ElggPlugin::getStaticConfig PHP Method

    public function getStaticConfig($key, $default = null)
    {
        if ($this->static_config === null) {
            $this->static_config = [];
            if ($this->canReadFile(ElggPluginPackage::STATIC_CONFIG_FILENAME)) {
                $this->static_config = $this->includeFile(ElggPluginPackage::STATIC_CONFIG_FILENAME);
            }
        }
        if (array_key_exists($key, $this->static_config)) {
            return $this->static_config[$key];
        } else {
            return $default;
        }
    }

 /**
  * Creates new ElggUpgrade instance from plugin's static config
  *
  * @param \ElggPlugin $plugin Plugin
  * @return \ElggUpgrade[]
  */
 public function getUpgrades(\ElggPlugin $plugin)
 {
     $upgrades = [];
     $batches = $plugin->getStaticConfig('upgrades');
     if (empty($batches)) {
         // No upgrades available for this plugin
         return $upgrades;
     }
     $plugin_id = $plugin->getID();
     foreach ($batches as $class) {
         $batch = $this->getBatch($class);
         if (!$batch) {
             continue;
         }
         $version = $batch::VERSION;
         $upgrade_id = "{$plugin_id}:{$version}";
         // Database holds the information of which upgrades have been processed
         if ($this->upgradeExists($upgrade_id)) {
             $this->logger->info("Upgrade {$upgrade_id} has already been processed");
             continue;
         }
         // Create a new ElggUpgrade to represent the upgrade in the database
         $object = new ElggUpgrade();
         $object->setId($upgrade_id);
         $object->setClass($class);
         $object->title = "{$plugin_id}:upgrade:{$version}:title";
         $object->description = "{$plugin_id}:upgrade:{$version}:description";
         $object->offset = 0;
         try {
             $object->save();
             $upgrades[] = $object;
         } catch (\UnexpectedValueException $ex) {
             $this->logger->error($ex->getMessage());
         }
     }
     return $upgrades;
 }