public function delete()
 {
     // if file was uploaded now (so already existing won't be affected)
     if ($this->uploadedFile && $this->fileInfo) {
         $this->fileInfo->delete();
     }
 }
 public function getFileInfo()
 {
     return $this->hasOne(FileInfo::className(), ['id' => 'files_info_id']);
 }
 public function getFileInfos()
 {
     return $this->hasMany(FileInfo::className(), ['id' => 'files_info_id'])->viaTable('post_data_files_info', ['post_data_id' => 'id']);
 }
 public function actionExists($hash)
 {
     return FileInfo::find()->where(['hash' => $hash])->exists();
 }