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 use Friendica\DI;
  11 use Friendica\Util\Strings;
  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($stmt)) {
  43                         self::add($hook['hook'], $hook['file'], $hook['function']);
  44                 }
  45                 DBA::close($stmt);
  46         }
  47
  48         /**
  49          * @brief Adds a new hook to the hooks array.
  50          *
  51          * This function is meant to be called by modules on each page load as it works after loadHooks has been called.
  52          *
  53          * @param string $hook
  54          * @param string $file
  55          * @param string $function
  56          */
  57         public static function add($hook, $file, $function)
  58         {
  59                 if (!array_key_exists($hook, self::$hooks)) {
  60                         self::$hooks[$hook] = [];
  61                 }
  62                 self::$hooks[$hook][] = [$file, $function];
  63         }
  64
  65         /**
  66          * @brief Registers a hook.
  67          *
  68          * This function is meant to be called once when an addon is enabled for example as it doesn't add to the current hooks.
  69          *
  70          * @param string $hook     the name of the hook
  71          * @param string $file     the name of the file that hooks into
  72          * @param string $function the name of the function that the hook will call
  73          * @param int    $priority A priority (defaults to 0)
  74          * @return mixed|bool
  75          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  76          */
  77         public static function register($hook, $file, $function, $priority = 0)
  78         {
  79                 $file = str_replace(DI::app()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
  80
  81                 $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
  82                 if (DBA::exists('hook', $condition)) {
  83                         return true;
  84                 }
  85
  86                 $result = DBA::insert('hook', ['hook' => $hook, 'file' => $file, 'function' => $function, 'priority' => $priority]);
  87
  88                 return $result;
  89         }
  90
  91         /**
  92          * Unregisters a hook.
  93          *
  94          * @param string $hook     the name of the hook
  95          * @param string $file     the name of the file that hooks into
  96          * @param string $function the name of the function that the hook called
  97          * @return boolean
  98          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  99          */
 100         public static function unregister($hook, $file, $function)
 101         {
 102                 $relative_file = str_replace(DI::app()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
 103
 104                 // This here is only needed for fixing a problem that existed on the develop branch
 105                 $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
 106                 DBA::delete('hook', $condition);
 107
 108                 $condition = ['hook' => $hook, 'file' => $relative_file, 'function' => $function];
 109                 $result = DBA::delete('hook', $condition);
 110                 return $result;
 111         }
 112
 113         /**
 114          * Returns the list of callbacks for a single hook
 115          *
 116          * @param  string $name Name of the hook
 117          * @return array
 118          */
 119         public static function getByName($name)
 120         {
 121                 $return = [];
 122
 123                 if (isset(self::$hooks[$name])) {
 124                         $return = self::$hooks[$name];
 125                 }
 126
 127                 return $return;
 128         }
 129
 130         /**
 131          * @brief Forks a hook.
 132          *
 133          * Use this function when you want to fork a hook via the worker.
 134          *
 135          * @param integer $priority of the hook
 136          * @param string  $name     of the hook to call
 137          * @param mixed   $data     to transmit to the callback handler
 138          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 139          */
 140         public static function fork($priority, $name, $data = null)
 141         {
 142                 if (array_key_exists($name, self::$hooks)) {
 143                         foreach (self::$hooks[$name] as $hook) {
 144                                 // Call a hook to check if this hook call needs to be forked
 145                                 if (array_key_exists('hook_fork', self::$hooks)) {
 146                                         $hookdata = ['name' => $name, 'data' => $data, 'execute' => true];
 147
 148                                         foreach (self::$hooks['hook_fork'] as $fork_hook) {
 149                                                 if ($hook[0] != $fork_hook[0]) {
 150                                                         continue;
 151                                                 }
 152                                                 self::callSingle(DI::app(), 'hook_fork', $fork_hook, $hookdata);
 153                                         }
 154
 155                                         if (!$hookdata['execute']) {
 156                                                 continue;
 157                                         }
 158                                 }
 159
 160                                 Worker::add($priority, 'ForkHook', $name, $hook, $data);
 161                         }
 162                 }
 163         }
 164
 165         /**
 166          * @brief Calls a hook.
 167          *
 168          * Use this function when you want to be able to allow a hook to manipulate
 169          * the provided data.
 170          *
 171          * @param string        $name of the hook to call
 172          * @param string|array &$data to transmit to the callback handler
 173          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 174          */
 175         public static function callAll($name, &$data = null)
 176         {
 177                 if (array_key_exists($name, self::$hooks)) {
 178                         foreach (self::$hooks[$name] as $hook) {
 179                                 self::callSingle(DI::app(), $name, $hook, $data);
 180                         }
 181                 }
 182         }
 183
 184         /**
 185          * @brief Calls a single hook.
 186          *
 187          * @param App             $a
 188          * @param string          $name of the hook to call
 189          * @param array           $hook Hook data
 190          * @param string|array   &$data to transmit to the callback handler
 191          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 192          */
 193         public static function callSingle(App $a, $name, $hook, &$data = null)
 194         {
 195                 // Don't run a theme's hook if the user isn't using the theme
 196                 if (strpos($hook[0], 'view/theme/') !== false && strpos($hook[0], 'view/theme/' . $a->getCurrentTheme()) === false) {
 197                         return;
 198                 }
 199
 200                 @include_once($hook[0]);
 201                 if (function_exists($hook[1])) {
 202                         $func = $hook[1];
 203                         $func($a, $data);
 204                 } else {
 205                         // remove orphan hooks
 206                         $condition = ['hook' => $name, 'file' => $hook[0], 'function' => $hook[1]];
 207                         DBA::delete('hook', $condition, ['cascade' => false]);
 208                 }
 209         }
 210
 211         /**
 212          * Checks if an app_menu hook exist for the provided addon name.
 213          * Return true if the addon is an app
 214          *
 215          * @param string $name Name of the addon
 216          * @return boolean
 217          */
 218         public static function isAddonApp($name)
 219         {
 220                 $name = Strings::sanitizeFilePathItem($name);
 221
 222                 if (array_key_exists('app_menu', self::$hooks)) {
 223                         foreach (self::$hooks['app_menu'] as $hook) {
 224                                 if ($hook[0] == 'addon/' . $name . '/' . $name . '.php') {
 225                                         return true;
 226                                 }
 227                         }
 228                 }
 229
 230                 return false;
 231         }
 232 }