friendica/src/Core/Hook.php
2019-01-21 10:35:51 -05:00

229 lines
6.0 KiB
PHP

<?php
/**
* @file src/Core/Hook.php
*/
namespace Friendica\Core;
use Friendica\App;
use Friendica\BaseObject;
use Friendica\Database\DBA;
/**
* Some functions to handle hooks
*/
class Hook extends BaseObject
{
/**
* Array of registered hooks
*
* Format:
* [
* ["<hook name>"] => [
* 0 => "<hook file>",
* 1 => "<hook function name>"
* ],
* ...
* ]
*
* @var array
*/
private static $hooks = [];
/**
* Load hooks
*/
public static function loadHooks()
{
self::$hooks = [];
$stmt = DBA::select('hook', ['hook', 'file', 'function'], [], ['order' => ['priority' => 'desc', 'file']]);
while ($hook = DBA::fetch($stmt)) {
self::add($hook['hook'], $hook['file'], $hook['function']);
}
DBA::close($stmt);
}
/**
* @brief Adds a new hook to the hooks array.
*
* This function is meant to be called by modules on each page load as it works after loadHooks has been called.
*
* @param string $hook
* @param string $file
* @param string $function
*/
public static function add($hook, $file, $function)
{
if (!array_key_exists($hook, self::$hooks)) {
self::$hooks[$hook] = [];
}
self::$hooks[$hook][] = [$file, $function];
}
/**
* @brief Registers a hook.
*
* This function is meant to be called once when an addon is enabled for example as it doesn't add to the current hooks.
*
* @param string $hook the name of the hook
* @param string $file the name of the file that hooks into
* @param string $function the name of the function that the hook will call
* @param int $priority A priority (defaults to 0)
* @return mixed|bool
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function register($hook, $file, $function, $priority = 0)
{
$file = str_replace(self::getApp()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
$condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
if (DBA::exists('hook', $condition)) {
return true;
}
$result = DBA::insert('hook', ['hook' => $hook, 'file' => $file, 'function' => $function, 'priority' => $priority]);
return $result;
}
/**
* Unregisters a hook.
*
* @param string $hook the name of the hook
* @param string $file the name of the file that hooks into
* @param string $function the name of the function that the hook called
* @return boolean
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function unregister($hook, $file, $function)
{
$relative_file = str_replace(self::getApp()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
// This here is only needed for fixing a problem that existed on the develop branch
$condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
DBA::delete('hook', $condition);
$condition = ['hook' => $hook, 'file' => $relative_file, 'function' => $function];
$result = DBA::delete('hook', $condition);
return $result;
}
/**
* Returns the list of callbacks for a single hook
*
* @param string $name Name of the hook
* @return array
*/
public static function getByName($name)
{
$return = [];
if (isset(self::$hooks[$name])) {
$return = self::$hooks[$name];
}
return $return;
}
/**
* @brief Forks a hook.
*
* Use this function when you want to fork a hook via the worker.
*
* @param integer $priority of the hook
* @param string $name of the hook to call
* @param mixed $data to transmit to the callback handler
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function fork($priority, $name, $data = null)
{
if (array_key_exists($name, self::$hooks)) {
foreach (self::$hooks[$name] as $hook) {
// Call a hook to check if this hook call needs to be forked
if (array_key_exists('hook_fork', self::$hooks)) {
$hookdata = ['name' => $name, 'data' => $data, 'execute' => true];
foreach (self::$hooks['hook_fork'] as $fork_hook) {
if ($hook[0] != $fork_hook[0]) {
continue;
}
self::callSingle(self::getApp(), 'hook_fork', $fork_hook, $hookdata);
}
if (!$hookdata['execute']) {
continue;
}
}
Worker::add($priority, 'ForkHook', $name, $hook, $data);
}
}
}
/**
* @brief Calls a hook.
*
* Use this function when you want to be able to allow a hook to manipulate
* the provided data.
*
* @param string $name of the hook to call
* @param string|array &$data to transmit to the callback handler
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function callAll($name, &$data = null)
{
if (array_key_exists($name, self::$hooks)) {
foreach (self::$hooks[$name] as $hook) {
self::callSingle(self::getApp(), $name, $hook, $data);
}
}
}
/**
* @brief Calls a single hook.
*
* @param App $a
* @param string $name of the hook to call
* @param array $hook Hook data
* @param string|array &$data to transmit to the callback handler
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function callSingle(App $a, $name, $hook, &$data = null)
{
// Don't run a theme's hook if the user isn't using the theme
if (strpos($hook[0], 'view/theme/') !== false && strpos($hook[0], 'view/theme/' . $a->getCurrentTheme()) === false) {
return;
}
@include_once($hook[0]);
if (function_exists($hook[1])) {
$func = $hook[1];
$func($a, $data);
} else {
// remove orphan hooks
$condition = ['hook' => $name, 'file' => $hook[0], 'function' => $hook[1]];
DBA::delete('hook', $condition, ['cascade' => false]);
}
}
/**
* Checks if an app_menu hook exist for the provided addon name.
* Return true if the addon is an app
*
* @param string $name Name of the addon
* @return boolean
*/
public static function isAddonApp($name)
{
if (array_key_exists('app_menu', self::$hooks)) {
foreach (self::$hooks['app_menu'] as $hook) {
if ($hook[0] == 'addon/' . $name . '/' . $name . '.php') {
return true;
}
}
}
return false;
}
}