Added special logic for showing redirect metadata view.

config/optional/views.view.quant_metadata_redirect.yml

@@ -655,7 +655,7 @@ display:
     position: 1
     display_options:
       display_extenders: {  }
-      path: admin/config/quant/metadata/redirect
+      path: admin/config/quant/metadata/redirectview
     cache_metadata:
       max-age: -1
       contexts:

quant.links.task.yml

@@ -42,7 +42,7 @@ quant.metadata_file:
   weight: 30
 
 quant.metadata_redirect:
-  route_name: view.quant_metadata_redirect.quant_metadata_redirect_page
+  route_name: quant.metadata_redirect
   title: 'Redirect Metadata'
   parent_id: quant.metadata
   weight: 40

quant.routing.yml

@@ -22,6 +22,14 @@ quant.metadata:
   requirements:
     _permission: 'configure quant'
 
+quant.metadata_redirect:
+  path: '/admin/config/quant/metadata/redirect'
+  defaults:
+    _controller: '\Drupal\quant\Page\QuantRedirectMetadata::build'
+    _title: 'Redirect Metadata'
+  requirements:
+    _permission: 'configure quant'
+
 quant.queue:
   path: '/admin/config/quant/queue-info'
   defaults:

src/Page/QuantRedirectMetadata.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace Drupal\quant\Page;
+
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\views\Views;
+
+/**
+ * Page controller for the redirect metadata page.
+ */
+class QuantRedirectMetadata extends ControllerBase {
+
+  /**
+   * Page callback for the redirect metadata page.
+   *
+   * If the redirect module is enabled and the metadata view exists, then show
+   * the view. Otherwise, show a help message.
+   *
+   * @return array
+   *   A render array.
+   */
+  public function build() {
+
+    $view = NULL;
+    $message = '';
+    // Check module is installed.
+    if (!\Drupal::moduleHandler()->moduleExists('redirect')) {
+      $message = $this->t('The redirect module is not enabled.');
+    }
+    // Check view is found.
+    else {
+      $view = Views::getView('quant_metadata_redirect');
+      if (!$view) {
+        $message = $this->t('The redirect metadata view was not found.');
+      }
+    }
+
+    // Show message.
+    if (!empty($message)) {
+      $build['info'] = [
+        '#type' => 'markup',
+        '#markup' => $message,
+      ];
+      return $build;
+    }
+
+    // Render the view display.
+    //$output = views_embed_view('quant_metadata_redirect', 'quant_metadata_redirect_page');
+    $view->setDisplay('quant_metadata_redirect_page');
+    $view->preExecute();
+    $view->execute();
+
+    return $view->buildRenderable();
+  }
+
+}