The realtime engine behind Socket.IO. Provides the foundation of a bidirectional connection between client and server. 

The realtime engine behind Socket.IO. Provides the foundation of a bidirectional connection between client and server

rauchg

darrachequesne

engine.io

import { Server, AttachOptions, ServerOptions } from "./server";

import transports from "./transports/index";

import * as parser from "engine.io-parser";

export { Server, transports, listen, attach, parser };

export { AttachOptions, ServerOptions } from "./server";

export type { AttachOptions, ServerOptions, BaseServer } from "./server";

 * Creates an http.Server exclusively used for WS upgrades.

declare function listen(port: any, options: AttachOptions & ServerOptions, fn: any): Server;

 * Captures upgrade requests for a http.Server.

declare function attach(server: any, options: AttachOptions & ServerOptions): Server;

  "description": "The realtime engine behind Socket.IO. Provides the foundation of a bidirectional connection between client and server",

  "author": "Guillermo Rauch <guillermo@learnboost.com>",

  "homepage": "https://github.com/socketio/engine.io",

      "web": "https://github.com/EugenDueck"

      "web": "https://github.com/afshinm"

    "engine.io-client-v3": "npm:engine.io-client@3.5.2",

    "uWebSockets.js": "github:uNetworking/uWebSockets.js#v20.15.0"

    "test": "npm run compile && npm run format:check && npm run test:default && npm run test:compat-v3",

    "test:default": "mocha --bail --exit",

    "test:compat-v3": "EIO_CLIENT=3 mocha --exit",

    "test:eiows": "EIO_WS_ENGINE=eiows mocha --exit",

    "test:uws": "EIO_WS_ENGINE=uws mocha --exit",

    "format:check": "prettier --check \"wrapper.mjs\" \"lib/**/*.ts\" \"test/**/*.js\"",

    "format:fix": "prettier --write \"wrapper.mjs\" \"lib/**/*.ts\" \"test/**/*.js\"",

    "url": "git@github.com:socketio/engine.io.git"

[![Build Status](https://github.com/socketio/engine.io/workflows/CI/badge.svg?branch=master)](https://github.com/socketio/engine.io/actions)

[![NPM version](https://badge.fury.io/js/engine.io.svg)](http://badge.fury.io/js/engine.io)

`Engine.IO` is the implementation of transport-based

cross-browser/cross-device bi-directional communication layer for

[Socket.IO](http://github.com/socketio/socket.io).

  socket.send(Buffer.from([0, 1, 2, 3, 4, 5])); // binary data

#### (B) Intercepting requests for a http.Server

const http = require('http').createServer().listen(3000);

httpServer.on('upgrade', (req, socket, head) => {

  server.handleUpgrade(req, socket, head);

  const socket = new eio.Socket('ws://localhost/');

For more information on the client refer to the

[engine-client](http://github.com/socketio/engine.io-client) repository.

- **Maximum reliability**. Connections are established even in the presence of:

  - personal firewall and antivirus software.

  - for more information refer to **Goals** and **Architecture** sections

  - No API sugar (left for higher level projects)

These are exposed by `require('engine.io')`:

    - Fired when the client starts the upgrade to a better transport like WebSocket.

    - Fired when the client completes the upgrade to a better transport like WebSocket.

    - Called when the write buffer is being flushed.

    - Called when the write buffer is drained

    - Called when a socket received a packet (`message`, `ping`)

      - `data`: packet data (if type is message)

    - Called before a socket sends a packet (`message`, `ping`)

    - Called when `ping` or `pong` packed is received (depends of client version)

- `server` _(Server)_: engine parent reference

- `request` _(http.IncomingMessage)_: request that originated the Socket

- `upgraded` _(Boolean)_: whether the transport has been upgraded

- `readyState` _(String)_: opening|open|closing|closed

- `transport` _(Transport)_: transport reference

    - Sends a message, performing `message = toString(arguments[0])` unless

      sending binary data, which is sent as is.

      - `String` | `Buffer` | `ArrayBuffer` | `ArrayBufferView`: a string or any object implementing `toString()`, with outgoing data, or a Buffer or ArrayBuffer with binary data. Also any ArrayBufferView can be sent as is.

      - `Object`: optional, options object

      - `Function`: optional, a callback executed when the message gets flushed out by the transport

      - `compress` (`Boolean`): whether to compress sending data. This option might be ignored and forced to be `true` when using polling. (`true`)

Exposed in the `eio` global namespace (in the browser), or by

`require('engine.io-client')` (in Node.JS).

[engine-client](http://github.com/learnboost/engine.io-client) repository.

Engine.IO is powered by [debug](http://github.com/visionmedia/debug).

In order to see all the debug output, run your app with the environment variable

To see the output from all of Engine.IO's debugging scopes you can use:

- `polling`: XHR / JSONP polling transport.

- [engine.io-conflation](https://github.com/EugenDueck/engine.io-conflation): Makes **conflation and aggregation** of messages straightforward.

The support channels for `engine.io` are the same as `socket.io`:

  - [Google Groups](http://groups.google.com/group/socket_io)

To contribute patches, run tests or benchmarks, make sure to clone the

git clone git://github.com/LearnBoost/engine.io.git

Tests run with `npm test`. It runs the server tests that are aided by

		{
		"name": "engine.io",
		"version": "6.4.0",
		"version": "6.4.1",
		"description": "The realtime engine behind Socket.IO. Provides the foundation of a bidirectional connection between client and server",
		@@ -5,0 +5,0 @@ "type": "commonjs",

		@@ -341,2 +341,10 @@
		- `Error`: error object
		- `upgrading`
		- Fired when the client starts the upgrade to a better transport like WebSocket.
		- Arguments
		- `Object`: the transport
		- `upgrade`
		- Fired when the client completes the upgrade to a better transport like WebSocket.
		- Arguments
		- `Object`: the transport
		- `flush`
		@@ -343,0 +351,0 @@ - Called when the write buffer is being flushed.

		@@ -5,3 +5,3 @@ import { Server, AttachOptions, ServerOptions } from "./server";
		export { Server, transports, listen, attach, parser };
		export { AttachOptions, ServerOptions } from "./server";
		export type { AttachOptions, ServerOptions, BaseServer } from "./server";
		export { uServer } from "./userver";
		@@ -8,0 +8,0 @@ export { Socket } from "./socket";

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