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class SnowballStemmer in Snowball Stemmer 8

Same name and namespace in other branches
  1. 2.x src/Plugin/search_api/processor/SnowballStemmer.php \Drupal\snowball_stemmer\Plugin\search_api\processor\SnowballStemmer

Stems search terms.

Plugin annotation


@SearchApiProcessor(
  id = "snowball_stemmer",
  label = @Translation("Snowball stemmer"),
  description = @Translation("Stems search terms, using <a href=""https://github.com/wamania/php-stemmer"">PHP snowball stemmer</a>, which supports multiple languages. For best results, use after tokenizing."),
  stages = {
    "pre_index_save" = 0,
    "preprocess_index" = 0,
    "preprocess_query" = 0,
  }
)

Hierarchy

Expanded class hierarchy of SnowballStemmer

1 file declares its use of SnowballStemmer
StemmerTest.php in tests/src/Unit/Plugin/Processor/StemmerTest.php

File

src/Plugin/search_api/processor/SnowballStemmer.php, line 25

Namespace

Drupal\snowball_stemmer\Plugin\search_api\processor
View source 
class SnowballStemmer extends StemmerProcessor {

  /**
   * The stemmer service.
   *
   * @var \Drupal\snowball_stemmer\Stemmer|null
   */
  protected $stemmer;

  /**
   * The language manager.
   *
   * @var \Drupal\Core\Language\LanguageManagerInterface
   */
  protected $languageManager;

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {

    /** @var static $processor */
    $processor = parent::create($container, $configuration, $plugin_id, $plugin_definition);
    $processor
      ->setStemmer($container
      ->get('snowball_stemmer.stemmer'));
    $processor
      ->setLanguageManager($container
      ->get('language_manager'));
    return $processor;
  }

  /**
   * Retrieves the stemmer service.
   *
   * @return \Drupal\snowball_stemmer\Stemmer
   *   The stemmer service.
   */
  public function getStemmer() {
    $stemmer = $this->stemmer ?: \Drupal::service('snowball_stemmer.stemmer');

    // @todo allow multilingual overrides.
    $stemmer
      ->setOverrides($this->configuration['exceptions']);
    return $stemmer;
  }

  /**
   * Sets the stemmer service.
   *
   * @param \Drupal\snowball_stemmer\Stemmer $stemmer
   *   The stemmer service.
   *
   * @return $this
   */
  public function setStemmer(Stemmer $stemmer) {
    $this->stemmer = $stemmer;
    return $this;
  }

  /**
   * Retrieves the language manager.
   *
   * @return \Drupal\Core\Language\LanguageInterface
   *   The language manager.
   */
  public function getLanguageManager() {
    return $this->languageManager ?: \Drupal::service('language_manager');
  }

  /**
   * Sets the language manager.
   *
   * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
   *   The language manager.
   *
   * @return $this
   */
  public function setLanguageManager(LanguageManagerInterface $language_manager) {
    $this->languageManager = $language_manager;
    return $this;
  }

  /**
   * {@inheritdoc}
   */
  public function preprocessIndexItems(array $items) {
    foreach ($items as $item) {
      if ($this
        ->getStemmer()
        ->setLanguage($item
        ->getLanguage())) {
        foreach ($item
          ->getFields() as $name => $field) {
          if ($this
            ->testField($name, $field)) {
            $this
              ->processField($field);
          }
        }
      }
    }
  }

  /**
   * {@inheritdoc}
   */
  public function preprocessSearchQuery(QueryInterface $query) {

    // Try the queries language, and if not fallback to the current site
    // language.
    if ($languages = $query
      ->getLanguages()) {

      // Todo: What if there is more than one language?
      $language = reset($languages);
    }
    else {
      $language = $this
        ->getLanguageManager()
        ->getCurrentLanguage()
        ->getId();
    }
    $keys =& $query
      ->getKeys();
    if (isset($keys) && $this
      ->getStemmer()
      ->setLanguage($language)) {
      $this
        ->processKeys($keys);
    }
    $conditions = $query
      ->getConditionGroup();
    $this
      ->processConditions($conditions
      ->getConditions());
  }

  /**
   * {@inheritdoc}
   */
  protected function process(&$value) {

    // In the absence of the tokenizer, and/or HTML processor, this ensures
    // split words for stemming. Leaves strings in much the same state as
    // search api will for storage.
    $words = preg_split('/[^\\p{L}\\p{N}]+/u', strip_tags($value), -1, PREG_SPLIT_NO_EMPTY);
    $stemmed = [];
    foreach ($words as $word) {
      $stemmed[] = $this
        ->stem($word);
    }
    $value = implode(' ', $stemmed);
  }

  /**
   * Actually stem word, if required.
   */
  protected function stem($word) {
    if (strlen($word)) {
      $word = $this
        ->getStemmer()
        ->stem($word);
    }
    return $word;
  }

}

Members

Namesort descending Modifiers Type Description Overrides
ConfigurablePluginBase::calculateDependencies public function Calculates dependencies for the configured plugin. Overrides DependentPluginInterface::calculateDependencies 6
ConfigurablePluginBase::calculatePluginDependencies Deprecated protected function Calculates and adds dependencies of a specific plugin instance.
ConfigurablePluginBase::getConfiguration public function Gets this plugin's configuration. Overrides ConfigurableInterface::getConfiguration
ConfigurablePluginBase::getDescription public function Returns the plugin's description. Overrides ConfigurablePluginInterface::getDescription
ConfigurablePluginBase::getPluginDependencies Deprecated protected function Calculates and returns dependencies of a specific plugin instance.
ConfigurablePluginBase::label public function Returns the label for use on the administration pages. Overrides ConfigurablePluginInterface::label
ConfigurablePluginBase::moduleHandler Deprecated protected function Wraps the module handler.
ConfigurablePluginBase::onDependencyRemoval public function Informs the plugin that some of its dependencies are being removed. Overrides ConfigurablePluginInterface::onDependencyRemoval 5
ConfigurablePluginBase::setConfiguration public function Sets the configuration for this plugin instance. Overrides ConfigurableInterface::setConfiguration 3
ConfigurablePluginBase::themeHandler Deprecated protected function Wraps the theme handler.
DependencySerializationTrait::$_entityStorages protected property An array of entity type IDs keyed by the property name of their storages.
DependencySerializationTrait::$_serviceIds protected property An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::__sleep public function 1
DependencySerializationTrait::__wakeup public function 2
DependencyTrait::$dependencies protected property The object's dependencies.
DependencyTrait::addDependencies protected function Adds multiple dependencies.
DependencyTrait::addDependency protected function Adds a dependency.
FieldsProcessorPluginBase::$dataTypeHelper protected property The data type helper. 1
FieldsProcessorPluginBase::$elementInfoManager protected property The element info manager.
FieldsProcessorPluginBase::getDataTypeHelper public function Retrieves the data type helper. 1
FieldsProcessorPluginBase::getElementInfoManager public function Retrieves the element info manager.
FieldsProcessorPluginBase::preIndexSave public function Preprocesses the search index entity before it is saved. Overrides ProcessorPluginBase::preIndexSave
FieldsProcessorPluginBase::preRenderFieldsCheckboxes public static function Preprocesses the "fields" checkboxes before rendering.
FieldsProcessorPluginBase::processConditions protected function Preprocesses the query conditions.
FieldsProcessorPluginBase::processConditionValue protected function Processes a single condition value. 1
FieldsProcessorPluginBase::processField protected function Processes a single field's value. 3
FieldsProcessorPluginBase::processFieldValue protected function Processes a single text element in a field. 3
FieldsProcessorPluginBase::processKey protected function Processes a single search keyword. 1
FieldsProcessorPluginBase::processKeys protected function Preprocesses the search keywords.
FieldsProcessorPluginBase::setDataTypeHelper public function Sets the data type helper. 1
FieldsProcessorPluginBase::setElementInfoManager public function Sets the element info manager.
FieldsProcessorPluginBase::shouldProcess protected function Determines whether a single value (not an array) should be processed. 1
FieldsProcessorPluginBase::testField protected function Tests whether a certain field should be processed. 1
FieldsProcessorPluginBase::trustedCallbacks public static function Lists the trusted callbacks provided by the implementing class. Overrides TrustedCallbackInterface::trustedCallbacks
IndexPluginBase::$index protected property The index this processor is configured for.
IndexPluginBase::getIndex public function Retrieves the index this plugin is configured for. Overrides IndexPluginInterface::getIndex
IndexPluginBase::setIndex public function Sets the index this plugin is configured for. Overrides IndexPluginInterface::setIndex
IndexPluginBase::__construct public function Constructs a \Drupal\Component\Plugin\PluginBase object. Overrides ConfigurablePluginBase::__construct 2
MessengerTrait::$messenger protected property The messenger. 29
MessengerTrait::messenger public function Gets the messenger. 29
MessengerTrait::setMessenger public function Sets the messenger.
PluginBase::$configuration protected property Configuration information passed into the plugin. 1
PluginBase::$pluginDefinition protected property The plugin implementation definition. 1
PluginBase::$pluginId protected property The plugin_id.
PluginBase::DERIVATIVE_SEPARATOR constant A string which is used to separate base plugin IDs from the derivative ID.
PluginBase::getBaseId public function Gets the base_plugin_id of the plugin instance. Overrides DerivativeInspectionInterface::getBaseId
PluginBase::getDerivativeId public function Gets the derivative_id of the plugin instance. Overrides DerivativeInspectionInterface::getDerivativeId
PluginBase::getPluginDefinition public function Gets the definition of the plugin implementation. Overrides PluginInspectionInterface::getPluginDefinition 3
PluginBase::getPluginId public function Gets the plugin_id of the plugin instance. Overrides PluginInspectionInterface::getPluginId
PluginBase::isConfigurable public function Determines if the plugin is configurable.
PluginDependencyTrait::calculatePluginDependencies protected function Calculates and adds dependencies of a specific plugin instance. Aliased as: traitCalculatePluginDependencies 1
PluginDependencyTrait::getPluginDependencies protected function Calculates and returns dependencies of a specific plugin instance. Aliased as: traitGetPluginDependencies
PluginDependencyTrait::moduleHandler protected function Wraps the module handler. Aliased as: traitModuleHandler 1
PluginDependencyTrait::themeHandler protected function Wraps the theme handler. Aliased as: traitThemeHandler 1
PluginFormTrait::submitConfigurationForm public function Form submission handler. 7
ProcessorInterface::STAGE_ADD_PROPERTIES constant Processing stage: add properties.
ProcessorInterface::STAGE_ALTER_ITEMS constant Processing stage: alter indexed items.
ProcessorInterface::STAGE_POSTPROCESS_QUERY constant Processing stage: postprocess query.
ProcessorInterface::STAGE_PREPROCESS_INDEX constant Processing stage: preprocess index.
ProcessorInterface::STAGE_PREPROCESS_QUERY constant Processing stage: preprocess query.
ProcessorInterface::STAGE_PRE_INDEX_SAVE constant Processing stage: preprocess index.
ProcessorPluginBase::$fieldsHelper protected property The fields helper. 1
ProcessorPluginBase::addFieldValues public function Adds the values of properties defined by this processor to the item. Overrides ProcessorInterface::addFieldValues 8
ProcessorPluginBase::alterIndexedItems public function Alter the items to be indexed. Overrides ProcessorInterface::alterIndexedItems 3
ProcessorPluginBase::ensureField protected function Ensures that a field with certain properties is indexed on the index.
ProcessorPluginBase::findField protected function Finds a certain field in the index.
ProcessorPluginBase::getFieldsHelper public function Retrieves the fields helper. 1
ProcessorPluginBase::getPropertyDefinitions public function Retrieves the properties this processor defines for the given datasource. Overrides ProcessorInterface::getPropertyDefinitions 8
ProcessorPluginBase::getWeight public function Returns the weight for a specific processing stage. Overrides ProcessorInterface::getWeight
ProcessorPluginBase::isHidden public function Determines whether this plugin should be hidden in the UI. Overrides HideablePluginBase::isHidden
ProcessorPluginBase::isLocked public function Determines whether this processor should always be enabled. Overrides ProcessorInterface::isLocked
ProcessorPluginBase::postprocessSearchResults public function Postprocess search results before they are returned by the query. Overrides ProcessorInterface::postprocessSearchResults 2
ProcessorPluginBase::requiresReindexing public function Determines whether re-indexing is required after a settings change. Overrides ProcessorInterface::requiresReindexing
ProcessorPluginBase::setFieldsHelper public function Sets the fields helper. 1
ProcessorPluginBase::setWeight public function Sets the weight for a specific processing stage. Overrides ProcessorInterface::setWeight
ProcessorPluginBase::supportsStage public function Checks whether this processor implements a particular stage. Overrides ProcessorInterface::supportsStage 2
SnowballStemmer::$languageManager protected property The language manager.
SnowballStemmer::$stemmer protected property The stemmer service.
SnowballStemmer::create public static function Creates an instance of the plugin. Overrides FieldsProcessorPluginBase::create
SnowballStemmer::getLanguageManager public function Retrieves the language manager.
SnowballStemmer::getStemmer public function Retrieves the stemmer service.
SnowballStemmer::preprocessIndexItems public function Preprocesses search items for indexing. Overrides Stemmer::preprocessIndexItems
SnowballStemmer::preprocessSearchQuery public function Preprocesses a search query. Overrides Stemmer::preprocessSearchQuery
SnowballStemmer::process protected function Processes a single string value. Overrides Stemmer::process
SnowballStemmer::setLanguageManager public function Sets the language manager.
SnowballStemmer::setStemmer public function Sets the stemmer service.
SnowballStemmer::stem protected function Actually stem word, if required.
Stemmer::$stems protected property Static cache for already-generated stems.
Stemmer::buildConfigurationForm public function Form constructor. Overrides FieldsProcessorPluginBase::buildConfigurationForm
Stemmer::defaultConfiguration public function Gets default configuration for this plugin. Overrides FieldsProcessorPluginBase::defaultConfiguration
Stemmer::supportsIndex public static function Checks whether this processor is applicable for a certain index. Overrides ProcessorPluginBase::supportsIndex
Stemmer::testType protected function Determines whether a field of a certain type should be preprocessed. Overrides FieldsProcessorPluginBase::testType
Stemmer::validateConfigurationForm public function Form validation handler. Overrides FieldsProcessorPluginBase::validateConfigurationForm
StringTranslationTrait::$stringTranslation protected property The string translation service. 1
StringTranslationTrait::formatPlural protected function Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals protected function Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation protected function Gets the string translation service.
StringTranslationTrait::setStringTranslation public function Sets the string translation service to use. 2
StringTranslationTrait::t protected function Translates a string to the current language or to a given language.
TrustedCallbackInterface::THROW_EXCEPTION constant Untrusted callbacks throw exceptions.
TrustedCallbackInterface::TRIGGER_SILENCED_DEPRECATION constant Untrusted callbacks trigger silenced E_USER_DEPRECATION errors.
TrustedCallbackInterface::TRIGGER_WARNING constant Untrusted callbacks trigger E_USER_WARNING errors.