/**
  * @return AttachmentInput
  */
 private function attachmentInputs()
 {
     $attachmentInput = new AttachmentInput();
     $attachmentInput->setFilename(self::DUMMY_FILENAME);
     $attachmentInput->setContent(self::DUMMY_FILE_CONTENT);
     return array($attachmentInput);
 }
 /**
  * @param Attachment[]|null $attachments
  * @return AttachmentInput[]|null
  */
 private function convertAttachments(array $attachments = null)
 {
     if (is_null($attachments)) {
         return null;
     }
     $result = null;
     foreach ($attachments as $attachment) {
         if ($attachment instanceof Attachment) {
             $input = new AttachmentInput();
             $input->setFilename($attachment->getName());
             $input->setContent($attachment->getContent());
             $result[] = $input;
         }
     }
     return $result;
 }