README.txt

@@ -4,9 +4,7 @@ CONTENTS OF THIS FILE
  * Requirements
  * Installation
  * Configuration
- * Troubleshooting
  * FAQ
- * Maintainers
 
  INTRODUCTION
  ------------
@@ -14,8 +12,9 @@ Todo
 
 REQUIREMENTS
 ------------
-No other modules required, though the module is useless without an implementing
-module like search api.
+No other modules required, we're supporting drupal core as a source for creating
+facets. Though we recommend using Search API, as that integration is better
+tested.
 
 INSTALLATION
 ------------
@@ -25,17 +24,14 @@ INSTALLATION
 
 CONFIGURATION
 -------------
-Todo
+Before adding a facet, there should be a facet source. Facet sources can be:
+- Drupal core's search.
+- A view based on a Search API index with a page display.
+- A page from the search_api_page module.
 
-TROUBLESHOOTING
----------------
-Todo
+After adding one of those, you can add a facet on the facets configuration page:
+/admin/config/search/facets
 
 FAQ
 ---
 Todo
-
-MAINTAINERS
------------
-Current maintainers:
- * Todo

config/schema/facets.facet.schema.yml

@@ -29,6 +29,9 @@ facets.facet.*:
     query_operator:
       type: string
       label: 'Query Operator'
+    exclude:
+      type: boolean
+      label: 'Exclude'
     widget:
       type: string
       label: 'Widget identifier'

facets.info.yml

@@ -4,3 +4,6 @@ description: 'Faceted search interfaces that can be used on Search API searchers
 core: 8.x
 package: Search
 configure: facets.overview
+test_dependencies:
+  - search_api:search_api
+  - drupal:views

src/Entity/Facet.php

@@ -44,6 +44,7 @@ use Drupal\facets\FacetInterface;
  *     "widget",
  *     "widget_configs",
  *     "query_operator",
+ *     "exclude",
  *     "only_visible_when_facet_source_is_visible",
  *     "processor_configs",
  *     "empty_behavior",
@@ -109,6 +110,13 @@ class Facet extends ConfigEntityBase implements FacetInterface {
    */
   protected $query_operator;
 
+  /**
+   * A boolean flag indicating if search should exclude selected facets.
+   *
+   * @var bool
+   */
+  protected $exclude;
+
   /**
    * The field identifier.
    *
@@ -363,6 +371,20 @@ class Facet extends ConfigEntityBase implements FacetInterface {
     return $this->query_operator ?: 'OR';
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function setExclude($exclude) {
+    return $this->exclude = $exclude;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getExclude() {
+    return $this->exclude;
+  }
+
   /**
    * {@inheritdoc}
    */

src/FacetInterface.php

@@ -164,6 +164,18 @@ interface FacetInterface extends ConfigEntityInterface {
    */
   public function getQueryOperator();
 
+  /**
+   * Returns the value of the exclude boolean.
+   *
+   * This will return true when the current facet's value should be exclusive
+   * from the search rather than inclusive.
+   * When this returns TRUE, the operator will be "<>" instead of "=".
+   *
+   * @return bool
+   *   A boolean flag indicating if search should exlude selected facets
+   */
+  public function getExclude();
+
   /**
    * Returns the plugin name for the url processor.
    *
@@ -193,6 +205,14 @@ interface FacetInterface extends ConfigEntityInterface {
    */
   public function setQueryOperator($operator);
 
+  /**
+   * Sets the exclude.
+   *
+   * @param bool $exclude
+   *   A boolean flag indicating if search should exclude selected facets
+   */
+  public function setExclude($exclude);
+
   /**
    * Returns the Facet source id.
    *

src/FacetManager/DefaultFacetManager.php

@@ -225,16 +225,13 @@ class DefaultFacetManager {
       $this->facets = $this->getEnabledFacets();
       foreach ($this->facets as $facet) {
 
-        foreach ($facet->getProcessors() as $processor) {
-          $processor_definition = $processor->getPluginDefinition();
-          if (is_array($processor_definition['stages']) && array_key_exists(ProcessorInterface::STAGE_PRE_QUERY, $processor_definition['stages'])) {
-            /** @var PreQueryProcessorInterface $pre_query_processor */
-            $pre_query_processor = $this->processorPluginManager->createInstance($processor->getPluginDefinition()['id'], ['facet' => $facet]);
-            if (!$pre_query_processor instanceof PreQueryProcessorInterface) {
-              throw new InvalidProcessorException(new FormattableMarkup("The processor @processor has a pre_query definition but doesn't implement the required PreQueryProcessorInterface interface", ['@processor' => $processor_configuration['processor_id']]));
-            }
-            $pre_query_processor->preQuery($facet);
+        foreach ($facet->getProcessorsByStage(ProcessorInterface::STAGE_PRE_QUERY) as $processor) {
+          /** @var PreQueryProcessorInterface $pre_query_processor */
+          $pre_query_processor = $this->processorPluginManager->createInstance($processor->getPluginDefinition()['id'], ['facet' => $facet]);
+          if (!$pre_query_processor instanceof PreQueryProcessorInterface) {
+            throw new InvalidProcessorException(new FormattableMarkup("The processor @processor has a pre_query definition but doesn't implement the required PreQueryProcessorInterface interface", ['@processor' => $processor_configuration['processor_id']]));
           }
+          $pre_query_processor->preQuery($facet);
         }
       }
     }
@@ -289,16 +286,13 @@ class DefaultFacetManager {
     // @see \Drupal\facets\Processor\WidgetOrderProcessorInterface.
     $results = $facet->getResults();
 
-    foreach ($facet->getProcessors() as $processor) {
-      $processor_definition = $this->processorPluginManager->getDefinition($processor->getPluginDefinition()['id']);
-      if (is_array($processor_definition['stages']) && array_key_exists(ProcessorInterface::STAGE_BUILD, $processor_definition['stages'])) {
-        /** @var BuildProcessorInterface $build_processor */
-        $build_processor = $this->processorPluginManager->createInstance($processor->getPluginDefinition()['id'], ['facet' => $facet]);
-        if (!$build_processor instanceof BuildProcessorInterface) {
-          throw new InvalidProcessorException(new FormattableMarkup("The processor @processor has a build definition but doesn't implement the required BuildProcessorInterface interface", ['@processor' => $processor['processor_id']]));
-        }
-        $results = $build_processor->build($facet, $results);
+    foreach ($facet->getProcessorsByStage(ProcessorInterface::STAGE_BUILD) as $processor) {
+      /** @var BuildProcessorInterface $build_processor */
+      $build_processor = $this->processorPluginManager->createInstance($processor->getPluginDefinition()['id'], ['facet' => $facet]);
+      if (!$build_processor instanceof BuildProcessorInterface) {
+        throw new InvalidProcessorException(new FormattableMarkup("The processor @processor has a build definition but doesn't implement the required BuildProcessorInterface interface", ['@processor' => $processor['processor_id']]));
       }
+      $results = $build_processor->build($facet, $results);
     }
     $facet->setResults($results);
 

src/Form/FacetDisplayForm.php

@@ -359,6 +359,13 @@ class FacetDisplayForm extends EntityForm {
       '#default_value' => $facet->getQueryOperator(),
     ];
 
+    $form['facet_settings']['exclude'] = [
+      '#type' => 'checkbox',
+      '#title' => $this->t('Exclude'),
+      '#description' => $this->t('Make the search exclude selected facets, instead of restricting it to them.'),
+      '#default_value' => $facet->getExclude(),
+    ];
+
     $form['weights'] = array(
       '#type' => 'details',
       '#title' => t('Advanced settings'),
@@ -537,6 +544,8 @@ class FacetDisplayForm extends EntityForm {
 
     $facet->setQueryOperator($form_state->getValue(['facet_settings', 'query_operator']));
 
+    $facet->setExclude($form_state->getValue(['facet_settings', 'exclude']));
+
     $facet->save();
     drupal_set_message(t('Facet %name has been updated.', ['%name' => $facet->getName()]));
   }

src/Form/FacetForm.php

@@ -221,6 +221,7 @@ class FacetForm extends EntityForm {
    * Handles form submissions for the facet source subform.
    */
   public function submitAjaxFacetSourceConfigForm($form, FormStateInterface $form_state) {
+    $form_state->setValue('id', NULL);
     $form_state->setRebuild();
   }
 
@@ -254,6 +255,20 @@ class FacetForm extends EntityForm {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    parent::validateForm($form, $form_state);
+
+    $facet_source_id = $form_state->getValue('facet_source_id');
+    if (!is_null($facet_source_id) && $facet_source_id !== '') {
+      /** @var \Drupal\facets\FacetSource\FacetSourcePluginInterface $facet_source */
+      $facet_source = $this->getFacetSourcePluginManager()->createInstance($facet_source_id, ['facet' => $this->getEntity()]);
+      $facet_source->validateConfigurationForm($form, $form_state);
+    }
+  }
+
   /**
    * {@inheritdoc}
    */

src/Plugin/facets/facet_source/SearchApiBaseFacetSource.php

@@ -98,7 +98,7 @@ abstract class SearchApiBaseFacetSource extends FacetSourcePluginBase {
     // identifier.
     $field_id = $facet->getFieldIdentifier();
     // Get the Search API Server.
-    $server = $this->index->getServer();
+    $server = $this->index->getServerInstance();
     // Get the Search API Backend.
     $backend = $server->getBackend();
 

src/Plugin/facets/query_type/SearchApiString.php

@@ -47,6 +47,7 @@ class SearchApiString extends QueryTypePluginBase {
     if (!empty($query)) {
       $operator = $this->facet->getQueryOperator();
       $field_identifier = $this->facet->getFieldIdentifier();
+      $exclude = $this->facet->getExclude();
 
       // Copy the query object so we can do an unfiltered query. We need to have
       // this unfiltered results to make sure that the count of a facet is
@@ -81,7 +82,7 @@ class SearchApiString extends QueryTypePluginBase {
       if (count($active_items)) {
         $filter = $query->createConditionGroup($operator);
         foreach ($active_items as $value) {
-          $filter->addCondition($this->facet->getFieldIdentifier(), $value);
+          $filter->addCondition($this->facet->getFieldIdentifier(), $value, $exclude ? '<>' : '=');
         }
         $query->addConditionGroup($filter);
       }

src/Tests/IntegrationTest.php

@@ -71,9 +71,10 @@ class IntegrationTest extends FacetWebTestBase {
     // Check if the overview is empty.
     $this->checkEmptyOverview();
 
-    // Add a new facet and edit it.
+    // Add a new facet and edit it. Check adding a duplicate.
     $this->addFacet($facet_name);
     $this->editFacet($facet_name);
+    $this->addFacetDuplicate($facet_name);
 
     // By default, the view should show all entities.
     $this->drupalGet('search-api-test-fulltext');
@@ -440,6 +441,52 @@ class IntegrationTest extends FacetWebTestBase {
     $this->assertOptionSelected('edit-processors-hide-non-narrowing-result-processor-weights-build', 5);
   }
 
+  /**
+   * Tests the facet's exclude functionality.
+   */
+  public function testExcludeFacet() {
+    $facet_name = 'test & facet';
+    $facet_id = 'test_facet';
+    $facet_edit_page = 'admin/config/search/facets/' . $facet_id . '/display';
+
+    $this->addFacet($facet_name);
+    $this->createFacetBlock($facet_id);
+
+    $this->drupalGet($facet_edit_page);
+    $this->assertNoFieldChecked('edit-facet-settings-exclude');
+    $this->drupalPostForm(NULL, ['facet_settings[exclude]' => TRUE], $this->t('Save'));
+    $this->assertResponse(200);
+    $this->assertFieldChecked('edit-facet-settings-exclude');
+
+    $this->drupalGet('search-api-test-fulltext');
+    $this->assertText('foo bar baz');
+    $this->assertText('foo baz');
+    $this->assertLink('item');
+
+    $this->clickLink('item');
+    $this->assertLink('(-) item');
+    $this->assertText('foo baz');
+    $this->assertText('bar baz');
+    $this->assertNoText('foo bar baz');
+
+    $this->drupalGet($facet_edit_page);
+    $this->drupalPostForm(NULL, ['facet_settings[exclude]' => FALSE], $this->t('Save'));
+    $this->assertResponse(200);
+    $this->assertNoFieldChecked('edit-facet-settings-exclude');
+
+    $this->drupalGet('search-api-test-fulltext');
+    $this->assertText('foo bar baz');
+    $this->assertText('foo baz');
+    $this->assertLink('item');
+
+    $this->clickLink('item');
+    $this->assertLink('(-) item');
+    $this->assertText('foo bar baz');
+    $this->assertText('foo test');
+    $this->assertText('bar');
+    $this->assertNoText('foo baz');
+  }
+
   /**
    * Deletes a facet block by id.
    *
@@ -602,6 +649,40 @@ class IntegrationTest extends FacetWebTestBase {
     $this->drupalGet('admin/config/search/facets');
   }
 
+  /**
+   * Tests creating a facet with an existing machine name.
+   *
+   * @param string $facet_name
+   *   The name of the facet.
+   */
+  protected function addFacetDuplicate($facet_name, $facet_type = 'type') {
+    $facet_id = $this->convertNameToMachineName($facet_name);
+
+    $facet_add_page = '/admin/config/search/facets/add-facet';
+    $this->drupalGet($facet_add_page);
+
+    $form_values = [
+      'name' => $facet_name,
+      'id' => $facet_id,
+      'url_alias' => $facet_id,
+      'facet_source_id' => 'search_api_views:search_api_test_view:page_1',
+    ];
+
+    $facet_source_configs['facet_source_configs[search_api_views:search_api_test_view:page_1][field_identifier]'] = $facet_type;
+
+    // Try to submit a facet with a duplicate machine name after form rebuilding
+    // via facet source submit.
+    $this->drupalPostForm(NULL, $form_values, $this->t('Configure facet source'));
+    $this->drupalPostForm(NULL, $form_values + $facet_source_configs, $this->t('Save'));
+    $this->assertText($this->t('The machine-readable name is already in use. It must be unique.'));
+
+    // Try to submit a facet with a duplicate machine name after form rebuilding
+    // via facet source submit using AJAX.
+    $this->drupalPostAjaxForm(NULL, $form_values, array('facet_source_configure' => t('Configure facet source')));
+    $this->drupalPostForm(NULL, $form_values + $facet_source_configs, $this->t('Save'));
+    $this->assertText($this->t('The machine-readable name is already in use. It must be unique.'));
+  }
+
   /**
    * Tests editing of a facet through the UI.
    *

tests/facets_search_api_dependency/config/install/views.view.search_api_test_views_fulltext.yml

@@ -19,8 +19,8 @@ display:
       query:
         type: search_api_query
         options:
-          search_api_bypass_access: false
-          entity_access: false
+          bypass_access: true
+          skip_access: true
           parse_mode: terms
       exposed_form:
         type: basic