feat: add no follow option in the links of Search Results Pager Block (Islandora#90)

Author: Aryan-R-Patel

config/schema/advanced_search.schema.yml

@@ -43,6 +43,9 @@ advanced_search.settings:
       sequence:
         type: string
         label: Field identifier
+    no_follow:
+      type: integer
+      label: Add rel="nofollow" attribute in links
 
 block.settings.search_block:
   type: block_settings

src/Form/SettingsForm.php

@@ -60,6 +60,8 @@ class SettingsForm extends ConfigFormBase {
 
   const QUERY_FIELDS = 'query_fields';
 
+  const NO_FOLLOW = 'no_follow';
+
   /**
    * {@inheritdoc}
    */
@@ -277,6 +279,19 @@ public function buildForm(array $form, FormStateInterface $form_state) {
       '#min' => 1,
     ];
 
+    /* -------------------------
+     * No follow option
+     * ------------------------- */
+    $form['no-follow'] = [
+      '#type' => 'fieldset',
+      '#title' => $this->t("No Follow Block"),
+    ];
+    $form['no-follow'][self::NO_FOLLOW] = [
+      '#type' => 'checkbox',
+      '#title' => $this->t('Add rel="nofollow" attribute in links'),
+      '#default_value' => self::getConfig(self::NO_FOLLOW, 0),
+    ];
+
     return parent::buildForm($form, $form_state);
   }
 
@@ -300,6 +315,7 @@ public function submitForm(array &$form, FormStateInterface $form_state) {
       ->set(self::DISPLAY_GRID_FLAG, $form_state->getValue(self::DISPLAY_GRID_FLAG))
       ->set(self::DISPLAY_DEFAULT, $form_state->getValue(self::DISPLAY_DEFAULT))
       ->set(self::QUERY_FIELDS, $query_fields)
+      ->set(self::NO_FOLLOW, $form_state->getValue(self::NO_FOLLOW))
       ->save();
 
     parent::submitForm($form, $form_state);

src/Plugin/Block/SearchResultsPagerBlock.php

@@ -236,6 +236,7 @@ protected function buildResultsSummary(ViewExecutable $view_executable) {
    *   A renderable array representing the results per page portion of pager.
    */
   protected function buildResultsPerPageLinks(SqlBase $pager, array $query_parameters) {
+    $config = $this->configFactory->get(SettingsForm::CONFIG_NAME);
     $active_items_per_page = $query_parameters['items_per_page'] ?? $pager->options['items_per_page'];
     $items_per_page_options = array_map(function ($value) {
       return trim($value);
@@ -252,7 +253,7 @@ protected function buildResultsPerPageLinks(SqlBase $pager, array $query_paramet
         'absolute' => TRUE,
       ]);
       $active = $items_per_page == $active_items_per_page;
-      $items[] = [
+      $item = [
         '#type' => 'link',
         '#url' => $url,
         '#title' => $items_per_page,
@@ -267,6 +268,10 @@ protected function buildResultsPerPageLinks(SqlBase $pager, array $query_paramet
           'class' => $active ? ['pager__item', 'is-active'] : ['pager__item'],
         ],
       ];
+      if (!empty($config->get(SettingsForm::NO_FOLLOW))) {
+        $item['#attributes']['rel'] = 'nofollow';
+      }
+      $items[] = $item;
     }
     return [
       '#theme' => 'item_list',
@@ -333,7 +338,7 @@ protected function buildDisplayLinks(array $query_parameters) {
       ]);
       $text = "<i class='fa {$options['icon']}' aria-hidden='true'>&nbsp;</i><span class='display-mode'>{$options['title']}</span>";
       $active = $active_display == $display;
-      $items[] = [
+      $item = [
         '#type' => 'link',
         '#url' => $url,
         '#title' => Markup::create($text),
@@ -348,6 +353,10 @@ protected function buildDisplayLinks(array $query_parameters) {
           'class' => $active ? ['pager__item', 'is-active'] : ['pager__item'],
         ],
       ];
+      if (!empty($config->get(SettingsForm::NO_FOLLOW))) {
+        $item['#attributes']['rel'] = 'nofollow';
+      }
+      $items[] = $item;
     }
 
     if (count($items) > 0) {