Doctrine\ODM\MongoDB\Mapping\MappingException::cannotLookupNonIdReference PHP Метод

    public static function cannotLookupNonIdReference($className, $fieldName)
    {
        return new self("Cannot use reference '{$fieldName}' in class '{$className}' for lookup. Only ID references are allowed in \$lookup stages.");
    }

 /**
  * @param string $fieldName
  * @return $this
  * @throws MappingException
  */
 private function fromReference($fieldName)
 {
     if (!$this->class->hasReference($fieldName)) {
         MappingException::referenceMappingNotFound($this->class->name, $fieldName);
     }
     $referenceMapping = $this->class->getFieldMapping($fieldName);
     $targetMapping = $this->dm->getClassMetadata($referenceMapping['targetDocument']);
     parent::from($targetMapping->getCollection());
     if ($referenceMapping['isOwningSide']) {
         if ($referenceMapping['storeAs'] !== ClassMetadataInfo::REFERENCE_STORE_AS_ID) {
             throw MappingException::cannotLookupNonIdReference($this->class->name, $fieldName);
         }
         $this->foreignField('_id')->localField($referenceMapping['name']);
     } else {
         if (isset($referenceMapping['repositoryMethod'])) {
             throw MappingException::repositoryMethodLookupNotAllowed($this->class->name, $fieldName);
         }
         $mappedByMapping = $targetMapping->getFieldMapping($referenceMapping['mappedBy']);
         if ($mappedByMapping['storeAs'] !== ClassMetadataInfo::REFERENCE_STORE_AS_ID) {
             throw MappingException::cannotLookupNonIdReference($this->class->name, $fieldName);
         }
         $this->localField('_id')->foreignField($mappedByMapping['name']);
     }
     return $this;
 }