Issue #1868772 by tim.plunkett, sun, heyrocker: Convert filters to plugins.

core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorTest.php

@@ -107,7 +107,7 @@ function testGetJSSettings() {
     // Change the allowed HTML tags; the "format_tags" setting for CKEditor
     // should automatically be updated as well.
     $format = entity_load('filter_format', 'filtered_html');
-    $format->filters['filter_html']['settings']['allowed_html'] .= '<pre> <h3>';
+    $format->filters('filter_html')->settings['allowed_html'] .= '<pre> <h3>';
     $format->save();
     $expected_config['format_tags'] = 'p;h3;h4;h5;h6;pre';
     $this->assertEqual($expected_config, $this->ckeditor->getJSSettings($editor), 'Generated JS settings are correct for customized configuration.');

core/modules/filter/config/filter.format.plain_text.yml

@@ -15,12 +15,19 @@ filters:
   filter_html_escape:
     module: filter
     status: '1'
+    weight: '-10'
+    settings: {  }
   # Convert URLs into links.
   filter_url:
     module: filter
     status: '1'
+    weight: '0'
+    settings:
+      filter_url_length: '72'
   # Convert linebreaks into paragraphs.
   filter_autop:
     module: filter
     status: '1'
+    weight: '0'
+    settings: {  }
 langcode: und

core/modules/filter/filter.admin.inc

@@ -197,25 +197,9 @@ function filter_admin_format_form($form, &$form_state, $format) {
     $form['roles']['#default_value'] = array($admin_role);
   }
 
-  // Retrieve available filters and load all configured filters for existing
-  // text formats.
-  $filter_info = filter_get_filters();
-  $filters = !empty($format->format) ? filter_list_format($format->format) : array();
-
-  // Prepare filters for form sections.
-  foreach ($filter_info as $name => $filter) {
-    // Create an empty filter object for new/unconfigured filters.
-    if (!isset($filters[$name])) {
-      $filters[$name] = new stdClass();
-      $filters[$name]->format = $format->format;
-      $filters[$name]->module = $filter['module'];
-      $filters[$name]->name = $name;
-      $filters[$name]->status = 0;
-      $filters[$name]->weight = $filter['weight'];
-      $filters[$name]->settings = array();
-    }
-  }
-  $form['#filters'] = $filters;
+  // Create filter plugin instances for all available filters, including both
+  // enabled/configured ones as well as new and not yet unconfigured ones.
+  $filters = $format->filters()->sort();
 
   // Filter status.
   $form['filters']['status'] = array(
@@ -228,17 +212,6 @@ function filter_admin_format_form($form, &$form_state, $format) {
     // @see http://drupal.org/node/1829202
     '#input' => FALSE,
   );
-  foreach ($filter_info as $name => $filter) {
-    $form['filters']['status'][$name] = array(
-      '#type' => 'checkbox',
-      '#title' => $filter['title'],
-      '#default_value' => $filters[$name]->status,
-      '#parents' => array('filters', $name, 'status'),
-      '#description' => $filter['description'],
-      '#weight' => $filter['weight'],
-    );
-  }
-
   // Filter order (tabledrag).
   $form['filters']['order'] = array(
     '#type' => 'table',
@@ -252,48 +225,54 @@ function filter_admin_format_form($form, &$form_state, $format) {
     '#input' => FALSE,
     '#theme_wrappers' => array('form_element'),
   );
-  foreach ($filter_info as $name => $filter) {
+  // Filter settings.
+  $form['filter_settings'] = array(
+    '#type' => 'vertical_tabs',
+    '#title' => t('Filter settings'),
+  );
+
+  foreach ($filters as $name => $filter) {
+    $form['filters']['status'][$name] = array(
+      '#type' => 'checkbox',
+      '#title' => $filter->getLabel(),
+      '#default_value' => $filter->status,
+      '#parents' => array('filters', $name, 'status'),
+      '#description' => $filter->getDescription(),
+      '#weight' => $filter->weight,
+    );
+
     $form['filters']['order'][$name]['#attributes']['class'][] = 'draggable';
-    $form['filters']['order'][$name]['#weight'] = $filters[$name]->weight;
+    $form['filters']['order'][$name]['#weight'] = $filter->weight;
     $form['filters']['order'][$name]['filter'] = array(
-      '#markup' => $filter['title'],
+      '#markup' => $filter->getLabel(),
     );
     $form['filters']['order'][$name]['weight'] = array(
       '#type' => 'weight',
-      '#title' => t('Weight for @title', array('@title' => $filter['title'])),
+      '#title' => t('Weight for @title', array('@title' => $filter->getLabel())),
       '#title_display' => 'invisible',
       '#delta' => 50,
-      '#default_value' => $filters[$name]->weight,
+      '#default_value' => $filter->weight,
       '#parents' => array('filters', $name, 'weight'),
       '#attributes' => array('class' => array('filter-order-weight')),
     );
-  }
-  // Make sure filters are in the correct order, since filter_get_filters()
-  // doesn't return sorted filters.
-  uasort($form['filters']['order'], 'element_sort');
 
-  // Filter settings.
-  $form['filter_settings'] = array(
-    '#type' => 'vertical_tabs',
-    '#title' => t('Filter settings'),
-  );
-
-  foreach ($filter_info as $name => $filter) {
-    if (isset($filter['settings callback'])) {
-      $function = $filter['settings callback'];
-      // Pass along stored filter settings and default settings, but also the
-      // format object and all filters to allow for complex implementations.
-      $settings_form = $function($form, $form_state, $filters[$name], $format, $filter['default settings'], $filters);
-      if (!empty($settings_form)) {
-        $form['filters']['settings'][$name] = array(
-          '#type' => 'details',
-          '#title' => $filter['title'],
-          '#parents' => array('filters', $name, 'settings'),
-          '#weight' => $filter['weight'],
-          '#group' => 'filter_settings',
-        );
-        $form['filters']['settings'][$name] += $settings_form;
-      }
+    // Retrieve the settings form of the filter plugin. The plugin should not be
+    // aware of the text format. Therefore, it only receives a set of minimal
+    // base properties to allow advanced implementations to work.
+    $settings_form = array(
+      '#parents' => array('filters', $name, 'settings'),
+      '#tree' => TRUE,
+    );
+    $settings_form = $filter->settingsForm($settings_form, $form_state);
+    if (!empty($settings_form)) {
+      $form['filters']['settings'][$name] = array(
+        '#type' => 'details',
+        '#title' => $filter->getLabel(),
+        '#weight' => $filter->weight,
+        '#parents' => array('filters', $name, 'settings'),
+        '#group' => 'filter_settings',
+      );
+      $form['filters']['settings'][$name] += $settings_form;
     }
   }
 
@@ -337,7 +316,14 @@ function filter_admin_format_form_submit($form, &$form_state) {
   // Add the submitted form values to the text format, and save it.
   $format = $form['#format'];
   foreach ($form_state['values'] as $key => $value) {
-    $format->set($key, $value);
+    if ($key != 'filters') {
+      $format->set($key, $value);
+    }
+    else {
+      foreach ($value as $instance_id => $config) {
+        $format->setFilterConfig($instance_id, $config);
+      }
+    }
   }
   $status = $format->save();
 

core/modules/filter/filter.services.yml

@@ -10,3 +10,6 @@ services:
     class: Drupal\filter\Access\FormatDisableCheck
     tags:
       - { name: access_check }
+  plugin.manager.filter:
+    class: Drupal\filter\FilterPluginManager
+    arguments: ['@container.namespaces']

core/modules/filter/lib/Drupal/filter/Annotation/Filter.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\filter\Annotation\Filter.
+ */
+
+namespace Drupal\filter\Annotation;
+
+use Drupal\Component\Annotation\Plugin;
+
+/**
+ * Defines an filter annotation object.
+ *
+ * @Annotation
+ */
+class Filter extends Plugin {
+
+  public $title;
+  public $description = '';
+  public $weight = 0;
+  public $status = FALSE;
+  public $cache = TRUE;
+  public $settings = array();
+
+}

core/modules/filter/lib/Drupal/filter/FilterBag.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\filter\FilterBag.
+ */
+
+namespace Drupal\filter;
+
+use Drupal\Component\Plugin\PluginBag;
+use Drupal\Component\Plugin\PluginManagerInterface;
+use Drupal\Component\Plugin\Exception\PluginException;
+use Drupal\Component\Utility\NestedArray;
+
+/**
+ * A collection of filters.
+ */
+class FilterBag extends PluginBag {
+
+  /**
+   * The initial configuration for each filter in the bag.
+   *
+   * @var array
+   *   An associative array containing the initial configuration for each filter
+   *   in the bag, keyed by plugin instance ID.
+   */
+  protected $configurations = array();
+
+  /**
+   * The manager used to instantiate the plugins.
+   *
+   * @var \Drupal\Component\Plugin\PluginManagerInterface
+   */
+  protected $manager;
+
+  /**
+   * All possible filter plugin IDs.
+   *
+   * @var array
+   */
+  protected $definitions;
+
+  /**
+   * Constructs a FilterBag object.
+   *
+   * @param \Drupal\Component\Plugin\PluginManagerInterface $manager
+   *   The manager to be used for instantiating plugins.
+   * @param array $configurations
+   *   (optional) An associative array containing the initial configuration for
+   *   each filter in the bag, keyed by plugin instance ID.
+   */
+  public function __construct(PluginManagerInterface $manager, array $configurations = array()) {
+    $this->manager = $manager;
+    $this->configurations = $configurations;
+
+    if (!empty($configurations)) {
+      $this->instanceIDs = array_combine(array_keys($configurations), array_keys($configurations));
+    }
+  }
+
+  /**
+   * Retrieves filter definitions and creates an instance for each filter.
+   *
+   * This is exclusively used for the text format administration page, on which
+   * all available filter plugins are exposed, regardless of whether the current
+   * text format has an active instance.
+   *
+   * @todo Refactor text format administration to actually construct/create and
+   *   destruct/remove actual filter plugin instances, using a library approach
+   *   à la blocks.
+   */
+  public function getAll() {
+    // Retrieve all available filter plugin definitions.
+    if (!$this->definitions) {
+      $this->definitions = $this->manager->getDefinitions();
+    }
+
+    // Ensure that there is an instance of all available filters.
+    // Note that getDefinitions() are keyed by $plugin_id. $instance_id is the
+    // $plugin_id for filters, since a single filter plugin can only exist once
+    // in a format.
+    foreach ($this->definitions as $plugin_id => $definition) {
+      $this->initializePlugin($plugin_id);
+    }
+    return $this->pluginInstances;
+  }
+
+  /**
+   * Updates the configuration for a filter plugin instance.
+   *
+   * If there is no plugin instance yet, a new will be instantiated. Otherwise,
+   * the existing instance is updated with the new configuration.
+   *
+   * @param string $instance_id
+   *   The ID of a filter plugin to set the configuration for.
+   * @param array $configuration
+   *   The filter plugin configuration to set.
+   */
+  public function setConfig($instance_id, array $configuration) {
+    $this->configurations[$instance_id] = $configuration;
+    $this->get($instance_id)->setPluginConfiguration($configuration);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function initializePlugin($instance_id) {
+    // If the filter was initialized before, just return.
+    if (isset($this->pluginInstances[$instance_id])) {
+      return;
+    }
+
+    // Filters have a 1:1 relationship to text formats and can be added and
+    // instantiated at any time.
+    $definition = $this->manager->getDefinition($instance_id);
+
+    if (isset($definition)) {
+      $this->addInstanceID($instance_id);
+      // $configuration is the whole filter plugin instance configuration, as
+      // contained in the text format configuration. The default configuration
+      // is the filter plugin definition.
+      // @todo Configuration should not be contained in definitions. Move into a
+      //   FilterBase::init() method.
+      $configuration = $definition;
+      // Merge the actual configuration into the default configuration.
+      if (isset($this->configurations[$instance_id])) {
+        $configuration = NestedArray::mergeDeep($configuration, $this->configurations[$instance_id]);
+      }
+      $this->pluginInstances[$instance_id] = $this->manager->createInstance($instance_id, $configuration, $this);
+    }
+    else {
+      throw new PluginException(format_string("Unknown filter plugin ID '@filter'.", array('@filter' => $instance_id)));
+    }
+  }
+
+  /**
+   * Sorts all filter plugin instances in this bag.
+   *
+   * @return \Drupal\filter\FilterBag
+   */
+  public function sort() {
+    $this->getAll();
+    uasort($this->instanceIDs, array($this, 'sortHelper'));
+    return $this;
+  }
+
+  /**
+   * uasort() callback to sort filters by status, weight, module, and name.
+   *
+   * @see \Drupal\filter\FilterFormatStorageController::preSave()
+   */
+  public function sortHelper($aID, $bID) {
+    $a = $this->get($aID);
+    $b = $this->get($bID);
+    if ($a->status != $b->status) {
+      return !empty($a->status) ? -1 : 1;
+    }
+    if ($a->weight != $b->weight) {
+      return $a->weight < $b->weight ? -1 : 1;
+    }
+    if ($a->module != $b->module) {
+      return strnatcasecmp($a->module, $b->module);
+    }
+    return strnatcasecmp($a->getPluginId(), $b->getPluginId());
+  }
+
+  /**
+   * Returns the current configuration of all filters in this bag.
+   *
+   * @return array
+   *   An associative array keyed by filter plugin instance ID, whose values
+   *   are filter configurations.
+   *
+   * @see \Drupal\filter\Plugin\Filter\FilterInterface::export()
+   */
+  public function export() {
+    $filters = array();
+    $this->rewind();
+    foreach ($this as $instance_id => $instance) {
+      $filters[$instance_id] = $instance->export();
+    }
+    return $filters;
+  }
+
+}

core/modules/filter/lib/Drupal/filter/FilterFormatInterface.php

@@ -15,11 +15,28 @@
 interface FilterFormatInterface extends ConfigEntityInterface {
 
   /**
-   * Helper callback for uasort() to sort filters by status, weight, module, and name.
+   * Returns the collection of filter pugin instances or an individual plugin instance.
    *
-   * @see Drupal\filter\FilterFormatStorageController::preSave()
-   * @see filter_list_format()
+   * @param string $instance_id
+   *   (optional) The ID of a filter plugin instance to return.
+   *
+   * @return \Drupal\filter\FilterBag|\Drupal\filter\Plugin\FilterInterface
+   *   Either the filter bag or a specific filter plugin instance.
+   */
+  public function filters($instance_id = NULL);
+
+  /**
+   * Sets the configuration for a filter plugin instance.
+   *
+   * Sets or replaces the configuration of a filter plugin in $this->filters,
+   * and if instantianted already, also ensures that the actual filter plugin on
+   * the FilterBag contains the identical configuration.
+   *
+   * @param string $instance_id
+   *   The ID of a filter plugin to set the configuration for.
+   * @param array $configuration
+   *   The filter plugin configuration to set.
    */
-  public static function sortFilters($a, $b);
+  public function setFilterConfig($instance_id, array $configuration);
 
 }

core/modules/filter/lib/Drupal/filter/FilterFormatStorageController.php

@@ -22,45 +22,17 @@ protected function preSave(EntityInterface $entity) {
     parent::preSave($entity);
 
     $entity->name = trim($entity->label());
-    $entity->cache = _filter_format_is_cacheable($entity);
-    $filter_info = filter_get_filters();
-    foreach ($filter_info as $name => $filter) {
-      // Merge the actual filter definition into the filter default definition.
-      $defaults = array(
-        'module' => $filter['module'],
-        // The filter ID has to be temporarily injected into the properties, in
-        // order to sort all filters below.
-        // @todo Rethink filter sorting to remove dependency on filter IDs.
-        'name' => $name,
-        // Unless explicitly enabled, all filters are disabled by default.
-        'status' => 0,
-        // If no explicit weight was defined for a filter, assign either the
-        // default weight defined in hook_filter_info() or the default of 0 by
-        // filter_get_filters().
-        'weight' => $filter['weight'],
-        'settings' => $filter['default settings'],
-      );
-      // All available filters are saved for each format, in order to retain all
-      // filter properties regardless of whether a filter is currently enabled
-      // or not, since some filters require extensive configuration.
-      // @todo Do not save disabled filters whose properties are identical to
-      //   all default properties.
-      if (isset($entity->filters[$name])) {
-        $entity->filters[$name] = array_merge($defaults, $entity->filters[$name]);
-      }
-      else {
-        $entity->filters[$name] = $defaults;
-      }
-      // The module definition from hook_filter_info() always takes precedence
-      // and needs to be updated in case it changes.
-      $entity->filters[$name]['module'] = $filter['module'];
-    }
 
-    // Sort all filters.
-    uasort($entity->filters, 'Drupal\filter\Plugin\Core\Entity\FilterFormat::sortFilters');
-    // Remove the 'name' property from all filters that was added above.
-    foreach ($entity->filters as &$filter) {
-      unset($filter['name']);
+    // @todo Do not save disabled filters whose properties are identical to
+    //   all default properties.
+
+    // Determine whether the format can be cached.
+    // @todo This is a derived/computed definition, not configuration.
+    $entity->cache = TRUE;
+    foreach ($entity->filters() as $filter) {
+      if ($filter->status && !$filter->cache) {
+        $entity->cache = FALSE;
+      }
     }
   }
 

core/modules/filter/lib/Drupal/filter/FilterPluginManager.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\filter\FilterPluginManager.
+ */
+
+namespace Drupal\filter;
+
+use Drupal\Component\Plugin\PluginManagerBase;
+use Drupal\Component\Plugin\Factory\DefaultFactory;
+use Drupal\Core\Plugin\Discovery\AlterDecorator;
+use Drupal\Core\Plugin\Discovery\AnnotatedClassDiscovery;
+use Drupal\Core\Plugin\Discovery\CacheDecorator;
+
+/**
+ * Manages text processing filters.
+ *
+ * @see hook_filter_info_alter()
+ */
+class FilterPluginManager extends PluginManagerBase {
+
+  /**
+   * Constructs a FilterPluginManager object.
+   *
+   * @param \Traversable $namespaces
+   *   An object that implements \Traversable which contains the root paths
+   *   keyed by the corresponding namespace to look for plugin implementations.
+   */
+  public function __construct(\Traversable $namespaces) {
+    $annotation_namespaces = array('Drupal\filter\Annotation' => $namespaces['Drupal\filter']);
+    $this->discovery = new AnnotatedClassDiscovery('Filter', $namespaces, $annotation_namespaces, 'Drupal\filter\Annotation\Filter');
+    $this->discovery = new AlterDecorator($this->discovery, 'filter_info');
+    $this->discovery = new CacheDecorator($this->discovery, 'filter_plugins:' . language(LANGUAGE_TYPE_INTERFACE)->langcode, 'cache', array(
+      'filter_formats' => TRUE,
+    ));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function createInstance($plugin_id, array $configuration = array(), FilterBag $filter_bag = NULL) {
+    $plugin_definition = $this->discovery->getDefinition($plugin_id);
+    $plugin_class = DefaultFactory::getPluginClass($plugin_id, $plugin_definition);
+    return new $plugin_class($configuration, $plugin_id, $plugin_definition, $filter_bag);
+  }
+
+}

core/modules/filter/lib/Drupal/filter/Plugin/Core/Entity/FilterFormat.php

@@ -11,6 +11,7 @@
 use Drupal\Core\Entity\Annotation\EntityType;
 use Drupal\Core\Annotation\Translation;
 use Drupal\filter\FilterFormatInterface;
+use Drupal\filter\FilterBag;
 
 /**
  * Represents a text format.
@@ -98,24 +99,30 @@ class FilterFormat extends ConfigEntityBase implements FilterFormatInterface {
    * Configured filters for this text format.
    *
    * An associative array of filters assigned to the text format, keyed by the
-   * ID of each filter (prefixed with module name) and using the properties:
+   * instance ID of each filter and using the properties:
+   * - plugin_id: The plugin ID of the filter plugin instance.
    * - module: The name of the module providing the filter.
    * - status: (optional) A Boolean indicating whether the filter is
-   *   enabled in the text format. Defaults to disabled.
-   * - weight: (optional) The weight of the filter in the text format. If
-   *   omitted, the default value is determined in the following order:
-   *   - if any, the currently stored weight is retained.
-   *   - if any, the default weight from hook_filter_info() is taken over.
-   *   - otherwise, a default weight of 10, which usually sorts it last.
+   *   enabled in the text format. Defaults to FALSE.
+   * - weight: (optional) The weight of the filter in the text format. Defaults
+   *   to 0.
    * - settings: (optional) An array of configured settings for the filter.
-   *   See hook_filter_info() for details.
+   *
+   * Use FilterFormat::filters() to access the actual filters.
    *
    * @var array
    */
-  public $filters = array();
+  protected $filters = array();
+
+  /**
+   * Holds the collection of filters that are attached to this format.
+   *
+   * @var \Drupal\filter\FilterBag
+   */
+  protected $filterBag;
 
   /**
-   * Overrides \Drupal\Core\Entity\Entity::id().
+   * {@inheritdoc}
    */
   public function id() {
     return $this->format;
@@ -124,21 +131,40 @@ public function id() {
   /**
    * {@inheritdoc}
    */
-  public static function sortFilters($a, $b) {
-    if ($a['status'] != $b['status']) {
-      return !empty($a['status']) ? -1 : 1;
+  public function filters($instance_id = NULL) {
+    if (!isset($this->filterBag)) {
+      $this->filterBag = new FilterBag(\Drupal::service('plugin.manager.filter'), $this->filters);
     }
-    if ($a['weight'] != $b['weight']) {
-      return ($a['weight'] < $b['weight']) ? -1 : 1;
+    if (isset($instance_id)) {
+      return $this->filterBag->get($instance_id);
     }
-    if ($a['module'] != $b['module']) {
-      return strnatcasecmp($a['module'], $b['module']);
+    return $this->filterBag;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setFilterConfig($instance_id, array $configuration) {
+    $this->filters[$instance_id] = $configuration;
+    if (isset($this->filterBag)) {
+      $this->filterBag->setConfig($instance_id, $configuration);
     }
-    return strnatcasecmp($a['name'], $b['name']);
+    return $this;
   }
 
   /**
-   * Overrides \Drupal\Core\Config\Entity\ConfigEntityBase::disable().
+   * {@inheritdoc}
+   */
+  public function getExportProperties() {
+    $properties = parent::getExportProperties();
+    // Sort and export the configuration of all filters.
+    $properties['filters'] = $this->filters()->sort()->export();
+
+    return $properties;
+  }
+
+  /**
+   * {@inheritdoc}
    */
   public function disable() {
     parent::disable();

core/modules/filter/lib/Drupal/filter/Plugin/Filter/FilterAutoP.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\filter\Plugin\Filter\FilterAutoP.
+ */
+
+namespace Drupal\filter\Plugin\Filter;
+
+use Drupal\filter\Annotation\Filter;
+use Drupal\Core\Annotation\Translation;
+use Drupal\filter\Plugin\FilterBase;
+
+/**
+ * Provides a filter to conver line breaks to HTML.
+ *
+ * @Filter(
+ *   id = "filter_autop",
+ *   module = "filter",
+ *   title = @Translation("Convert line breaks into HTML (i.e. <code>&lt;br&gt;</code> and <code>&lt;p&gt;</code>)"),
+ *   type = FILTER_TYPE_MARKUP_LANGUAGE
+ * )
+ */
+class FilterAutoP extends FilterBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function process($text, $langcode, $cache, $cache_id) {
+    return _filter_autop($text);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function tips($long = FALSE) {