DiskUploaderController::canUpload

public function canUpload(UploadRequest $uploadRequest = null): bool
{
	[$folder, $storage] = $this->getFolderAndStorage($uploadRequest ? $uploadRequest->getName() : '');

	if ($folder === null || $storage === null)
	{
		return false;
	}

	return $folder->canAdd($storage->getCurrentUserSecurityContext());
}