Elasticsearch - Search API
About
This module provides a way to easily created faceted search pages. Depends on search_api and elasticsearch_connector to index content.
Features:
- Ajax powered faceted search
- Synonyms
- Autocompletion
- Search suggestions
Installation
Add both this module and the block ui library to your project's composer.json, which is a dependency of this module:
"repositories": [
{
"type": "package",
"package": {
"name": "library-blockui/blockui",
"version": "v2.70",
"type": "drupal-library",
"dist": {
"url": "https://github.com/malsup/blockui/archive/2.70.zip",
"type": "zip"
}
}
}
]And install it as usual: composer require drupal/elasticsearch_search_api
Usage
Routes & Controllers
A search results page typically needs two routes/callbacks:
- search callback to render the search page on page loads
- filter callback to update the page using ajax
See elasticsearch_search_api.routing.yml.example for more info
For "default" search pages the src/Controller/SearchController.php can be extended and will provide most features. This can keep custom controllers relatively simple:
class MyCustomController extends SearchController {
public function __construct(RendererInterface $renderer, CurrentRouteMatch $routeMatch, SearchActionFactory $searchActionFactory, ElasticSearchParamsBuilder $searchParamsBuilder, ElasticSearchResultParser $resultParser, SuggesterInterface $suggester, SearchRepository $searchRepository, EntityTypeManagerInterface $entityTypeManager, RequestStack $requestStack) {
parent::__construct($renderer, $routeMatch, $searchActionFactory, $searchParamsBuilder, $resultParser, $suggester, $searchRepository, $entityTypeManager);
$this->facets = ['my-custom-facet'];
}
public static function create(ContainerInterface $container) {
return new static($container->get('renderer'), $container->get('current_route_match'), $container->get('elasticsearch_search_api.search_action_factory'), $container->get('elasticsearch_search_api.elasticsearch_params_builder'), $container->get('elasticsearch_search_api.elasticsearch_result_parser'), $container->get('elasticsearch_search_api.suggest.title_suggester'), $container->get('elasticsearch_search_api.search_repository'), $container->get('entity_type.manager'), $container->get('request_stack'));
}
protected function renderPager(ParameterBag $query, int $total, int $size) {
return [
'#theme' => 'elasticsearch_search_api_pager',
'#tags' => [
1 => 'Previous',
3 => 'Next',
],
'#element' => 0,
'#parameters' => $query->all(),
'#total_items' => $total,
'#items_per_page' => $size,
'#route_name' => $this->getSearchRouteName(),
];
}
protected function getFilterLink() {
return Url::fromRoute('my_module.my_filter_route')->toString();
}
protected function getSuggestions(ParameterBag $query) {
return [];
}
protected function getSearchHeader() {
return [
'#type' => 'container',
'#children' => $this->formBuilder()->getForm(SearchForm::class),
];
}
protected function getSearchRouteName() {
return 'my_module.my_search_route';
}
protected function getFilterRouteName() {
return 'my_module.my_filter_route';
}
}Facets
Creating and using facets requires the following:
- an instance of
Drupal\elasticsearch_search_api\Search\Facet\Control\CompositeFacetControlInterfaceorDrupal\elasticsearch_search_api\Search\Facet\Control\FacetControlInterface - a service tagged in the following format
elasticsearch_search_api.facet_control.my_facet - adding the facet to the constructor of the controller (see above)
Example of term-based facet:
class RegionFacetControl extends TermFacetBase {
use StringTranslationTrait;
const VOCABULARY_ID = 'MY_VOCABULARY';
const PROPERTY_PATH = 'SEARCH_API_PROPERTY_PATH';
public function __construct(FacetValueMetaDataTreeStorageInterface $facetValueMetaDataTreeStorage, string $routeName, EntityTypeManagerInterface $entityTypeManager) {
parent::__construct($facetValueMetaDataTreeStorage, $routeName, $entityTypeManager);
$this->setVocabulary(self::VOCABULARY_ID);
$this->setfacetValuesSortMethod(self::SORT_TERM_WEIGHT);
$this->setCanSelectMultiple(FALSE);
}
public function getFieldName(): string {
return self::PROPERTY_PATH;
}
public function addToAggregations(): bool {
return TRUE;
}
protected function getFacetTitle() {
return sprintf('<h2>%s</h2>', $this->t('MY_FACET_TITLE'));
}