hasNonInternalResourceType example

  public static function getRelationshipLinks(ResourceObject $relationship_context, ResourceTypeRelationship $resource_relationship) {
    $resource_type = $relationship_context->getResourceType();
    if ($resource_type->isInternal() || !$resource_type->isLocatable()) {
      return [];
    }
    $public_field_name = $resource_relationship->getPublicName();
    $relationship_route_name = Routes::getRouteName($resource_type, "$public_field_name.relationship.get");
    $links = [
      'self' => Url::fromRoute($relationship_route_name, ['entity' => $relationship_context->getId()]),
    ];
    if (static::hasNonInternalResourceType($resource_type->getRelatableResourceTypesByField($public_field_name))) {
      $related_route_name = Routes::getRouteName($resource_type, "$public_field_name.related");
      $links['related'] = Url::fromRoute($related_route_name, ['entity' => $relationship_context->getId()]);
    }
    if ($resource_type->isVersionable()) {
      $version_query_parameter = [JsonApiSpec::VERSION_QUERY_PARAMETER => $relationship_context->getVersionIdentifier()];
      $links['self']->setOption('query', $version_query_parameter);
      if (isset($links['related'])) {
        $links['related']->setOption('query', $version_query_parameter);
      }
    }
    return $links;
  }