Add an index of reports at /report.

modules/core/report/farm_report.links.menu.yml

@@ -0,0 +1,4 @@
+farm.report:
+  title: Reports
+  parent: system.admin
+  route_name: farm.report

modules/core/report/farm_report.permissions.yml

@@ -0,0 +1,2 @@
+access farm report index:
+  title: 'Access report index'

modules/core/report/farm_report.routing.yml

@@ -0,0 +1,7 @@
+farm.report:
+  path: '/report'
+  defaults:
+    _controller: '\Drupal\farm_report\Controller\ReportController::index'
+    _title: 'Reports'
+  requirements:
+    _permission: 'access farm report index'

modules/core/report/src/Controller/ReportController.php

@@ -0,0 +1,97 @@
+<?php
+
+namespace Drupal\farm_report\Controller;
+
+use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Menu\MenuLinkTreeInterface;
+use Drupal\Core\Menu\MenuTreeParameters;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Report controller.
+ */
+class ReportController extends ControllerBase {
+
+  use StringTranslationTrait;
+
+  /**
+   * The menu link tree service.
+   *
+   * @var \Drupal\Core\Menu\MenuLinkTreeInterface
+   */
+  protected $menuLinkTree;
+
+  /**
+   * Constructs a new ReportController.
+   *
+   * @param \Drupal\Core\Menu\MenuLinkTreeInterface $menu_link_tree
+   *   The menu link tree service.
+   */
+  public function __construct(MenuLinkTreeInterface $menu_link_tree) {
+    $this->menuLinkTree = $menu_link_tree;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('menu.link_tree')
+    );
+  }
+
+  /**
+   * The index of reports.
+   *
+   * @return array
+   *   Returns a render array.
+   */
+  public function index(): array {
+
+    // Load all menu links below it.
+    $parameters = new MenuTreeParameters();
+    $parameters->setRoot('farm.report')->excludeRoot()->setTopLevelOnly()->onlyEnabledLinks();
+    $tree = $this->menuLinkTree->load(NULL, $parameters);
+    $manipulators = [
+      ['callable' => 'menu.default_tree_manipulators:checkAccess'],
+      ['callable' => 'menu.default_tree_manipulators:generateIndexAndSort'],
+    ];
+    $tree = $this->menuLinkTree->transform($tree, $manipulators);
+    $tree_access_cacheability = new CacheableMetadata();
+    $links = [];
+    foreach ($tree as $element) {
+      $tree_access_cacheability = $tree_access_cacheability->merge(CacheableMetadata::createFromObject($element->access));
+
+      // Only render accessible links.
+      if (!$element->access->isAllowed()) {
+        continue;
+      }
+
+      // Include the link.
+      $links[] = $element->link;
+    }
+    if (!empty($links)) {
+      $items = [];
+      foreach ($links as $link) {
+        $items[] = [
+          'title' => $link->getTitle(),
+          'description' => $link->getDescription(),
+          'url' => $link->getUrlObject(),
+        ];
+      }
+      $output = [
+        '#theme' => 'admin_block_content',
+        '#content' => $items,
+      ];
+    }
+    else {
+      $output = [
+        '#markup' => $this->t('You do not have any reports.'),
+      ];
+    }
+    return $output;
+  }
+
+}