/**
* Retrieve Resource file handle (socket, file pointer etc)
*
* @return \Magento\Framework\Filesystem\File\ReadInterface
* @throws CoreException|\Exception
*/
protected function _getHandle()
{
if (!$this->_resourceFile) {
throw new CoreException(__('Please set resource file and link type.'));
}
if (is_null($this->_handle)) {
if ($this->_linkType == self::LINK_TYPE_URL) {
$this->_handle = $this->_filesystem->getRemoteResource($this->_resourceFile);
} elseif ($this->_linkType == self::LINK_TYPE_FILE) {
$this->_workingDirectory = $this->_filesystem->getDirectoryRead(Filesystem::MEDIA_DIR);
$fileExists = $this->_downloadableFile->ensureFileInFilesystem($this->_resourceFile);
if ($fileExists) {
$this->_handle = $this->_workingDirectory->openFile($this->_resourceFile);
} else {
throw new CoreException(__('Invalid download link type.'));
}
} else {
throw new CoreException(__('Invalid download link type.'));
}
}
return $this->_handle;
}
