Fulltext Search Boosting

The Fulltext Search Boost functionality allows fine-tuning of search results by applying configurable boost values to specific content types, raw fields, and meta-fields. It comes in three parts:

Boosting configuration

Boosting configuration is applied during querying the search backend
Meta fields indexing configuration

Indexing configuration defines indexing for meta fields that are used in boosting
Netgen\IbexaSearchExtra\API\Values\Content\Query\Criterion\FullText criterion

A custom criterion implementation that that can define boosting rules per ContentType, raw search engine fields and meta fields.

The criterion is currently implemented for Solr search engine only.

Note

Boosting through the custom FullText criterion utilizes exists Solr function, from which it achieves linear increase of search hit score by the given factor. In contrast to alternative implementations, that makes it controllable even when using multiple boost rules.

Boosting configuration

The boosting configuration is defined under the netgen_ibexa_search_extra.fulltext.boost key in your project’s configuration files. This structure allows you to define multiple named configurations for different use cases. Each configuration specifies boost values for content types, raw fields, and meta-fields.

The configuration is structured as follows:

netgen_ibexa_search_extra:
    fulltext:
        boost:
            <name>:
                content_types:
                    <content_type_identifier>: <boost_value>
                raw_fields:
                    <raw_field_name>: <boost_value>
                meta_fields:
                    <meta_field_name>: <boost_value>

<name>: A unique identifier for the configuration. You can define multiple configurations for different scenarios (e.g., default, custom, etc.).
content_types: Specifies boost values for specific content types. The key is the content type identifier, and the value is the boost factor.
raw_fields: Specifies boost values for raw Solr fields. The key is the field name, and the value is the boost factor.
meta_fields: Specifies boost values for meta-fields. The key is the meta-field name, and the value is the boost factor.

Below is an example configuration with a name default:

netgen_ibexa_search_extra:
    fulltext:
        boost:
            default:
                content_types:
                    article: 2.5
                    blog_post: 1.8
                raw_fields:
                    meta_content__name_t: 2.1
                meta_fields:
                    title: 3.14

Meta-fields indexing configuration

Meta-fields are mapped during indexing, from one or multiple Content Fields. The configuration is defined on the same level as boost. It allows indexing meta-fields from specific ContentType fields or globally, from all ContentTypes. There are two ways to define the indexed fields:

Per ContentType

Specify the mapping with ContentType identifiers and field names. For example:

netgen_ibexa_search_extra:
    fulltext:
        meta_fields:
            title:
                - 'article/title'
                - 'blog_post/title'

In this example the title meta-field is mapped from the title field of the article and blog_post ContentTypes.

For all ContentTypes

Specify just the field name. In this case, the field applies to all ContentTypes. For example:
```
netgen_ibexa_search_extra:
    fulltext:
          meta_fields:
              title:
                - 'title'
```
In this example the title meta-field indexes the title field from any ContentType.

This flexibility allows you to configure meta-fields either specifically for certain content types or globally across all content types.

Creating a Criterion

The ConfiguredFulltextCriterionFactory class is responsible for creating FullText criterion with the specified boost configuration. When creating a criterion, you can specify the name of the configuration to use. If no name is provided, the factory defaults to the default configuration.

To create a FullText criterion, call the create method with the search term and the name of the configuration to use. For example:

$searchText = trim($request->query->get('searchText', ''));
$criterion = $configuredFulltextCriterionFactory->create($searchText, 'default');

In this example:

$searchText is the user-provided search term.
default is the name of the boost configuration to apply.

If the specified configuration name does not exist, an exception will be thrown.

You can also instantiate FullText criterion manually and set the boosting rules how you see fit:

use Netgen\IbexaSearchExtra\API\Values\Content\Query\Criterion\FullText;

$criterion = new FullText();

$criterion->contentTypeBoost = [
    'article' => 2,
];