New error handler for API.

src/ApiErrorException.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace App;
+
+use App\DTO\ApiErrorMessage;
+use Symfony\Component\HttpKernel\Exception\HttpException;
+
+class ApiErrorException extends HttpException
+{
+
+    private ApiErrorMessage $apiErrorMsg;
+
+    public function __construct(ApiErrorMessage $apiErrorMsg, $detailsData = null, \Exception $previous = null, array $headers = array(), $code = 0)
+    {
+        $this->apiErrorMsg = $apiErrorMsg;
+
+        if (isset($detailsData)) {
+            $this->apiErrorMsg->setDetails($detailsData);
+        }
+
+        $statusCode = $apiErrorMsg->getStatusCode();
+        $message = $apiErrorMsg->getTitle();
+
+        parent::__construct($statusCode, $message, $previous, $headers, $code);
+    }
+
+    public function getApiErrorMsg(): ApiErrorMessage
+    {
+        return $this->apiErrorMsg;
+    }
+}

src/DTO/ApiErrorMessage.php

@@ -0,0 +1,80 @@
+<?php
+
+namespace App\DTO;
+
+use Symfony\Component\HttpFoundation\Response;
+
+class ApiErrorMessage
+{
+    const TYPE_VALIDATION_ERROR = 'validation_error';
+    const TYPE_INVALID_REQUEST_BODY_FORMAT = 'invalid_body_format';
+    const TYPE_LOGICAL_ERROR = 'logical_error';
+    const TYPE_SERVER_ERROR = 'server_error';
+    const TYPE_INVALID_DATE = 'invalid_date';
+
+    private static $titles = array(
+        self::TYPE_VALIDATION_ERROR => 'There was a validation error',
+        self::TYPE_INVALID_REQUEST_BODY_FORMAT => 'Invalid JSON format sent',
+        self::TYPE_LOGICAL_ERROR => 'Invalid request due to a logic error',
+        self::TYPE_SERVER_ERROR => 'Error on server side',
+        self::TYPE_INVALID_DATE => 'Invalid date on request',
+    );
+
+    private int $statusCode;
+    private string $type;
+    private string $title;
+    private array $extraData = array();
+
+    public function __construct($statusCode, $type = null)
+    {
+        if ($type === null) {
+            // no type? The default is about:blank and the title should
+            // be the standard status code message
+            $type = 'about:blank';
+            $title = isset(Response::$statusTexts[$statusCode]) ?
+                Response::$statusTexts[$statusCode] : 'Unknown status code :(';
+        } else {
+            if (!isset(self::$titles[$type])) {
+                throw new \InvalidArgumentException('No title for type ' . $type);
+            }
+            $title = self::$titles[$type];
+        }
+
+        $this->statusCode = $statusCode;
+        $this->type = $type;
+        $this->title = $title;
+    }
+
+    public function getStatusCode(): int
+    {
+        return $this->statusCode;
+    }
+
+    public function getTitle(): string
+    {
+        return $this->title;
+    }
+
+    public function setExtraData($name, $value)
+    {
+        $this->extraData[$name] = $value;
+    }
+
+    public function setDetails($value)
+    {
+        $this->extraData['details'] = $value;
+    }
+
+
+    public function toArray(): array
+    {
+        return array_merge(
+            $this->extraData,
+            array(
+                'status' => $this->statusCode,
+                'type' => $this->type,
+                'title' => $this->title,
+            )
+        );
+    }
+}

src/EventSubscriber/ApiExceptionSubscriber.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace App\EventSubscriber;
+
+use App\ApiErrorException;
+use App\DTO\ApiErrorMessage;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+use Symfony\Component\HttpKernel\Event\ExceptionEvent;
+use Symfony\Component\HttpKernel\KernelEvents;
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
+
+class ApiExceptionSubscriber implements EventSubscriberInterface
+{
+
+    public function __construct(
+        private LoggerInterface $logger,
+    ) {}
+
+    public function onKernelException(ExceptionEvent $event): void
+    {
+        $e = $event->getThrowable();
+        if ($e instanceof ApiErrorException) {
+            $apiErrorMsg = $e->getApiErrorMsg();
+        } else {
+            $statusCode = $e instanceof HttpExceptionInterface ? $e->getStatusCode() : 500;
+            $apiErrorMsg = new ApiErrorMessage($statusCode);
+
+            /*
+             * If it's an HttpException message (e.g. for 404, 403),
+             * we'll say as a rule that the exception message is safe
+             * for the client. Otherwise, it could be some sensitive
+             * low-level exception, which should *not* be exposed
+             */
+            if ($e instanceof HttpExceptionInterface) {
+                $apiErrorMsg->setExtraData('detail', $e->getMessage());
+            }
+        }
+
+        //Send error to logs.
+        $exceptionError = [
+            'message' => $e->getMessage(),
+            'file' => $e->getFile(),
+            'line' => $e->getLine(),
+            'trace' => $e->getTrace()
+        ];
+        $errorContext = array_merge($apiErrorMsg->toArray(), $exceptionError);
+        $this->logger->error("API ERROR Exception:", $errorContext);
+
+        //Send error to client.
+        $response = new JsonResponse(
+            $apiErrorMsg->toArray(),
+            $apiErrorMsg->getStatusCode()
+        );
+        $response->headers->set('Content-Type', 'application/problem+json');
+
+        $event->setResponse($response);
+    }
+
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            KernelEvents::EXCEPTION => 'onKernelException',
+        ];
+    }
+}