*/
class HousingViewsData extends EntityViewsData {

  /**
   * {@inheritdoc}
   */
  public function getViewsData() {
    $data = parent::getViewsData();

    // Additional information for Views integration, such as table joins, can be
    // put here.

    // subscription__housings
    $data['housing']['subscription'] = [
      'title' => $this->t('Subscription reverse'),
      'help' => $this->t('Subscription to a Housing.'),
      'relationship' => [
        'field table' => 'subscription__housings',
        'field field' => 'housings_target_id',
        'field_name' => 'subscription_base',
        'id' => 'entity_reverse',
        'base' => 'subscription',
        'base field' => 'id',
        'label' => $this->t('Subscription reverse'),
      ],
    ];

/*
    $data['{MAIN ENTITY BASE TABLE}']['{useful non-conflicting name - I used the {RELATED ENTITY BASE TABLE}}'] = [
      'title' => t('{some useful title that displays in Add Relationships popup}'),
      'help' => t('{some useful description that displays in Add Relationships popup}'),
      'relationship' => [
        'field table' => '{name of intermediary table - it is probably {RELATED ENTITY}__{FIELD NAME}',
        'field field' => '{name of intermediary field - it is probably {FIELD NAME}_target_id',
        'base' => '{RELATED ENTITY BASE TABLE}',
        'base field' => '{RELATED ENTITY ID FIELD}',
        'id' => 'entity_reverse',
        'label' => '{some useful label that displays in Relationship select in various views field settings popups}',
      ],
    ];
*/