Issue #3232157 by Leon Kessler: Image styles are generated for other types of file entites

src/Plugin/Field/FieldType/ImageStyleNormalizedFieldItemList.php

@@ -21,24 +21,26 @@ protected function computeValue() {
     $config = \Drupal::config('jsonapi_image_styles.settings');
     $styles = [];
     $entity = $this->getEntity();
-    $uri = ($entity instanceof File) ? $entity->getFileUri() : FALSE;
-
-    $defined_styles = ($config->get('image_styles')) ? $config->get('image_styles') : [];
-    if (!empty(array_filter($defined_styles))) {
-      foreach ($defined_styles as $key) {
-        $styles[$key] = ImageStyle::load($key);
+    $uri = ($entity instanceof File && substr($entity->getMimeType(), 0, 5) === 'image') ? $entity->getFileUri() : FALSE;
+
+    if ($uri) {
+      $defined_styles = $config->get('image_styles') ?? [];
+      if (!empty(array_filter($defined_styles))) {
+        foreach ($defined_styles as $key) {
+          $styles[$key] = ImageStyle::load($key);
+        }
+      }
+      else {
+        $styles = ImageStyle::loadMultiple();
       }
-    }
-    else {
-      $styles = ImageStyle::loadMultiple();
-    }
 
-    $offset = 0;
-    foreach ($styles as $name => $style) {
-      if ($style instanceof ImageStyle) {
-        $this->list[] = $this->createItem($offset, ['url' => [$name => $style->buildUrl($uri)]]);
+      $offset = 0;
+      foreach ($styles as $name => $style) {
+        if ($style instanceof ImageStyle) {
+          $this->list[] = $this->createItem($offset, ['url' => [$name => $style->buildUrl($uri)]]);
+        }
+        $offset++;
       }
-      $offset++;
     }
   }