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