How to exclude items from search api solr by negative keywords field

Question

Drupal 8, Search API SOLR.

I'd like to not return nodes if there are any matches between a field of negative keywords (on the node) and the query string the user has entered.

Module search_api_solr currently set up with several fields, matching in node titles, body and keyword fields.

e.g. node titled "I can't find my elephant" with a negative keyword field containing "wallet" to not show up in a search "I can't find my wallet".

Answer 1

You don't need to do this in solr, you can do it in the query or with views filters.

Something like this:

$solrIndex = \Drupal::entityTypeManager()->getStorage('search_api_index')->load('global');
$query = $solrIndex->query();
$query->addCondition('title', $search_string);

$search_terms = explode(' ', $search_string);

// Don't match items where elements in the title match the stop words
// for an entity.
foreach ($search_terms as $term) {
  $query->addCondition('field_stop_words', $term, '<>');
}

Answer 2

Please check the following screenshots.

Answer 3

This is the solution I came to:

Add the field in search API

Add a filter query in hook_search_api_solr_query_alter to exclude nodes with the negative keywords.

    // Generate a filter query to do a negative search for each word in the search string.
    $search_words = explode(' ', trim($query_string));
    $filter_query_parts = [];
    for ($x = 1; $x <= count($search_words); $x++) {
        $filter_query_parts[] = '-ts_field_negative_keywords:%' . $x . '%';
    }

    $filter_query_text = '( ' . implode(" OR ", $filter_query_parts) . ')';

    // Apply the filter query to the search.
    $solrQuery->createFilterQuery('ts_field_negative_keywords')->setQuery($filter_query_text, $search_words);