Improve ImageController error handling

00-backend/src/main/java/de/htwsaar/webshop/controller/ImageController.java

@@ -7,6 +7,7 @@ import de.htwsaar.webshop.service.ValidatorService;
 import jakarta.servlet.http.HttpServletRequest;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
@@ -34,14 +35,22 @@ public class ImageController {
     public ResponseEntity<List<ImageModel>> getAll(HttpServletRequest request,
                                                    @RequestParam(value = PARAM_ARTICLE_ID) Long articleId) {
         logRequest(request);
-        return ResponseEntity.ok(imageService.from(imageService.getImagesByArticleId(articleId)));
+        List<Image> images = imageService.getImagesByArticleId(articleId);
+        if(images.isEmpty()) {
+            return new ResponseEntity<>(HttpStatus.NO_CONTENT);
+        }
+        return ResponseEntity.ok(imageService.from(images));
     }
 
     @RequestMapping(path = IMAGE_BASE, method = RequestMethod.GET, produces = "application/json")
     public ResponseEntity<ImageModel> getFirst(HttpServletRequest request,
                                                @RequestParam(value = PARAM_ARTICLE_ID) Long articleId) {
         logRequest(request);
-        return ResponseEntity.ok(imageService.from(imageService.getImageByArticleId(articleId)));
+        Image image = imageService.getImageByArticleId(articleId);
+        if(image == null) {
+            return new ResponseEntity<>(HttpStatus.NO_CONTENT);
+        }
+        return ResponseEntity.ok(imageService.from(image));
     }
 
     @RequestMapping(path = IMAGE_BASE, method = RequestMethod.POST, produces = "application/json")