Status: Looking for feedback about new API changes
An AngularJS 1.x WebSocket service for connecting client applications to servers.
How do I add this to my project?
You can download angular-websocket by:
Usage
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.8/angular.min.js"></script>
<script src="bower_components/angular-websocket/angular-websocket.js"></script>
<section ng-controller="SomeController">
<ul>
<li ng-repeat="data in MyData.collection track by $index">
{{ data }}
</li>
</ul>
</section>
<script>
angular.module('YOUR_APP', [
'ngWebSocket' // you may also use 'angular-websocket' if you prefer
])
// WebSocket works as well
.factory('MyData', function($websocket) {
// Open a WebSocket connection
var dataStream = $websocket('wss://website.com/data');
var collection = [];
dataStream.onMessage(function(message.data) {
collection.push(JSON.parse(message.data));
});
var methods = {
collection: collection,
get: function() {
dataStream.send(JSON.stringify({ action: 'get' }));
}
};
return methods;
})
.controller('SomeController', function (MyData) {
$scope.MyData = MyData;
});
</script>API
Factory: $websocket (in module ngWebSocket)
returns instance of $Websocket
Methods
| name | arguments | description |
|---|---|---|
| $websocket constructor |
url:String | Creates and opens a WebSocket instance. var ws = $websocket('ws://foo');
|
| send | data:String,Object returns | Adds data to a queue, and attempts to send if socket is ready. Accepts string or object, and will stringify objects before sending to socket. |
| onMessage | callback:Function options{filter:String,RegExp, autoApply:Boolean=true} |
Register a callback to be fired on every message received from the websocket, or optionally just when the message's data property matches the filter provided in the options object. Each message handled will safely call $rootScope.$digest() unless autoApply is set to `false in the options. Callback gets called with a MessageEvent object. |
| onOpen | callback:Function | Function to be executed each time a socket connection is opened for this instance. |
| onClose | callback:Function | Function to be executed each time a socket connection is closed for this instance. |
| onError | callback:Function | Function to be executed each time a socket connection has an Error for this instance. |
| close | force:Boolean:optional | Close the underlying socket, as long as no data is still being sent from the client. Optionally force close, even if data is still being sent, by passing true as the force parameter. To check if data is being sent, read the value of socket.bufferedAmount. |
Properties
| name | type | description |
|---|---|---|
| socket | window.WebSocket | WebSocket instance. |
| sendQueue | Array | Queue of send calls to be made on socket when socket is able to receive data. List is populated by calls to the send method, but this array can be spliced if data needs to be manually removed before it's been sent to a socket. Data is removed from the array after it's been sent to the socket. |
| onOpenCallbacks | Array | List of callbacks to be executed when the socket is opened, initially or on re-connection after broken connection. Callbacks should be added to this list through the onOpen method. |
| onMessageCallbacks | Array | List of callbacks to be executed when a message is received from the socket. Callbacks should be added via the onMessage method. |
| readyState | Number:readonly | Returns either the readyState value from the underlying WebSocket instance, or a proprietary value representing the internal state of the lib, e.g. if the lib is in a state of re-connecting. |
| initialTimeout | Number | The initial timeout, should be set at the outer limits of expected response time for the service. For example, if your service responds in 1ms on average but in 10ms for 99% of requests, then set to 10ms. |
| maxTimeout | Number | Should be as low as possible to keep your customers happy, but high enough that the system can definitely handle requests from all clients at that sustained rate. |
CancelablePromise
This type is returned from the send() instance method of $websocket, inherits from $q.defer().promise.
Methods
| name | arguments | description |
|---|---|---|
| cancel | Alias to deferred.reject(), allows preventing an unsent message from being sent to socket for any arbitrary reason. |
|
| then | resolve:Function, reject:Function | Resolves when message has been passed to socket, presuming the socket has a readyState of 1. Rejects if the socket is hopelessly disconnected now or in the future (i.e. the library is no longer attempting to reconnect). All messages are immediately rejected when the library has determined that re-establishing a connection is unlikely. |
Service: $websocketBackend (in module ngWebSocketMock)
Similar to httpBackend mock in AngularJS's ngMock module
Methods
| name | arguments | description |
|---|---|---|
| flush | Executes all pending requests | |
| expectConnect | url:String | Specify the url of an expected WebSocket connection |
| expectClose | Expect "close" to be called on the WebSocket | |
| expectSend | msg:String | Expectation of send to be called, with required message |
| verifyNoOutstandingExpectation | Makes sure all expectations have been satisfied, should be called in afterEach | |
| verifyNoOutstandingRequest | Makes sure no requests are pending, should be called in afterEach |
Frequently asked questions
- Q.: What if the browser doesn't support WebSockets?
- A.: This module will not help; it does not have a fallback story for browsers that do not support WebSockets. Please check your browser target support here and to include fallback support.
Development
$ npm install
$ bower installChangelog
Unit Tests
$ npm test Run karma in Chrome, Firefox, and Safari
Manual Tests
In the project root directory open index.html in the example folder
Distribute
$ npm run dist Builds files with uglifyjs
TODO
- Allow JSON if object is sent
- Allow more control over $digest cycle per WebSocket instance
