Issue #3271337 by acbramley, larowlan: Add native support for n-gram and edge n-gram

search_api_opensearch.services.yml

@@ -4,6 +4,10 @@ services:
     class: Drupal\search_api_opensearch\Connector\ConnectorPluginManager
     parent: default_plugin_manager
 
+  plugin.manager.search_api_opensearch.analyser:
+    class: Drupal\search_api_opensearch\Analyser\AnalyserManager
+    parent: default_plugin_manager
+
   logger.channel.search_api_opensearch:
     parent: logger.channel_base
     arguments: [ 'search_api_opensearch' ]
@@ -54,3 +58,4 @@ services:
       - '@search_api.fields_helper'
       - '@search_api_opensearch.field_mapper'
       - '@logger.channel.search_api_opensearch'
+      - '@plugin.manager.search_api_opensearch.analyser'

src/Analyser/AnalyserBase.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Analyser;
+
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\PluginBase;
+
+/**
+ * Defines a base class for analyser plugins.
+ */
+abstract class AnalyserBase extends PluginBase implements AnalyserInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getLabel(): string {
+    return $this->getPluginDefinition()['label'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSettings(): array {
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getConfiguration(): array {
+    return $this->configuration;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setConfiguration(array $configuration): self {
+    $this->configuration = $configuration;
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration(): array {
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state): array {
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateConfigurationForm(array &$form, FormStateInterface $form_state): void {
+    // Nil op.
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitConfigurationForm(array &$form, FormStateInterface $form_state): void {
+    // Nil op.
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPluginId(): string {
+    return $this->pluginId;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPluginDefinition(): array {
+    return $this->pluginDefinition;
+  }
+
+}
\ No newline at end of file

src/Analyser/AnalyserInterface.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Analyser;
+
+use Drupal\Component\Plugin\ConfigurableInterface;
+use Drupal\Component\Plugin\PluginInspectionInterface;
+use Drupal\Core\Plugin\PluginFormInterface;
+use OpenSearch\Client;
+
+/**
+ * Defines an interface for analyser plugins.
+ */
+interface AnalyserInterface extends PluginFormInterface, ConfigurableInterface, PluginInspectionInterface {
+
+  /**
+   * Gets the analyser label.
+   *
+   * @return string
+   *   The label.
+   */
+  public function getLabel(): string;
+
+  /**
+   * Gets the analyser settings.
+   *
+   * @return array
+   *   Analyser settings.
+   */
+  public function getSettings(): array;
+
+}
\ No newline at end of file

src/Analyser/AnalyserManager.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Analyser;
+
+use Drupal\Core\Cache\CacheBackendInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Plugin\DefaultPluginManager;
+use Drupal\search_api_opensearch\Annotation\OpenSearchAnalyser;
+
+/**
+ * Defines a plugin manager for analyser plugins.
+ */
+final class AnalyserManager extends DefaultPluginManager {
+
+  /**
+   * Constructs a AnalyserManager object.
+   *
+   * @param \Traversable $namespaces
+   *   An object that implements \Traversable which contains the root paths
+   *   keyed by the corresponding namespace to look for plugin implementations.
+   * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
+   *   Cache backend instance to use.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler to invoke the alter hook with.
+   */
+  public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {
+    $this->alterInfo('opensearch_analyser_info');
+    $this->setCacheBackend($cache_backend, 'opensearch_analyser_plugins');
+
+    parent::__construct('Plugin/OpenSearch/Analyser', $namespaces, $module_handler, AnalyserInterface::class, OpenSearchAnalyser::class);
+  }
+}
\ No newline at end of file

src/Annotation/OpenSearchAnalyser.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Annotation;
+
+use Drupal\Component\Annotation\Plugin;
+use Drupal\Core\Annotation\Translation;
+
+/**
+ * Defines an annotation for open search analyser plugins.
+ *
+ * @Annotation
+ */
+final class OpenSearchAnalyser extends Plugin {
+
+  /**
+   * Plugin ID.
+   */
+  public string $id;
+
+  /**
+   * Plugin label.
+   */
+  public string|Translation $label;
+
+}
\ No newline at end of file

src/Plugin/OpenSearch/Analyser/EdgeNgram.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Plugin\OpenSearch\Analyser;
+
+use Drupal\search_api_opensearch\Analyser\AnalyserBase;
+use Drupal\search_api_opensearch\Annotation\OpenSearchAnalyser;
+
+/**
+ * Defines an Edge N-gram analyser.
+ *
+ * @OpenSearchAnalyser(
+ *   id = \Drupal\search_api_opensearch\Plugin\OpenSearch\Analyser\EdgeNgram::PLUGIN_ID,
+ *   label = @Translation("Edge N-gram analyzer"),
+ * )
+ */
+final class EdgeNgram extends AnalyserBase {
+
+  /**
+   * The plugin ID.
+   */
+  public const PLUGIN_ID = 'edge_ngram_analyzer';
+
+  /**
+   * The filter ID.
+   */
+  public const FILTER_ID = 'edge_ngram_filter';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSettings(): array {
+    return [
+      'analysis' => [
+        'filter' => [
+          self::FILTER_ID => [
+            'type' => 'edge_ngram',
+            'min_gram' => 1,
+            'max_gram' => 20,
+          ],
+        ],
+        'analyzer' => [
+          self::PLUGIN_ID => [
+            'type' => 'custom',
+            'tokenizer' => 'standard',
+            'filter' => ['lowercase', 'asciifolding', self::FILTER_ID],
+          ],
+        ],
+      ],
+    ];
+  }
+
+}

src/Plugin/OpenSearch/Analyser/Ngram.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Plugin\OpenSearch\Analyser;
+
+use Drupal\search_api_opensearch\Analyser\AnalyserBase;
+use Drupal\search_api_opensearch\Annotation\OpenSearchAnalyser;
+
+/**
+ * Defines an N-gram analyser.
+ *
+ * @OpenSearchAnalyser(
+ *   id = \Drupal\search_api_opensearch\Plugin\OpenSearch\Analyser\Ngram::PLUGIN_ID,
+ *   label = @Translation("N-gram analyzer"),
+ * )
+ */
+final class Ngram extends AnalyserBase {
+
+  /**
+   * The plugin ID.
+   */
+  public const PLUGIN_ID = 'ngram_analyzer';
+
+  /**
+   * The filter ID.
+   */
+  public const FILTER_ID = 'ngram_filter';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSettings(): array {
+    return [
+      'analysis' => [
+        'filter' => [
+          self::FILTER_ID => [
+            'type' => 'ngram',
+            'min_gram' => 1,
+            'max_gram' => 20,
+          ],
+        ],
+        'analyzer' => [
+          self::PLUGIN_ID => [
+            'type' => 'custom',
+            'tokenizer' => 'standard',
+            'filter' => ['lowercase', 'asciifolding', self::FILTER_ID],
+          ],
+        ],
+      ],
+    ];
+  }
+
+}

src/Plugin/search_api/backend/OpenSearchBackend.php

@@ -445,4 +445,11 @@ class OpenSearchBackend extends BackendPluginBase implements PluginFormInterface
     return $vars;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function supportsDataType($type) {
+    return parent::supportsDataType($type) || str_starts_with($type, 'search_api_opensearch_');
+  }
+
 }

src/Plugin/search_api/data_type/EdgeNgramDataType.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Plugin\search_api\data_type;
+
+use Drupal\search_api\Plugin\search_api\data_type\TextDataType;
+
+/**
+ * Defines a class for n-gram data type.
+ *
+ * @SearchApiDataType(
+ *   id = "search_api_opensearch_edge_ngram",
+ *   label = @Translation("Edge N-gram"),
+ *   description = @Translation("Edge ngram"),
+ *   fallback_type = "text",
+ * )
+ */
+final class EdgeNgramDataType extends TextDataType {
+
+}

src/Plugin/search_api/data_type/NgramDataType.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\search_api_opensearch\Plugin\search_api\data_type;
+
+use Drupal\search_api\Plugin\search_api\data_type\TextDataType;
+
+/**
+ * Defines a class for n-gram data type.
+ *
+ * @SearchApiDataType(
+ *   id = "search_api_opensearch_ngram",
+ *   label = @Translation("N-gram"),
+ *   description = @Translation("ngram"),
+ *   fallback_type = "text",
+ * )
+ */
+final class NgramDataType extends TextDataType {
+
+}
\ No newline at end of file

src/SearchAPI/BackendClient.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\search_api_opensearch\SearchAPI;
 
+use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\DependencyInjection\DependencySerializationTrait;
 use Drupal\Core\Utility\Error;
 use Drupal\search_api\IndexInterface;
@@ -9,6 +10,8 @@ use Drupal\search_api\Query\QueryInterface;
 use Drupal\search_api\Query\ResultSetInterface;
 use Drupal\search_api\SearchApiException;
 use Drupal\search_api\Utility\FieldsHelperInterface;
+use Drupal\search_api_opensearch\Analyser\AnalyserInterface;
+use Drupal\search_api_opensearch\Analyser\AnalyserManager;
 use Drupal\search_api_opensearch\SearchAPI\Query\QueryParamBuilder;
 use Drupal\search_api_opensearch\SearchAPI\Query\QueryResultParser;
 use OpenSearch\Client;
@@ -72,6 +75,11 @@ class BackendClient implements BackendClientInterface {
    */
   protected $logger;
 
+  /**
+   * Client settings.
+   */
+  protected array $settings = [];
+
   /**
    * Constructs a new BackendClient.
    *
@@ -91,8 +99,10 @@ class BackendClient implements BackendClientInterface {
    *   The OpenSearch client.
    * @param array $settings
    *   The settings.
+   * @param \Drupal\search_api_opensearch\Analyser\AnalyserManager $analyserManager
+   *   Analyser manager.
    */
-  public function __construct(QueryParamBuilder $queryParamBuilder, QueryResultParser $resultParser, IndexParamBuilder $indexParamBuilder, FieldsHelperInterface $fieldsHelper, FieldMapper $fieldParamsBuilder, LoggerInterface $logger, Client $client, array $settings) {
+  public function __construct(QueryParamBuilder $queryParamBuilder, QueryResultParser $resultParser, IndexParamBuilder $indexParamBuilder, FieldsHelperInterface $fieldsHelper, FieldMapper $fieldParamsBuilder, LoggerInterface $logger, Client $client, array $settings, protected AnalyserManager $analyserManager) {
     $this->indexParamBuilder = $indexParamBuilder;
     $this->queryParamBuilder = $queryParamBuilder;
     $this->resultParser = $resultParser;
@@ -246,6 +256,7 @@ class BackendClient implements BackendClientInterface {
       $this->client->indices()->create([
         'index' => $indexId,
       ]);
+      $this->updateSettings($index);
       $this->updateFieldMapping($index);
     }
     catch (OpenSearchException $e) {
@@ -334,4 +345,46 @@ class BackendClient implements BackendClientInterface {
     return $vars;
   }
 
+  /**
+   * Updates index settings.
+   *
+   * @param \Drupal\search_api\IndexInterface $index_param
+   *   Index.
+   */
+  public function updateSettings(IndexInterface $index_param): void {
+    $indexId = $this->getIndexId($index_param);
+    $params = $this->fieldParamsBuilder->mapFieldParams($indexId, $index_param);
+    $analysers = array_reduce($params['body']['properties'], function (array $carry, array $field_definition) {
+      if (isset($field_definition['analyzer'])) {
+        $carry[$field_definition['analyzer']] = $field_definition['analyzer_settings'] ?? [];
+      }
+      return $carry;
+    }, []);
+    $settings = [];
+    foreach ($analysers as $analyser_id => $configuration) {
+      $analyser = $this->analyserManager->createInstance($analyser_id, $configuration);
+      assert($analyser instanceof AnalyserInterface);
+      $settings = NestedArray::mergeDeep($settings, $analyser->getSettings());
+    }
+    if (!$settings) {
+      // Nothing to push.
+      return;
+    }
+    try {
+      $index_param = [
+        'index' => $indexId,
+      ];
+      $this->client->indices()->close($index_param);
+      $this->client->indices()->putSettings($index_param + [
+        'body' => $settings,
+      ]);
+    }
+    catch (OpenSearchException $e) {
+      throw new SearchApiException(sprintf('An error occurred updating settings for index %s.', $indexId), 0, $e);
+    }
+    finally {
+      $this->client->indices()->open($index_param);
+    }
+  }
+
 }

src/SearchAPI/BackendClientFactory.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\search_api_opensearch\SearchAPI;
 
+use Drupal\search_api_opensearch\Analyser\AnalyserManager;
 use Drupal\search_api_opensearch\SearchAPI\Query\QueryParamBuilder;
 use Drupal\search_api_opensearch\SearchAPI\Query\QueryResultParser;
 use Drupal\search_api\Utility\FieldsHelperInterface;
@@ -73,8 +74,10 @@ class BackendClientFactory {
    *   The field mapper.
    * @param \Psr\Log\LoggerInterface $logger
    *   The logger.
+   * @param \Drupal\search_api_opensearch\Analyser\AnalyserManager $analyserManager
+   *   Analyser manager.
    */
-  public function __construct(QueryParamBuilder $queryParamBuilder, QueryResultParser $resultParser, IndexParamBuilder $itemParamBuilder, FieldsHelperInterface $fieldsHelper, FieldMapper $fieldParamsBuilder, LoggerInterface $logger) {
+  public function __construct(QueryParamBuilder $queryParamBuilder, QueryResultParser $resultParser, IndexParamBuilder $itemParamBuilder, FieldsHelperInterface $fieldsHelper, FieldMapper $fieldParamsBuilder, LoggerInterface $logger, protected AnalyserManager $analyserManager) {
     $this->itemParamBuilder = $itemParamBuilder;
     $this->queryParamBuilder = $queryParamBuilder;
     $this->resultParser = $resultParser;
@@ -104,6 +107,7 @@ class BackendClientFactory {
       $this->logger,
       $client,
       $settings,
+      $this->analyserManager,
     );
   }
 

src/SearchAPI/FieldMapper.php

@@ -6,6 +6,8 @@ use Drupal\search_api\IndexInterface;
 use Drupal\search_api\Item\FieldInterface;
 use Drupal\search_api\Utility\FieldsHelperInterface;
 use Drupal\search_api_opensearch\Event\FieldMappingEvent;
+use Drupal\search_api_opensearch\Plugin\OpenSearch\Analyser\EdgeNgram;
+use Drupal\search_api_opensearch\Plugin\OpenSearch\Analyser\Ngram;
 use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
@@ -136,6 +138,18 @@ class FieldMapper {
           ],
         ],
       ],
+      'search_api_opensearch_ngram' => [
+        'type' => 'text',
+        'index' => TRUE,
+        'boost' => $field->getBoost(),
+        'analyzer' => Ngram::PLUGIN_ID,
+      ],
+      'search_api_opensearch_edge_ngram' => [
+        'type' => 'text',
+        'index' => TRUE,
+        'boost' => $field->getBoost(),
+        'analyzer' => EdgeNgram::PLUGIN_ID,
+      ],
       'uri', 'string', 'token' => ['type' => 'keyword'],
       'integer', 'duration' => ['type' => 'integer'],
       'boolean' => ['type' => 'boolean'],

src/SearchAPI/IndexParamBuilder.php

@@ -116,7 +116,7 @@ class IndexParamBuilder {
     foreach ($field->getValues() as $value) {
       $values[] = match ($field_type) {
         'string' => (string) $value,
-        'text' => $value->toText(),
+        'text', 'search_api_opensearch_ngram', 'search_api_opensearch_edge_ngram' => $value->toText(),
         'boolean' => (boolean) $value,
         default => $value,
       };