add logger, check if responsive_image style is set

src/Plugin/Field/FieldFormatter/BgImgFieldFormatter.php

@@ -10,6 +10,13 @@ use Drupal\image\Entity\ImageStyle;
 use Drupal\responsive_image\Plugin\Field\FieldFormatter\ResponsiveImageFormatter;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
 use Drupal\bg_img_field\Component\Render\CSSSnippet;
+use Drupal\Core\Logger\LoggerChannelTrait;
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Utility\LinkGeneratorInterface;
+use Drupal\Core\Session\AccountInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Core\Url;
 
 /**
  * Plugin implementation of the 'image' formatter.
@@ -27,6 +34,49 @@ use Drupal\bg_img_field\Component\Render\CSSSnippet;
  */
 class BgImgFieldFormatter extends ResponsiveImageFormatter implements ContainerFactoryPluginInterface {
 
+  /**
+   * @var Drupal\Core\Logger\LoggerChannelTrait
+   */
+  use LoggerChannelTrait;
+
+  public function __construct(
+    $plugin_id,
+    $plugin_definition,
+    FieldDefinitionInterface $field_definition,
+    array $settings,
+    $label,
+    $view_mode,
+    array $third_party_settings,
+    EntityStorageInterface $responsive_image_style_storage,
+    EntityStorageInterface $image_style_storage,
+    LinkGeneratorInterface $link_generator,
+    AccountInterface $current_user
+  ) {
+    parent::__construct(
+      $plugin_id,
+      $plugin_definition,
+      $field_definition,
+      $settings,
+      $label,
+      $view_mode,
+      $third_party_settings,
+      $responsive_image_style_storage,
+      $image_style_storage,
+      $link_generator,
+      $current_user
+    );
+
+    $this->logger = $this->getLogger('bg_img_field');
+  }
+
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+
+    $container = parent::create($container, $configuration, $plugin_id, $plugin_definition);
+
+    return $container;
+
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -179,47 +229,75 @@ class BgImgFieldFormatter extends ResponsiveImageFormatter implements ContainerF
     $css .= "background-position: " . $options['css_background_position'] .";";
     $css .= '}';
 
-    $breakpoints = \Drupal::service('breakpoint.manager')->getBreakpointsByGroup($responsive_image_style->getBreakpointGroup());
-    foreach (array_reverse($responsive_image_style->getKeyedImageStyleMappings()) as $breakpoint_id => $multipliers) {
-      if (isset($breakpoints[$breakpoint_id])) {
+    // $responsive_image_style holds the configuration from the responsive_image module for a given responsive style
+    // We need to check that this exists or else we get a WSOD
+    if (!$responsive_image_style) {
+      $field_definition = $this->fieldDefinition->getFieldStorageDefinition();
 
-        $multipliers = array_reverse($multipliers);
-
-        $query = $breakpoints[$breakpoint_id]->getMediaQuery();
-        if ($query != "") {
-          $css .= ' @media ' . $query . ' {';
-        }
+      $this->logger->error('
+        There is no responsive image style set for the {field_name} field on the {entity_type} entity. Please ensure
+        that the responsive image style is configured at <a href="{link}">{link}</a>.  Then set the correct style on the
+        formatter for the entity display.
+      ', [
+        'field_name' => $field_definition->get('field_name'),
+        'entity_type' => $field_definition->get('entity_type'),
+        'link' => Url::fromRoute('entity.responsive_image_style.collection')->toString()
+      ]);
+    }
+    else {
+      $breakpoints = \Drupal::service('breakpoint.manager')->getBreakpointsByGroup($responsive_image_style->getBreakpointGroup());
+      foreach (array_reverse($responsive_image_style->getKeyedImageStyleMappings()) as $breakpoint_id => $multipliers) {
+        if (isset($breakpoints[$breakpoint_id])) {
 
-        foreach ($multipliers as $multiplier => $mapping) {
-          $multiplier = rtrim($multiplier, "x");
+          $multipliers = array_reverse($multipliers);
 
-          if($mapping['image_mapping_type'] != 'image_style') {
-            continue;
+          $query = $breakpoints[$breakpoint_id]->getMediaQuery();
+          if ($query != "") {
+            $css .= ' @media ' . $query . ' {';
           }
 
-          if ($mapping['image_mapping'] == "_original image_") {
-            $url = file_create_url($image->getFileUri());
-          }
-          else {
-            $url = ImageStyle::load($mapping['image_mapping'])->buildUrl($image->getFileUri());
-          }
+          foreach ($multipliers as $multiplier => $mapping) {
+            $multiplier = rtrim($multiplier, "x");
+
+            if($mapping['image_mapping_type'] != 'image_style') {
+              continue;
+            }
 
-          if ($multiplier != 1) {
-            $css .= ' @media (-webkit-min-device-pixel-ratio: ' . $multiplier . '), (min-resolution: ' . $multiplier * 96 . 'dpi), (min-resolution: ' . $multiplier . 'dppx) {';
+            if ($mapping['image_mapping'] == "_original image_") {
+              $url = file_create_url($image->getFileUri());
+            }
+            else {
+              $url = ImageStyle::load($mapping['image_mapping'])->buildUrl($image->getFileUri());
+            }
+
+            if ($multiplier != 1) {
+              $css .= ' @media (-webkit-min-device-pixel-ratio: ' . $multiplier . '), (min-resolution: ' . $multiplier * 96 . 'dpi), (min-resolution: ' . $multiplier . 'dppx) {';
+            }
+            $css .= $selector . ' {background-image: url(' . $url . ');}';
+
+            if ($multiplier != 1) {
+              $css .= '}';
+            }
           }
-          $css .= $selector . ' {background-image: url(' . $url . ');}';
 
-          if ($multiplier != 1) {
+          if ($query != "") {
             $css .= '}';
           }
         }
-
-        if ($query != "") {
-          $css .= '}';
-        }
       }
     }
 
     return $css;
   }
+
+  /**
+   * Implement abstract method
+   *
+   * @param $level
+   * @param $message
+   * @param array $context
+   */
+  public function log($level, $message, array $context = []) {
+
+  }
 }