From e3ede9464301b18d25d2eb39ee83cb048c9bf9e7 Mon Sep 17 00:00:00 2001
From: Mark Wienk <mark@wienkit.nl>
Date: Wed, 19 Jul 2017 14:15:01 +0200
Subject: [PATCH] Added caching support

---
 src/Plugin/views/area/SpellCheck.php | 81 ++++++++++++++++++++++------
 1 file changed, 65 insertions(+), 16 deletions(-)

diff --git a/src/Plugin/views/area/SpellCheck.php b/src/Plugin/views/area/SpellCheck.php
index 515aa7c..59141fc 100644
--- a/src/Plugin/views/area/SpellCheck.php
+++ b/src/Plugin/views/area/SpellCheck.php
@@ -2,10 +2,13 @@
 
 namespace Drupal\search_api_spellcheck\Plugin\views\area;
 
+use Drupal\Core\Cache\Cache;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Url;
 use Drupal\search_api\Plugin\views\filter\SearchApiFulltext;
+use Drupal\search_api\Query\ResultSetInterface;
 use Drupal\views\Plugin\views\area\AreaPluginBase;
+use Drupal\views\Views;
 
 /**
  * Provides an area for messages.
@@ -16,6 +19,14 @@
  */
 class SpellCheck extends AreaPluginBase {
 
+  const SPELLCHECK_CACHE_SUFFIX = ":spellcheck";
+  const SPELLCHECK_CACHE_BIN = "data";
+
+  /**
+   * @var \Drupal\views\Plugin\views\cache\CachePluginBase
+   */
+  private $cache;
+
   /**
    * The available filters for the current view.
    *
@@ -47,15 +58,15 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
     parent::buildOptionsForm($form, $form_state);
 
     $form['search_api_spellcheck_title'] = array(
-      '#type' => 'textfield',
-      '#title' => $this->t('The title to announce the suggestions. Default: suggestions:'),
-      '#default_value' => isset($this->options['search_api_spellcheck_title']) ? $this->options['search_api_spellcheck_title'] : '',
+        '#type' => 'textfield',
+        '#title' => $this->t('The title to announce the suggestions. Default: suggestions:'),
+        '#default_value' => isset($this->options['search_api_spellcheck_title']) ? $this->options['search_api_spellcheck_title'] : '',
     );
 
     $form['search_api_spellcheck_hide_on_result'] = array(
-      '#type' => 'checkbox',
-      '#title' => $this->t('Hide when the view has results.'),
-      '#default_value' => isset($this->options['search_api_spellcheck_hide_on_result']) ? $this->options['search_api_spellcheck_hide_on_result'] : TRUE,
+        '#type' => 'checkbox',
+        '#title' => $this->t('Hide when the view has results.'),
+        '#default_value' => isset($this->options['search_api_spellcheck_hide_on_result']) ? $this->options['search_api_spellcheck_hide_on_result'] : TRUE,
     );
   }
 
@@ -69,6 +80,45 @@ public function preQuery() {
     parent::preQuery();
   }
 
+  /**
+   * @return mixed
+   */
+  protected function getCache()
+  {
+    if(!$this->cache) {
+      if (!empty($this->live_preview)) {
+        $this->cache = Views::pluginManager('cache')->createInstance('none');
+      } else {
+        $this->cache = $this->view->display_handler->getPlugin('cache');
+      }
+    }
+    return $this->cache;
+  }
+
+  /**
+   * Saves the solr response to the cache
+   * @param $values
+   */
+  public function postExecute(&$values)
+  {
+    /** @var ResultSetInterface $result */
+    $result = $this->query->getSearchApiResults();
+    $response = $result->getExtraData('search_api_solr_response');
+    $tags = $this->getCache()->getCacheTags();
+    \Drupal::cache(self::SPELLCHECK_CACHE_BIN)->set($this->getCacheKey(), $response, Cache::PERMANENT, $tags);
+    parent::postExecute($values);
+  }
+
+  /**
+   * Returns a generated cache key (based on the views cache key)
+   * @return string
+   */
+  public function getCacheKey()
+  {
+    $cache = $this->getCache();
+    return $cache->generateResultsKey() . self::SPELLCHECK_CACHE_SUFFIX;
+  }
+
   /**
    * Render the area.
    *
@@ -80,13 +130,12 @@ public function preQuery() {
    */
   public function render($empty = FALSE) {
     if ($this->options['search_api_spellcheck_hide_on_result'] == FALSE || ($this->options['search_api_spellcheck_hide_on_result'] && $empty)) {
-      $result = $this->query->getSearchApiResults();
-      // Check if extraData is there.
-      if ($extra_data = $result->getExtraData('search_api_solr_response')) {
+      $cacheItem = \Drupal::cache(self::SPELLCHECK_CACHE_BIN)->get($this->getCacheKey());
+      if ($extra_data = $cacheItem->data) {
         // Initialize our array.
         $suggestions = [];
         // Check that we have suggestions.
-        if (!empty($extra_data['spellcheck'])) {
+        if (!empty($extra_data['spellcheck']) && !empty($extra_data['spellcheck']['suggestions'])) {
           // Loop over the suggestions and print them as links.
           foreach ($extra_data['spellcheck'] as $suggestion) {
             // If we have a match within our filters we add the suggestion.
@@ -97,18 +146,18 @@ public function render($empty = FALSE) {
               }
               // Add the suggestion.
               $suggestions[] = [
-                '#type' => 'link',
-                '#title' => reset($filter),
-                '#url' => Url::fromRoute('<current>', [], ['query' => $filter]),
+                  '#type' => 'link',
+                  '#title' => reset($filter),
+                  '#url' => Url::fromRoute('<current>', [], ['query' => $filter]),
               ];
             }
           }
         }
         if (!empty($suggestions)) {
           return [
-            '#title' => $this->getSuggestionLabel(),
-            '#theme' => 'item_list',
-            '#items' => $suggestions,
+              '#title' => $this->getSuggestionLabel(),
+              '#theme' => 'item_list',
+              '#items' => $suggestions,
           ];
         }
       }