src/Core/Hook.php

   1 <?php
   2 /**
   3  * @file src/Core/Hook.php
   4  */
   5 namespace Friendica\Core;
   6
   7 use Friendica\App;
   8 use Friendica\BaseObject;
   9 use Friendica\Database\DBA;
  10
  11 /**
  12  * Some functions to handle hooks
  13  */
  14 class Hook extends BaseObject
  15 {
  16         /**
  17          * Array of registered hooks
  18          *
  19          * Format:
  20          * [
  21          *              ["<hook name>"] => [
  22          *                      0 => "<hook file>",
  23          *                      1 => "<hook function name>"
  24          *              ],
  25          *              ...
  26          * ]
  27          *
  28          * @var array
  29          */
  30         private static $hooks = [];
  31
  32         /**
  33          * Load hooks
  34          */
  35         public static function loadHooks()
  36         {
  37                 self::$hooks = [];
  38                 $stmt = DBA::select('hook', ['hook', 'file', 'function'], [], ['order' => ['priority' => 'desc', 'file']]);
  39
  40                 while ($hook = DBA::fetch($stmt)) {
  41                         if (!array_key_exists($hook['hook'], self::$hooks)) {
  42                                 self::$hooks[$hook['hook']] = [];
  43                         }
  44                         self::$hooks[$hook['hook']][] = [$hook['file'], $hook['function']];
  45                 }
  46                 DBA::close($stmt);
  47         }
  48
  49         /**
  50          * Registers a hook.
  51          *
  52          * @param string $hook     the name of the hook
  53          * @param string $file     the name of the file that hooks into
  54          * @param string $function the name of the function that the hook will call
  55          * @param int    $priority A priority (defaults to 0)
  56          * @return mixed|bool
  57          */
  58         public static function register($hook, $file, $function, $priority = 0)
  59         {
  60                 $file = str_replace(self::getApp()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
  61
  62                 $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
  63                 if (DBA::exists('hook', $condition)) {
  64                         return true;
  65                 }
  66
  67                 $result = DBA::insert('hook', ['hook' => $hook, 'file' => $file, 'function' => $function, 'priority' => $priority]);
  68
  69                 return $result;
  70         }
  71
  72         /**
  73          * Unregisters a hook.
  74          *
  75          * @param string $hook     the name of the hook
  76          * @param string $file     the name of the file that hooks into
  77          * @param string $function the name of the function that the hook called
  78          * @return boolean
  79          */
  80         public static function unregister($hook, $file, $function)
  81         {
  82                 $relative_file = str_replace(self::getApp()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
  83
  84                 // This here is only needed for fixing a problem that existed on the develop branch
  85                 $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
  86                 DBA::delete('hook', $condition);
  87
  88                 $condition = ['hook' => $hook, 'file' => $relative_file, 'function' => $function];
  89                 $result = DBA::delete('hook', $condition);
  90                 return $result;
  91         }
  92
  93         /**
  94          * Returns the list of callbacks for a single hook
  95          *
  96          * @param  string $name Name of the hook
  97          * @return array
  98          */
  99         public static function getByName($name)
 100         {
 101                 $return = [];
 102
 103                 if (isset(self::$hooks[$name])) {
 104                         $return = self::$hooks[$name];
 105                 }
 106
 107                 return $return;
 108         }
 109
 110         /**
 111          * @brief Forks a hook.
 112          *
 113          * Use this function when you want to fork a hook via the worker.
 114          *
 115          * @param integer $priority of the hook
 116          * @param string  $name     of the hook to call
 117          * @param mixed   $data     to transmit to the callback handler
 118          */
 119         public static function fork($priority, $name, $data = null)
 120         {
 121                 if (array_key_exists($name, self::$hooks)) {
 122                         foreach (self::$hooks[$name] as $hook) {
 123                                 Worker::add($priority, 'ForkHook', $name, $hook, $data);
 124                         }
 125                 }
 126         }
 127
 128         /**
 129          * @brief Calls a hook.
 130          *
 131          * Use this function when you want to be able to allow a hook to manipulate
 132          * the provided data.
 133          *
 134          * @param string       $name  of the hook to call
 135          * @param string|array &$data to transmit to the callback handler
 136          */
 137         public static function callAll($name, &$data = null)
 138         {
 139                 if (array_key_exists($name, self::$hooks)) {
 140                         foreach (self::$hooks[$name] as $hook) {
 141                                 self::callSingle(self::getApp(), $name, $hook, $data);
 142                         }
 143                 }
 144         }
 145
 146         /**
 147          * @brief Calls a single hook.
 148          *
 149          * @param App $a
 150          * @param string         $name of the hook to call
 151          * @param array          $hook Hook data
 152          * @param string|array   &$data to transmit to the callback handler
 153          */
 154         public static function callSingle(App $a, $name, $hook, &$data = null)
 155         {
 156                 // Don't run a theme's hook if the user isn't using the theme
 157                 if (strpos($hook[0], 'view/theme/') !== false && strpos($hook[0], 'view/theme/' . $a->getCurrentTheme()) === false) {
 158                         return;
 159                 }
 160
 161                 @include_once($hook[0]);
 162                 if (function_exists($hook[1])) {
 163                         $func = $hook[1];
 164                         $func($a, $data);
 165                 } else {
 166                         // remove orphan hooks
 167                         $condition = ['hook' => $name, 'file' => $hook[0], 'function' => $hook[1]];
 168                         DBA::delete('hook', $condition, ['cascade' => false]);
 169                 }
 170         }
 171
 172         /**
 173          * Checks if an app_menu hook exist for the provided addon name.
 174          * Return true if the addon is an app
 175          *
 176          * @param string $name Name of the addon
 177          * @return boolean
 178          */
 179         public static function isAddonApp($name)
 180         {
 181                 if (array_key_exists('app_menu', self::$hooks)) {
 182                         foreach (self::$hooks['app_menu'] as $hook) {
 183                                 if ($hook[0] == 'addon/' . $name . '/' . $name . '.php') {
 184                                         return true;
 185                                 }
 186                         }
 187                 }
 188
 189                 return false;
 190         }
 191 }