This is the client for Engine.IO, the implementation of transport-based cross-browser/cross-device bi-directional communication layer for Socket.IO.
You can find an engine.io.js
file in this repository, which is a
standalone build you can use as follows:
<script src="/path/to/engine.io.js"></script>
<script>
// eio = Socket
var socket = eio('ws://localhost');
socket.on('open', function(){
socket.on('message', function(data){});
socket.on('close', function(){});
});
</script>
Engine.IO is a commonjs module, which means you can include it by using
require
on the browser and package using browserify:
-
install the client package
$ npm install engine.io-client
-
write your app code
var socket = require('engine.io-client')('ws://localhost'); socket.on('open', function(){ socket.on('message', function(data){}); socket.on('close', function(){}); });
-
build your app bundle
$ browserify app.js > bundle.js
-
include on your page
<script src="/path/to/bundle.js"></script>
<script src="/path/to/engine.io.js"></script>
<script>
var socket = new eio.Socket('ws://localhost/');
socket.binaryType = 'blob';
socket.on('open', function () {
socket.send(new Int8Array(5));
socket.on('message', function(blob){});
socket.on('close', function(){ });
});
</script>
Add engine.io-client
to your package.json
and then:
var socket = require('engine.io-client')('ws://localhost');
socket.on('open', function(){
socket.on('message', function(data){});
socket.on('close', function(){});
});
- Lightweight
- Runs on browser and node.js seamlessly
- Transports are independent of
Engine
- Easy to debug
- Easy to unit test
- Runs inside HTML5 WebWorker
- Can send and receive binary data
- Receives as ArrayBuffer or Blob when in browser, and Buffer or ArrayBuffer in Node
- When XHR2 or WebSockets are used, binary is emitted directly. Otherwise binary is encoded into base64 strings, and decoded when binary types are supported.
- With browsers that don't support ArrayBuffer, an object { base64: true,
data: dataAsBase64String } is emitted on the
message
event.
The client class. Mixes in Emitter.
Exposed as eio
in the browser standalone build.
protocol
(Number): protocol revision numberbinaryType
(String) : can be set to 'arraybuffer' or 'blob' in browsers, andbuffer
orarraybuffer
in Node. Blob is only used in browser if it's supported.
open
- Fired upon successful connection.
message
- Fired when data is received from the server.
- Arguments
String
|ArrayBuffer
: utf-8 encoded data or ArrayBuffer containing binary data
close
- Fired upon disconnection. In compliance with the WebSocket API spec, this event may be
fired even if the
open
event does not occur (i.e. due to connection error orclose()
).
- Fired upon disconnection. In compliance with the WebSocket API spec, this event may be
fired even if the
error
- Fired when an error occurs.
flush
- Fired upon completing a buffer flush
drain
- Fired after
drain
event of transport if writeBuffer is empty
- Fired after
upgradeError
- Fired if an error occurs with a transport we're trying to upgrade to.
upgrade
- Fired upon upgrade success, after the new transport is set
- constructor
- Initializes the client
- Parameters
String
uriObject
: optional, options object
- Options
agent
(http.Agent
):http.Agent
to use, defaults tofalse
(NodeJS only)upgrade
(Boolean
): defaults to true, whether the client should try to upgrade the transport from long-polling to something better.forceJSONP
(Boolean
): forces JSONP for polling transport.jsonp
(Boolean
): determines whether to use JSONP when necessary for polling. If disabled (by settings to false) an error will be emitted (saying "No transports available") if no other transports are available. If another transport is available for opening a connection (e.g. WebSocket) that transport will be used instead.forceBase64
(Boolean
): forces base 64 encoding for polling transport even when XHR2 responseType is available and WebSocket even if the used standard supports binary.timestampRequests
(Boolean
): whether to add the timestamp with each transport request. Note: this is ignored if the browser is IE or Android, in which case requests are always stamped (false
)timestampParam
(String
): timestamp parameter (t
)policyPort
(Number
): port the policy server listens on (843
)path
(String
): path to connect to, default is/engine.io
transports
(Array
): a list of transports to try (in order). Defaults to['polling', 'websocket']
.Engine
always attempts to connect directly with the first one, provided the feature detection test for it passes.rememberUpgrade
(Boolean
): defaults to false. If true and if the previous websocket connection to the server succeeded, the connection attempt will bypass the normal upgrade process and will initially try websocket. A connection attempt following a transport error will use the normal upgrade process. It is recommended you turn this on only when using SSL/TLS connections, or if you know that your network does not block websockets.
send
- Sends a message to the server
- Parameters
String
|ArrayBuffer
|ArrayBufferView
|Blob
: data to sendFunction
: optional, callback upondrain
close
- Disconnects the client.
The transport class. Private. Inherits from EventEmitter.
poll
: emitted by polling transports upon starting a new requestpollComplete
: emitted by polling transports upon completing a requestdrain
: emitted by polling transports upon a buffer drain
engine.io-client
is used to test
engine. Running the engine.io
test suite ensures the client works and vice-versa.
Browser tests are run using zuul. You can run the tests locally using the following command.
./node_modules/.bin/zuul --local 8080 -- test/index.js
Additionally, engine.io-client
has a standalone test suite you can run
with make test
which will run node.js and browser tests. You must have zuul setup with
a saucelabs account.
The support channels for engine.io-client
are the same as socket.io
:
- irc.freenode.net #socket.io
- Google Groups
- Website
To contribute patches, run tests or benchmarks, make sure to clone the repository:
git clone git://github.com/automattic/engine.io-client.git
Then:
cd engine.io-client
npm install
See the Tests
section above for how to run tests before submitting any patches.
MIT - Copyright (c) 2014 Automattic, Inc.