'Run Task', undefined, undefined, undefined, runTask)
+        eventsServerClient.listenToEvent('Task Manager', 'Stop Task', undefined, undefined, undefined, stopTask)
+
+        console.log('Task Manager Server Started.')
+      
+        function runTask(message) {
+            //console.log('[INFO] BackendServers -> Task Manager Server -> runTask -> Entering function.') 
+
+            if (message.event === undefined) {
+                console.log('[WARN] BackendServers -> Task Manager Server -> runTask -> Message Received Without Event -> message = ' + JSON.stringify(message))
+                return
+            }
+
+            if (message.event.taskId === undefined) {
+                console.log('[WARN] BackendServers -> Task Manager Server -> runTask -> Message Received Without taskId -> message = ' + JSON.stringify(message))
+                return
+            }
+
+            if (message.event.definition === undefined) {
+                console.log('[WARN] BackendServers -> Task Manager Server -> runTask -> Message Received Without Definition -> message = ' + JSON.stringify(message))
+                return
+            }
+
+            if (tasks.get(message.event.taskId) !== undefined) {
+                //console.log('[WARN] BackendServers -> Task Manager Server -> runTask -> Task Already Running -> taskId = ' + message.event.taskId)
+                return
+            }
+            //console.log('[INFO] BackendServers -> Task Manager Server -> runTask -> Task Name = ' + message.event.taskName)
+            //console.log('[INFO] BackendServers -> Task Manager Server -> runTask -> Task Id = ' + message.event.taskId) 
+
+            let path = process.env.TASK_SERVER_PATH + '/server.js'
+
+            /* Workarround to avoid having the same debug port at the forked process which makes it crash. */
+            for (let i = 0; i < process.execArgv.length; i++) {
+                let argument = process.execArgv[i]
+                if (argument.indexOf('--inspect') > -1) {
+                    process.execArgv[i] = ''
+                }
+            }
+
+            /* Forking this process. */
+            let task = {
+                childProcess: fork(path, [message.event.taskId], { stdio: 'inherit' }),
+                id: message.event.taskId,
+                name: message.event.taskName
+            }
+
+            tasks.set(message.event.taskId, task)
+
+            task.childProcess.on('error', (err) => {
+                console.log('[ERROR] BackendServers -> Task Manager Server -> runTask -> Problem with Task Name = ' + task.name)
+                console.log('[ERROR] BackendServers -> Task Manager Server -> runTask -> Problem with Task Id = ' + task.id)
+                console.log(`[ERROR] BackendServers -> Task Manager Server -> runTask -> Task Manager exited with error ${err}`)
+            })
+            task.childProcess.on('close', (code, signal) => {
+                //console.log('[INFO] BackendServers -> Task Manager Server -> runTask -> Task Terminated. -> Task Name = ' + task.name)
+                //console.log('[INFO] BackendServers -> Task Manager Server -> runTask -> Task Terminated. -> Task Id = ' + task.id)
+                tasks.delete(task.id)
+            })
+
+            eventsServerClient.listenToEvent('Task Manager - ' + message.event.taskId, 'Nodejs Process Ready for Task', undefined, undefined, undefined, sendStartingEvent)
+
+            function sendStartingEvent() {
+                //console.log('[INFO] BackendServers -> Task Manager Server -> runTask -> Emitting Event -> key = ' + 'Task Server - ' + task.id)
+                eventsServerClient.raiseEvent('Task Server - ' + task.id, 'Run Task', message.event)
+            }
+        }
+
+        function stopTask(message) {
+
+            //console.log('[INFO] BackendServers -> Task Manager Server -> stopTask -> Entering function.')
+
+            if (message.event === undefined) {
+                console.log('[WARN] BackendServers -> Task Manager Server -> stopTask -> Message Received Without Event -> message = ' + JSON.stringify(message))
+                return
+            }
+
+            if (message.event.taskId === undefined) {
+                console.log('[WARN] BackendServers -> Task Manager Server -> stopTask -> Message Received Without taskId -> message = ' + JSON.stringify(message))
+                return
+            }
+
+            //console.log('[INFO] BackendServers -> Task Manager Server -> stopTask -> Task Name = ' + message.event.taskName)
+            //console.log('[INFO] BackendServers -> Task Manager Server -> stopTask -> Task Id = ' + message.event.taskId) 
+
+            let task = tasks.get(message.event.taskId)
+
+            if (task) {
+                task.childProcess.send('Stop this Task');
+                //console.log('[INFO] BackendServers -> Task Manager Server -> stopTask -> Child Process instructed to finish.')
+            } else {
+                console.log('[WARN] BackendServers -> Task Manager Server -> stopTask -> Cannot delete Task that does not exist.')
+            }
+        }
+    }
+
+    function newEventsServerClient() {
+        let thisObject = {
+            initialize: initialize,
+            finalize: finalize,
+            createEventHandler: createEventHandler,
+            deleteEventHandler: deleteEventHandler,
+            listenToEvent: listenToEvent,
+            stopListening: stopListening,
+            raiseEvent: raiseEvent,
+            onMessage: onMessage
+        }
+
+        let eventListeners = new Map()
+        let responseWaiters = new Map()
+
+        return thisObject
+
+
+        function finalize() {
+            /* Before disconnecting we will forze all eventListeners to stop listening. */
+            const eventListenersArray = [...eventListeners.values()]
+            for (let i = 0; i < eventListenersArray.length; i++) {
+                let handler = eventListenersArray[i]
+                let eventCommand = {
+                    action: 'stopListening',
+                    eventHandlerName: handler.eventHandlerName,
+                    eventType: handler.eventType,
+                    callerId: handler.callerId
+                }
+                sendCommand(eventCommand)
+            }
+        }
+
+        function initialize() {
+
+        }
+
+        function onMessage(data) {
+            try {
+                let message = JSON.parse(data)
+
+                if (message.action === 'Event Raised') {
+                    let key
+                    if (message.callerId) {
+                        key = message.eventHandlerName + '-' + message.eventType + '-' + message.callerId
+                    } else {
+                        key = message.eventHandlerName + '-' + message.eventType
+                    }
+                    let handler = eventListeners.get(key)
+                    if (handler) {
+                        handler.callBack(message)
+                    } else {
+                        console.log(key + ' not found so could not deliver event raised.')
+                        console.log(' Message = ' + data)
+                    }
+                    return
+                }
+
+                if (message.action === 'Event Server Response') {
+                    let handler = responseWaiters.get(message.callerId)
+                    if (handler) {
+                        handler(message)
+                    }
+                    return
+                }
+            } catch (err) {
+                console.log('[ERROR] BackendServers -> Task Manager Server -> onMessage -> Error Receiving Message from Events Server -> data = ' + JSON.stringify(data))
+                console.log('[ERROR] BackendServers -> Task Manager Server -> onMessage -> Error Receiving Message from Events Server -> error = ' + err.stack)
+            }
+        }
+
+        function sendCommand(command, responseCallBack, eventsCallBack) {
+            try {
+                if (command.action === 'listenToEvent') {
+                    let key
+                    if (command.callerId) {
+                        key = command.eventHandlerName + '-' + command.eventType + '-' + command.callerId
+                    } else {
+                        key = command.eventHandlerName + '-' + command.eventType
+                    }
+                    let handler = {
+                        eventHandlerName: command.eventHandlerName,
+                        eventType: command.eventType,
+                        callerId: command.callerId,
+                        callBack: eventsCallBack
+                    }
+                    eventListeners.set(key, handler)
+                }
+                if (command.callerId && responseCallBack) {
+                    responseWaiters.set(command.callerId, responseCallBack)
+                }
+
+                EVENTS_SERVER.onMessage(JSON.stringify(command), thisObject.onMessage)
+            } catch (err) {
+                console.log('[ERROR] BackendServers -> Task Manager Server -> sendCommand -> Error Sending Command to Events Server -> command = ' + JSON.stringify(command))
+                console.log('[ERROR] BackendServers -> Task Manager Server -> sendCommand -> Error Sending Command to Events Server -> error = ' + err.stack)
+            }
+        }
+
+        function createEventHandler(eventHandlerName, callerId, responseCallBack) {
+            let eventCommand = {
+                action: 'createEventHandler',
+                eventHandlerName: eventHandlerName,
+                callerId: callerId
+            }
+            sendCommand(eventCommand, responseCallBack)
+        }
+
+        function deleteEventHandler(eventHandlerName, callerId, responseCallBack) {
+            let eventCommand = {
+                action: 'deleteEventHandler',
+                eventHandlerName: eventHandlerName,
+                callerId: callerId
+            }
+            sendCommand(eventCommand, responseCallBack)
+        }
+
+        function listenToEvent(eventHandlerName, eventType, extraData, callerId, responseCallBack, eventsCallBack) {
+            let eventCommand = {
+                action: 'listenToEvent',
+                eventHandlerName: eventHandlerName,
+                eventType: eventType,
+                extraData: extraData,
+                callerId: callerId
+            }
+            sendCommand(eventCommand, responseCallBack, eventsCallBack)
+        }
+
+        function stopListening(eventHandlerName, eventType, eventSubscriptionId, callerId, responseCallBack) {
+            /* User either needs to specify a valid eventSubscriptionId OR the 3 params: eventHandlerName, eventType, callerId which were used when start listening to events. */
+            let eventCommand = {
+                action: 'stopListening',
+                eventHandlerName: eventHandlerName,
+                eventType: eventType,
+                eventSubscriptionId: eventSubscriptionId,
+                callerId: callerId
+            }
+            sendCommand(eventCommand, responseCallBack)
+        }
+
+        function raiseEvent(eventHandlerName, eventType, event, callerId, responseCallBack) {
+            let eventCommand = {
+                action: 'raiseEvent',
+                eventHandlerName: eventHandlerName,
+                eventType: eventType,
+                event: event,
+                callerId: callerId
+            }
+            sendCommand(eventCommand, responseCallBack)
+        }
+    }
+}
+
+
+
@@ -0,0 +1,112 @@
+exports.newWebSocketsServer = function newWebSocketsServer(EVENTS_SERVER) {
+
+    const MODULE = "Web Sockets Server"
+    const LOG_INFO = false
+
+    let thisObject = {
+        initialize: initialize,
+        finalize: finalize,
+        run: run
+    }
+
+    require('dotenv').config()
+    const WEB_SOCKET = require('ws')
+    let socketServer
+    let port = process.env.WEB_SOCKETS_SERVER_PORT  
+
+    return thisObject
+
+    function finalize() {
+
+    }
+
+    function initialize() {
+
+    }
+
+    function run() {
+       setUpWebSocketServer()
+    }
+
+    function setUpWebSocketServer() {
+        try {
+            socketServer = new WEB_SOCKET.Server({ port: port })
+
+            socketServer.on('connection', onConnection)
+
+            function onConnection(socket) {
+
+                let lastNonce = -1
+                if (LOG_INFO === true) {
+                    console.log('New Websocket Connection.')
+                }
+
+                socket.on('message', onMenssage)
+
+                function onMenssage(message){
+
+                    try {
+                        if (LOG_INFO === true) {
+                            console.log('Message Received: ' + message)
+                        }
+
+                        let messageArray = message.split('|')
+
+                        let origin = messageArray[0]
+                        let nonce = messageArray[1]
+                        let messageToEventServer = messageArray[2]
+
+                        if (origin === 'Web Browser') {
+                            if (isNaN(nonce) || nonce === "") {
+                                console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Nonce is not a Number. message = ' + message)
+                                console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Nonce is not a Number. nonce = ' + nonce)
+                                return
+                            }
+
+                            if (nonce === "1") { // this happens once the browser is restarted, and the server is running since a previous session.
+                                lastNonce = 0
+                            }
+
+                            if (Number(nonce) < Number(lastNonce)) {
+                                console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Nonce received is less than Last Nonce. message = ' + message)
+                                console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Nonce received is less than Last Nonce. nonce = ' + nonce)
+                                console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Nonce received is less than Last Nonce. lastNonce = ' + lastNonce)
+                                return
+                            }
+
+                            lastNonce = nonce
+
+                            try {
+                                let jsonCheck = JSON.parse(messageToEventServer)
+                            } catch (err) {
+                                console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Message received from the browser is not a valid JSON. message = ' + message)
+                                console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Message received from the browser is not a valid JSON. messageToEventServer = ' + messageToEventServer)
+                                return
+                            }
+
+                            let acknowledgeMessage = {
+                                action: 'Acknowledge',
+                                nonce: nonce
+                            }
+
+                            socket.send(JSON.stringify(acknowledgeMessage))
+                        }
+
+
+                        EVENTS_SERVER.onMessage(messageToEventServer, onResponse)
+
+                        function onResponse(message) {
+                            socket.send(message)
+                        }
+                    } catch (err) {
+                        console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> Nonce received is less than Last Nonce. err = ' + err.stack)
+                    }
+                }
+            }
+
+            console.log('Web Sockets Server Started.')
+        } catch (err) {
+            console.log('[ERROR] BackendServers -> Web Sockets Server -> run -> setUpWebSocketServer -> err.message = ' + err.message)
+        }
+    }
+}