diff --git a/src/Controller/Api/TestController.php b/src/Controller/Api/TestController.php
index abb6e08..88332a6 100644
--- a/src/Controller/Api/TestController.php
+++ b/src/Controller/Api/TestController.php
@@ -136,7 +136,7 @@ private function getSampleMedia(string $testFile): MediaEntity
     private function getMediaById(string $fileName, Context $context): ?MediaEntity
     {
         $criteria = new Criteria();
-        //we use the fileName filter to add backward compatibility
+        // we use the fileName filter to add backward compatibility
         $criteria->addFilter(new EqualsFilter('fileName', $fileName));
 
         /** @var MediaCollection $entities */
diff --git a/src/Core/Media/MediaUrlLoader.php b/src/Core/Media/MediaUrlLoader.php
index ea9fc8a..327a55d 100644
--- a/src/Core/Media/MediaUrlLoader.php
+++ b/src/Core/Media/MediaUrlLoader.php
@@ -96,7 +96,7 @@ private function map(iterable $entities): array
                 }
 
                 if (!$thumbnail->has('width')) {
-                    //TODO: load it! it might be empty due to PartialDataLoading, maybe subscribe to partial.thumbnail.loaded
+                    // TODO: load it! it might be empty due to PartialDataLoading, maybe subscribe to partial.thumbnail.loaded
                     continue;
                 }
 
diff --git a/tests/unit/Core/Media/MediaUrlLoaderTest.php b/tests/unit/Core/Media/MediaUrlLoaderTest.php
new file mode 100644
index 0000000..56d49bd
--- /dev/null
+++ b/tests/unit/Core/Media/MediaUrlLoaderTest.php
@@ -0,0 +1,236 @@
+<?php declare(strict_types=1);
+
+namespace Frosh\ThumbnailProcessor\Tests\Unit\Core\Media;
+
+use Frosh\ThumbnailProcessor\Core\Media\MediaUrlGenerator;
+use Frosh\ThumbnailProcessor\Core\Media\MediaUrlLoader;
+use PHPUnit\Framework\TestCase;
+use Shopware\Core\Framework\DataAbstractionLayer\PartialEntity;
+use Shopware\Core\Framework\Uuid\Uuid;
+
+class MediaUrlLoaderTest extends TestCase
+{
+    public function testLoaded() {
+        $id = Uuid::randomHex();
+
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::once())
+            ->method('generate')
+            ->willReturn([$id => 'https://example.com/a0/image.jpg']);
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => $id,
+            'path' => 'a0/image.txt',
+            'private' => false,
+        ]);
+
+        static::assertFalse($entity->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertTrue($entity->has('url'));
+        static::assertSame('https://example.com/a0/image.jpg', $entity->get('url'));
+    }
+
+    public function testLoadedWithMissingPrivate() {
+        $id = Uuid::randomHex();
+
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::never())
+            ->method('generate')
+            ->willReturn([$id => 'https://example.com/a0/image.jpg']);
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => $id,
+            'path' => 'a0/image.txt',
+        ]);
+
+        static::assertFalse($entity->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertFalse($entity->has('url'));
+    }
+
+    public function testLoadedWithMissingUrlResult() {
+        $id = Uuid::randomHex();
+
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::once())
+            ->method('generate')
+            ->willReturn([]);
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => $id,
+            'path' => 'a0/image.txt',
+            'private' => false,
+        ]);
+
+        static::assertFalse($entity->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertFalse($entity->has('url'));
+    }
+
+    public function testLoadedWithMissingPathResult() {
+        $id = Uuid::randomHex();
+
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::never())
+            ->method('generate');
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => $id,
+            'private' => false,
+        ]);
+
+        static::assertFalse($entity->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertFalse($entity->has('url'));
+    }
+
+    public function testLoadedWithThumbnailHavingUrls() {
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::once())
+            ->method('generate')
+            ->willReturn([
+                '1' => 'https://example.com/a0/image.jpg?width=100',
+                '2' => 'https://example.com/a0/thumbnailimage.jpg?width=100',
+            ]);
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => '1',
+            'path' => 'a0/image.txt',
+            'private' => false,
+            'width' => 100,
+            'thumbnails' => [
+                (new PartialEntity())->assign([
+                    'id' => '2',
+                    'path' => 'a0/thumbnailimage.jpg',
+                    'width' => 100,
+                ]),
+            ],
+        ]);
+
+        static::assertFalse($entity->has('url'));
+        static::assertFalse($entity->get('thumbnails')[0]->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertTrue($entity->has('url'));
+        static::assertTrue($entity->get('thumbnails')[0]->has('url'));
+        static::assertSame('https://example.com/a0/thumbnailimage.jpg?width=100', $entity->get('thumbnails')[0]->get('url'));
+    }
+
+    public function testLoadedWithThumbnailHavingNoUrlsWithMissingWidth() {
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::once())
+            ->method('generate')
+            ->willReturn([
+                '1' => 'https://example.com/a0/image.jpg?width=100',
+            ]);
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => '1',
+            'path' => 'a0/image.txt',
+            'private' => false,
+            'thumbnails' => [
+                (new PartialEntity())->assign([
+                    'id' => '2',
+                    'path' => 'a0/thumbnailimage.jpg',
+                ]),
+            ],
+        ]);
+
+        static::assertFalse($entity->has('url'));
+        static::assertFalse($entity->get('thumbnails')[0]->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertTrue($entity->has('url'));
+        static::assertFalse($entity->get('thumbnails')[0]->has('url'));
+    }
+
+    public function testLoadedWithThumbnailHavingNoUrl() {
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::once())
+            ->method('generate')
+            ->willReturn([
+                '1' => 'https://example.com/a0/image.jpg',
+            ]);
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => '1',
+            'path' => 'a0/image.txt',
+            'private' => false,
+            'width' => 100,
+            'thumbnails' => [
+                (new PartialEntity())->assign([
+                    'id' => '2',
+                ]),
+            ],
+        ]);
+
+        static::assertFalse($entity->has('url'));
+        static::assertFalse($entity->get('thumbnails')[0]->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertTrue($entity->has('url'));
+        static::assertFalse($entity->get('thumbnails')[0]->has('url'));
+    }
+
+    /**
+     * @dataProvider provideInvalidThumbnailData
+     */
+    public function testLoadedWithNotIterableThumbnail(mixed $thumbnail) {
+        $mediaUrlGenerator = $this->createMock(MediaUrlGenerator::class);
+        $mediaUrlGenerator->expects(static::once())
+            ->method('generate')
+            ->willReturn([
+                '1' => 'https://example.com/a0/image.jpg',
+            ]);
+
+        $mediaUrlLoader = new MediaUrlLoader($mediaUrlGenerator);
+        $entity = new PartialEntity();
+        $entity->assign([
+            'id' => '1',
+            'path' => 'a0/image.txt',
+            'private' => false,
+            'width' => 100,
+            'thumbnails' => $thumbnail,
+        ]);
+
+        static::assertFalse($entity->has('url'));
+
+        $mediaUrlLoader->loaded([$entity]);
+
+        static::assertTrue($entity->has('url'));
+    }
+
+    public function provideInvalidThumbnailData(): iterable
+    {
+        yield [[]];
+        yield [[null]];
+        yield [''];
+        yield [['']];
+        yield [new PartialEntity()];
+    }
+}
\ No newline at end of file