robwormald / angular-socket-io

Socket.IO component for AngularJS

angular-socket-io

Bower Component for using AngularJS with Socket.IO, based on this.

Install

1. bower install angular-socket-io or download the zip.
2. Make sure the Socket.IO client lib is loaded. It's often served at /socket.io/socket.io.js.
3. Include the socket.js script provided by this component into your app.
4. Add btford.socket-io as a module dependency to your app.

Usage

This module exposes a socketFactory, which is an API for instantiating sockets that are integrated with Angular's digest cycle.

Making a Socket Instance

// in the top-level module of the app
angular.module('myApp', [
  'btford.socket-io',
  'myApp.MyCtrl'
]).
factory('mySocket', function (socketFactory)) {
  return socketFactory();
});

With that, you can inject your mySocket service into controllers and other serivices within your application!

Using Your Socket Instance

Building on the example above:

// in the top-level module of the app
angular.module('myApp', [
  'btford.socket-io',
  'myApp.MyCtrl'
]).
factory('mySocket', function (socketFactory)) {
  return socketFactory();
});

API

For the most part, this component works exactly like you would expect. The only API addition is socket.forward, which makes it easier to add/remove listeners in a way that works with AngularJS's scope.

socket.on / socket.addListener

Takes an event name and callback. Works just like the method of the same name from Socket.IO.

socket.removeListener

Takes an event name and callback. Works just like the method of the same name from Socket.IO.

socket.emit

Sends a message to the server. Optionally takes a callback.

Works just like the method of the same name from Socket.IO.

socket.forward

socket.forward allows you to forward the events received by Socket.IO's socket to AngularJS's event system. You can then listen to the event with $scope.$on. By default, socket-forwarded events are namespaced with socket:.

The first argument is a string or array of strings listing the event names to be forwarded. The second argument is optional, and is the scope on which the events are to be broadcast. If an argument is not provided, it defaults to $rootScope. As a reminder, broadcasted events are propagated down to descendant scopes.

Examples

An easy way to make socket error events available across your app:

// in the top-level module of the app
angular.module('myApp', [
  'btford.socket-io',
  'myApp.MyCtrl'
]).
factory('mySocket', function (socketFactory)) {
  var mySocket = socketFactory();
  mySocket.forward('error');
  return mySocket;
});

// in one of your controllers
angular.module('myApp.MyCtrl', []).
  controller('MyCtrl', function ($scope) {
    $scope.$on('socket:error', function (ev, data) {

    });
  });

Avoid duplicating event handlers when a user navigates back and forth between routes:

angular.module('myMod', ['btford.socket-io']).
  controller('MyCtrl', function ($scope, socket) {
    socket.forward('someEvent', $scope);
    $scope.$on('socket:someEvent', function (ev, data) {
      $scope.theData = data;
    });
  });

socketFactory({ ioSocket: }}

This option allows you to provide the socket service with a Socket.IO socket object to be used internally. This is useful if you want to connect on a different path, or need to hold a reference to the Socket.IO socket object for use elsewhere.

angular.module('myApp', [
  'btford.socket-io'
]).
factory('mySocket', function (socketFactory)) {
  var myIoSocket = io.connect('/some/path');

  mySocket = socketFactory({
    ioSocket: myIoSocket
  });

  return mySocket;
});

socketFactory({ scope: })

This option allows you to set the scope on which $broadcast is forwarded to when using the forward method. It defaults to $rootScope.

socketFactory({ prefix: })

The default prefix is socket:.

Example

To remove the prefix:

angular.module('myApp', [
  'btford.socket-io'
]).
config(function (socketProvider) {
  socketProvider.prefix('');
});

Migrating from 0.2 to 0.3

angular-socket-io version 0.3 changes X to make fewer assumptions about the lifecycle of the socket. Previously, the assumption was that your application has a single socket created at config time. While this holds for most apps I've seen, there's no reason you shouldn't be able to lazily create sockets, or have multiple connections.

In 0.2, angular-socket-io exposed a socket service. In 0.3, it instead exposes a socketFactory service which returns socket instances. Thus, getting the old API is as simple as making your own socket service with socketFactory. The examples below demonstrate how to do this.

Simple Example

In most cases, adding the following to your app should suffice:

// ...
factory('socket', function (socketFactory)) {
  return socketFactory();
});
// ...

Example with Configuration

Before:

angular.module('myApp', [
  'btford.socket-io'
]).
config(function (socketProvider) {
  socketProvider.prefix('foo~');
  socketProvider.ioSocket(io.connect('/some/path'));
}).
controller('MyCtrl', function (socket) {
  socket.on('foo~bar', function () {
    $scope.bar = true;
  });
});

After:

angular.module('myApp', [
  'btford.socket-io'
]).
factory('socket', function (socketFactory) {
  return socketFactory({
    prefix: 'foo~',
    ioSocket: io.connect('/some/path')
  });
}).
controller('MyCtrl', function (socket) {
  socket.on('foo~bar', function () {
    $scope.bar = true;
  });
});

See Also

• ngSocket

License

MIT