Version 1
[yaffs-website] / web / core / modules / help / src / Plugin / Block / HelpBlock.php
diff --git a/web/core/modules/help/src/Plugin/Block/HelpBlock.php b/web/core/modules/help/src/Plugin/Block/HelpBlock.php
new file mode 100644 (file)
index 0000000..17dd88e
--- /dev/null
@@ -0,0 +1,115 @@
+<?php
+
+namespace Drupal\help\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Provides a 'Help' block.
+ *
+ * @Block(
+ *   id = "help_block",
+ *   admin_label = @Translation("Help")
+ * )
+ */
+class HelpBlock extends BlockBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * The current request.
+   *
+   * @var \Symfony\Component\HttpFoundation\Request
+   */
+  protected $request;
+
+  /**
+   * The current route match.
+   *
+   * @var \Drupal\Core\Routing\RouteMatchInterface
+   */
+  protected $routeMatch;
+
+  /**
+   * Creates a HelpBlock instance.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The current request.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
+   *   The current route match.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, Request $request, ModuleHandlerInterface $module_handler, RouteMatchInterface $route_match) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->request = $request;
+    $this->moduleHandler = $module_handler;
+    $this->routeMatch = $route_match;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('request_stack')->getCurrentRequest(),
+      $container->get('module_handler'),
+      $container->get('current_route_match')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    // Do not show on a 403 or 404 page.
+    if ($this->request->attributes->has('exception')) {
+      return [];
+    }
+
+    $implementations = $this->moduleHandler->getImplementations('help');
+    $build = [];
+    $args = [
+      $this->routeMatch->getRouteName(),
+      $this->routeMatch,
+    ];
+    foreach ($implementations as $module) {
+      // Don't add empty strings to $build array.
+      if ($help = $this->moduleHandler->invoke($module, 'help', $args)) {
+        // Convert strings to #markup render arrays so that they will XSS admin
+        // filtered.
+        $build[] = is_array($help) ? $help : ['#markup' => $help];
+      }
+    }
+    return $build;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    return Cache::mergeContexts(parent::getCacheContexts(), ['route']);
+  }
+
+}