Fix for FingerprintPostController

backend/classes/controller/FingerprintPostController.php

@@ -17,6 +17,7 @@ final class FingerprintPostController extends AbstractController
         $db = new MySqlDatabase();
         $json = json_decode($this->requestBody);
         $fingerprint = new Fingerprint(null, $db);
+		$this->response = new ApiJsonResponse();
 
         try {
             $fingerprint->setFingerprint($json->fingerprint);
@@ -36,13 +37,10 @@ final class FingerprintPostController extends AbstractController
 
             $this->response->setParameter('fingerprintId', $fingerprint->getFingerprintId());
         } catch (QrCodeException $e) {
-            $db->rollback();
-
+        	$this->response->setStatus(ServerStatus::INTERNAL_ERROR);
             $this->response->setParameter('success', false);
-            $this->response->setStatus(ServerStatus::INTERNAL_ERROR);
-            $this->response->setMessage('An error occured during qr code creation!');
+            $this->response->setMessage('An error occured during QR code creation!');
         } catch (Throwable $e) {
-            $db->rollback();
             $this->catchDatabaseException($e->getMessage(), $json);
         }
     }

backend/classes/controller/FingerprintPutController.php

@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+final class FingerprintPutController extends AbstractController
+{
+	protected string $route = '/api/v1/fingerprint/{fingerprintId}';
+
+	private int $fingerprintId;
+
+	public function __construct(string $url)
+	{
+		parent::__construct($url);
+
+		$this->fingerprintId = (int)$this->getUrlParamInt('fingerprintId');
+	}
+
+	public function handle(): void
+	{
+		parent::handle();
+
+		if ($this->response->getStatus() !== ServerStatus::OK) {
+			return;
+		}
+
+		$this->response = new ApiJsonResponse();
+
+		try {
+			$json = json_decode($this->requestBody, true);
+			$fingerprint = new Fingerprint($this->fingerprintId);
+
+			if ($this->handleFingerprint($fingerprint, $json)) {
+				return;
+			}
+
+			$this->response->setMessage('Fingerprint did not differ from the stored. Nothing changed.');
+		} catch (Throwable $e) {
+			$this->response->setStatus(ServerStatus::BAD_REQUEST);
+			$this->response->setParameter('success', false);
+			$this->response->setMessage($e->getMessage());
+		}
+	}
+
+	public function handleFingerprint(Fingerprint $fingerprint, array $json): bool
+	{
+		if (isset($json['fingerprint'])) {
+			if ($fingerprint->getFingerprint() !== $json['fingerprint']) {
+				$fingerprint->setFingerprint($json['fingerprint']);
+				$fingerprint->Save();
+
+				return true;
+			}
+		}
+
+		return false;
+	}
+}