Pusher PHP Library

PHP library for interacting with the Pusher HTTP API.

Register at https://pusher.com and use the application credentials within your app as shown below.

Installation

You can get the Pusher PHP library via a composer package called pusher-php-server. See https://packagist.org/packages/pusher/pusher-php-server

$ composer require pusher/pusher-php-server

Or add to composer.json:

"require": {
    "pusher/pusher-php-server": "^2.2"
}

and then run composer update.

Or you can clone or download the library files.

We recommend you use composer.

Pusher constructor

Use the credentials from your Pusher application to create a new Pusher instance.

$app_id = 'YOUR_APP_ID';
$app_key = 'YOUR_APP_KEY';
$app_secret = 'YOUR_APP_SECRET';

$pusher = new Pusher( $app_key, $app_secret, $app_id );

A fourth parameter $options parameter can also be passed. The available options are:

• scheme - e.g. http or https
• host - the host e.g. api.pusherapp.com. No trailing forward slash.
• port - the http port
• timeout - the HTTP timeout
• encrypted - quick option to use scheme of https and port 443.
• cluster - specify the cluster where the application is running from.

For example, by default calls will be made over a non-encrypted connection. To change this to make calls over HTTPS use:

$pusher = new Pusher( $app_key, $app_secret, $app_id, array( 'encrypted' => true ) );

Note: The $options parameter was introduced in version 2.2.0 of the library. Previously additional parameters could be passed for each option, but this was becoming unwieldy. However, backwards compatibility has been maintained.

Note: The host option overrides the cluster option!

Publishing/Triggering events

To trigger an event on one or more channels use the trigger function.

A single channel

$pusher->trigger( 'my-channel', 'my_event', 'hello world' );

Multiple channels

$pusher->trigger( [ 'channel-1', 'channel-2' ], 'my_event', 'hello world' );

Arrays

Objects are automatically converted to JSON format:

$array['name'] = 'joe';
$array['message_count'] = 23;

$pusher->trigger('my_channel', 'my_event', $array);

The output of this will be:

"{'name': 'joe', 'message_count': 23}"

Socket id

In order to avoid duplicates you can optionally specify the sender's socket id while triggering an event (https://pusher.com/docs/duplicates):

$pusher->trigger('my-channel','event','data','socket_id');

JSON format

If your data is already encoded in JSON format, you can avoid a second encoding step by setting the sixth argument true, like so:

$pusher->trigger('my-channel', 'event', 'data', null, false, true)

Authenticating Private channels

To authorise your users to access private channels on Pusher, you can use the socket_auth function:

$pusher->socket_auth('my-channel','socket_id');

Authenticating Presence channels

Using presence channels is similar to private channels, but you can specify extra data to identify that particular user:

$pusher->presence_auth('my-channel','socket_id', 'user_id', 'user_info');

Presence example

First set this variable in your JS app:

Pusher.channel_auth_endpoint = '/presence_auth.php';

Next, create the following in presence_auth.php:

<?php
if (isset($_SESSION['user_id'])) {
  $stmt = $pdo->prepare("SELECT * FROM `users` WHERE id = :id");
  $stmt->bindValue(':id', $_SESSION['user_id'], PDO::PARAM_INT);
  $stmt->execute();
  $user = $stmt->fetch();
} else {
  die('aaargh, no-one is logged in')
}

header('Content-Type: application/json');

$pusher = new Pusher($key, $secret, $app_id);
$presence_data = array('name' => $user['name']);

echo $pusher->presence_auth($_POST['channel_name'], $_POST['socket_id'], $user['id'], $presence_data);

Note: this assumes that you store your users in a table called users and that those users have a name column. It also assumes that you have a login mechanism that stores the user_id of the logged in user in the session.

Application State Queries

Get information about a channel

$pusher->get_channel_info( $name );

It's also possible to get information about a channel from the Pusher REST API.

$info = $pusher->get_channel_info('channel-name');
$channel_occupied = $info->occupied;

For presence channels you can also query the number of distinct users currently subscribed to this channel (a single user may be subscribed many times, but will only count as one):

$info = $pusher->get_channel_info('presence-channel-name', array('info' => 'user_count'));
$user_count = $info->user_count;

If you have enabled the ability to query the subscription_count (the number of connections currently subscribed to this channel) then you can query this value as follows:

$info = $pusher->get_channel_info('presence-channel-name', array('info' => 'subscription_count'));
$subscription_count = $info->subscription_count;

Get a list of application channels

$pusher->get_channels()

It's also possible to get a list of channels for an application from the Pusher REST API.

$result = $pusher->get_channels();
$channel_count = count($result->channels); // $channels is an Array

Get a filtered list of application channels

$pusher->get_channels( array( 'filter_by_prefix' => 'some_filter' ) )

It's also possible to get a list of channels based on their name prefix. To do this you need to supply an $options parameter to the call. In the following example the call will return a list of all channels with a 'presence-' prefix. This is idea for fetching a list of all presence channels.

$results = $pusher->get_channels( array( 'filter_by_prefix' => 'presence-') );
$channel_count = count($result->channels); // $channels is an Array

This can also be achieved using the generic pusher->get function:

$pusher->get( '/channels', array( 'filter_by_prefix' => 'presence-' ) );

Get user information from a presence channel

$response = $pusher->get( '/channels/presence-channel-name/users' )

The $response is in the format:

Array
(
    [body] => {"users":[{"id":"a_user_id"}]}
    [status] => 200
    [result] => Array
        (
            [users] => Array
                (
                    [0] => Array
                        (
                            [id] => a_user_id
                        )
                    /* Additional users */
                )
        )
)

Generic get function

$pusher->get( $path, $params );

Used to make GET queries against the Pusher REST API. Handles authentication.

Response is an associative array with a result index. The contents of this index is dependent on the REST method that was called. However, a status property to allow the HTTP status code is always present and a result property will be set if the status code indicates a successful call to the API.

$response = $pusher->get( '/channels' );
$http_status_code = $response[ 'status' ];
$result = $response[ 'result' ];

Debugging & Logging

The best way to debug your applications interaction with server is to set a logger for the library so you can see the internal workings within the library and interactions with the Pusher service.

You set up logging by passing an object with a log function to the pusher->set_logger function:

class MyLogger {
  public function log( $msg ) {
    print_r( $msg . "\n" );
  }
}

$pusher->set_logger( new MyLogger() );

If you use the above example in code executed from the console/terminal the debug information will be output there. If you use this within a web app then the output will appear within the generated app output e.g. HTML.

Running the tests

Requires phpunit.

• Got to the tests directory
• Rename config.example.php and replace the values with valid Pusher credentials or create environment variables.
• Some tests require a client to be connected to the app you defined in the config; you can do this by opening https://app.pusher.com/apps/<YOUR_TEST_APP_ID>/api_access in the browser
• Execute phpunit . to run all the tests.

Framework Integrations

• Laravel 4 - https://github.com/artdarek/pusherer
• Laravel 5 - https://github.com/vinkla/pusher

License

Copyright 2014, Pusher. Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php

Copyright 2010, Squeeks. Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php