How to create a view filter which display nodes if "field1" - "field2" < $amount

Baud

11/29/22, 8:43 PM

I have a content type with 2 fields: field1 and field2

I would like to create a view filter which display node based on a calculation on those two fields.

The filter should display only nodes if field1 - field2 is lower then a given amount.

Here is my try: At the end of the code, I don't know how to create the query

 class Myfilter extends FilterPluginBase implements ContainerFactoryPluginInterface {

  protected ViewsHandlerManager $joinHandler;

  private int $amount;

  public function __construct(array $configuration, $plugin_id, $plugin_definition, RouteMatchInterface $route_match, ViewsHandlerManager $join_handler) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->joinHandler = $join_handler;
    $this->amount = 0;
    if (($node = $route_match->getParameter('node')) && ($node->bundle()=='my_bundle')) {
      $this->amount = $node->get('field_inv_amount')->value;
    }

  }

  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static(
      $configuration, $plugin_id, $plugin_definition,
      $container->get('current_route_match'),
      $container->get('plugin.manager.views.join')
    );
  }

  public function query() {
    //parent::query();
    
    $fields = [
      'field1',
      'field2',
    ];
    foreach ($fields as $field) {
      $table_field_name = 'node__' . $field;
      $configuration = [
        'table' => $table_field_name,
        'field' => 'nid',
        'left_table' => 'node_field_data',
        'left_field' => 'nid',
        'operator' => '=',
      ];
      $join = $this->joinHandler->createInstance('standard', $configuration);
      $this->query->addRelationship($table_field_name, $join, 'node_field_data');
    }
    // I am stuck here... field1-field2 should be < $this->amount
    $this->query->addWhere( ???? );
  }

}

Any hint will be appreciated

1 + 2

views

beltouche

11/30/22, 3:11 AM

As an alternative, you might consider leveraging https://www.drupal.org/project/computed_field, and filter on the computed field.

Baud

11/30/22, 10:23 AM

@beltouche thank you. I can also populate a normal field during node_presave, but as I have many cases like this one, I would prefer to understand how to create those kind of query. (I regular sql, it is easy, so I assume it can be done with the $query object)

Score:1

Drupal

No Sssweat

12/1/22, 8:30 AM

You have a few errors:

The 'field' => 'nid', should be 'field' => 'entity_id',

~~The $join = line needs to use Drupal\views\Views::pluginManager('join')~~

You can using addWhereExpression, working example:

  public function query() {

    $fields = [
      'field_num1',
      'field_num2',
    ];

    foreach ($fields as $field) {
      $table_field_name = 'node__' . $field;
      $configuration = [
        'table' => $table_field_name,
        'field' => 'entity_id',
        'left_table' => 'node_field_data',
        'left_field' => 'nid',
        'operator' => '=',
      ];
      $join = $this->joinHandler->createInstance('standard', $configuration);
      $this->query->addRelationship($table_field_name, $join, 'node_field_data');
    }

    // Substracts and filters to less than amount.
    $this->query->addWhereExpression('AND', 'node__field_num1.field_num1_value - node__field_num2.field_num2_value <' . $this->amount);

  }

0 + 2

Baud

12/1/22, 12:24 PM

Many thanks!, it works like a charm! A small note: `$this->joinHandler` doesn't need to be replaced by `Drupal\views\Views::pluginManager('join')` because I used DI : `$container->get('plugin.manager.views.join')` is doing the same job.

No Sssweat

12/1/22, 8:09 PM

Oh yes [Dependency Injection](https://www.drupal.org/docs/drupal-apis/services-and-dependency-injection/services-and-dependency-injection-in-drupal-8#s-injecting-dependencies-into-controllers-forms-and-blocks), somehow I overlooked that.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: How to create a view filter which display nodes if "field1" - "field2" < $amount

TH: How to create a view filter which display nodes if "field1" - "field2"

RO: How to create a view filter which display nodes if "field1" - "field2"

RU: How to create a view filter which display nodes if "field1" - "field2"

VI: How to create a view filter which display nodes if "field1" - "field2"

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