139 lines
4.6 KiB
PHP
139 lines
4.6 KiB
PHP
<?php
|
|
// This file is part of GNU social - https://www.gnu.org/software/social
|
|
//
|
|
// GNU social is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Affero General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// GNU social is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Affero General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Affero General Public License
|
|
// along with GNU social. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
defined('GNUSOCIAL') || die();
|
|
|
|
/**
|
|
* Class for events
|
|
*
|
|
* This "class" two static functions for managing events in the StatusNet code.
|
|
*
|
|
* @category Event
|
|
* @package GNU social
|
|
* @author Evan Prodromou <evan@status.net>
|
|
* @copyright 2010-2019 Free Software Foundation, Inc http://www.fsf.org
|
|
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
|
|
*
|
|
* @todo Define a system for using Event instances
|
|
*/
|
|
class Event {
|
|
|
|
/* Global array of hooks, mapping eventname => array of callables */
|
|
|
|
protected static $_handlers = array();
|
|
|
|
/**
|
|
* Add an event handler
|
|
*
|
|
* To run some code at a particular point in StatusNet processing.
|
|
* Named events include receiving an XMPP message, adding a new notice,
|
|
* or showing part of an HTML page.
|
|
*
|
|
* The arguments to the handler vary by the event. Handlers can return
|
|
* two possible values: false means that the event has been replaced by
|
|
* the handler completely, and no default processing should be done.
|
|
* Non-false means successful handling, and that the default processing
|
|
* should succeed. (Note that this only makes sense for some events.)
|
|
*
|
|
* Handlers can also abort processing by throwing an exception; these will
|
|
* be caught by the closest code and displayed as errors.
|
|
*
|
|
* @param string $name Name of the event
|
|
* @param callable $handler Code to run
|
|
*
|
|
* @return void
|
|
*/
|
|
|
|
public static function addHandler($name, $handler) {
|
|
if (array_key_exists($name, Event::$_handlers)) {
|
|
Event::$_handlers[$name][] = $handler;
|
|
} else {
|
|
Event::$_handlers[$name] = array($handler);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Handle an event
|
|
*
|
|
* Events are any point in the code that we want to expose for admins
|
|
* or third-party developers to use.
|
|
*
|
|
* We pass in an array of arguments (including references, for stuff
|
|
* that can be changed), and each assigned handler gets run with those
|
|
* arguments. Exceptions can be thrown to indicate an error.
|
|
*
|
|
* @param string $name Name of the event that's happening
|
|
* @param array $args Arguments for handlers
|
|
*
|
|
* @return boolean flag saying whether to continue processing, based
|
|
* on results of handlers.
|
|
*/
|
|
|
|
public static function handle($name, array $args=array()) {
|
|
$result = null;
|
|
if (array_key_exists($name, Event::$_handlers)) {
|
|
foreach (Event::$_handlers[$name] as $handler) {
|
|
$result = call_user_func_array($handler, $args);
|
|
if ($result === false) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
return ($result !== false);
|
|
}
|
|
|
|
/**
|
|
* Check to see if an event handler exists
|
|
*
|
|
* Look to see if there's any handler for a given event, or narrow
|
|
* by providing the name of a specific plugin class.
|
|
*
|
|
* @param string $name Name of the event to look for
|
|
* @param string $plugin Optional name of the plugin class to look for
|
|
*
|
|
* @return boolean flag saying whether such a handler exists
|
|
*
|
|
*/
|
|
|
|
public static function hasHandler($name, $plugin=null) {
|
|
if (array_key_exists($name, Event::$_handlers)) {
|
|
if (isset($plugin)) {
|
|
foreach (Event::$_handlers[$name] as $handler) {
|
|
if (get_class($handler[0]) == $plugin) {
|
|
return true;
|
|
}
|
|
}
|
|
} else {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
public static function getHandlers($name)
|
|
{
|
|
return Event::$_handlers[$name];
|
|
}
|
|
|
|
/**
|
|
* Disables any and all handlers that have been set up so far;
|
|
* use only if you know it's safe to reinitialize all plugins.
|
|
*/
|
|
public static function clearHandlers() {
|
|
Event::$_handlers = array();
|
|
}
|
|
}
|