Sugar Events
This is a event system for the PHP Fat-free Framework. Here is what's included so far:
- emit events from any point of your app
- attach one or multiple listeners to an event
- a listener (hook) can have a priority order
- additional options for listeners
- local events on specific objects
- send payload and context data with an event
- sub-events and event propagation
- stop the event chain
- works with F3 v3.5 and PHP v7.2+
This event system is experimental, so please handle with care.
Installation
-
Method 1: use composer:
composer require ikkez/f3-events -
Method 2: copy the
lib/event.phpfile into your F3lib/directory or another directory that is known to the AUTOLOADER
How does it work:
The Event class is a child of Prefab, so you can get it everywhere like this:
// fetch the global Event instance
$events = \Sugar\Event::instance();Define a listener / hook:
// typical F3 callstring
$events->on('user_login', 'Notification->user_login');
// or with callbacks
$events->on('user_login', function(){
// ...
});
// or with callables
$events->on('user_login', [$this,'method']); Send an event:
$events->emit('user_login');Send payload with event:
$events->on('user_login', function($username){
\Logger::log($username.' logged in');
});
$events->emit('user_login', 'freakazoid');Multiple listeners with prioritization:
$events->on('user_login', function($username){
\Logger::log($username.' logged in');
}, 10); // 10 is default priority
$events->on('user_login', function(){
\Flash::addMessage('You have logged in successfully');
}, 20); // 20 is a higher priority and is called first
$events->emit('user_login', 'freakazoid');Stop the event chain:
$events->on('user_login', function($username){
\Logger::log($username.' logged in');
});
$events->on('user_login', function(){
\Flash::addMessage('You have logged in successfully');
return false; // <-- skip any other listener on the same event
}, 20);
$events->emit('user_login', 'freakazoid');
// The logger event isn't called anymoreAdditional event context data:
$events->on('user_login', function($username,$context){
if ($context['lang'] == 'en')
\Flash::addMessage('You have logged in successfully');
elseif($context['lang'] == 'de')
\Flash::addMessage('Du hast dich erfolgreich angemeldet');
});
$events->emit('user_login', 'freakazoid', array('lang'=>'en'));Additional listener options:
$events->on('user_login', function($username,$context,$event){
\Flash::addMessage('You have logged in successfully', $event['options']['type']);
}, 20, array('type'=>'success'));I think that are the basic usage samples that could fit the most cases. Nevertheless here are some more advanced things you can do:
Filter payload:
$events->on('get_total', function($basket){
$sum = 0;
foreach($basket as $prod) {
$sum+=$prod;
}
return $sum;
});
$products = array(
'a' => 2,
'b' => 8,
'c' => 15,
);
$sum = $events->emit('get_total',$products);
echo $sum; // 25Add a sub-event. These are called after the parent event. Listeners and sub-events follow the FIFO processing, which means the first that is registered is the first that will be called.
$events->on('get_total.tax', function($sum){
return $sum+($sum*0.2);
});
$events->on('get_total.shipping', function($sum){
return $sum+5;
});
$sum = $events->emit('get_total',$products);
echo $sum; // 35Remove hooks:
$events->off('get_total.tax');
$sum = $events->emit('get_total',$products);
echo $sum; // 30There is also a mechanic build in which supports local events for mappers and such, which have implemented it:
$user = new \Model\User();
$events->watch($user)->on('update.email','\Mailer->sendEmailActivationLink');Unit tests
to add the tests to your local F3 test-bench, add this:
// Event Tests
$f3->concat('AUTOLOAD', ',path/to/f3-events/test/');
\Sugar\EventTests::init();License
You are allowed to use this plugin under the terms of the GNU General Public License version 3 or later.
Copyright (C) 2017 Christian Knuth [ikkez]