[Messenger / Serializer] Conflict when serialize ErrorDetailsStamp

[Amorfx]

Symfony version(s) affected

6.2.5

Description

For reasons of compatibility with an external service, I had to develop a custom Transport serializer used by Symfony Messenger. Like the default Serializer i want to serialize all the stamps in Header.

But when an error occurs when it consume the message, I noticed a fatal error related to a warning in FlattenExceptionNormalizer : Warning: Undefined array key "message".

After debugging it would seem that when the serializer serializes data from a FlattenException class it would use ProblemNormalizer from Serializer component and not FlattenExceptionNormalizer from Messenger component. And so in the end the serialized data does not include the message and to denormalize it causes an error.

So I have to remove the ErrorDetailsStamp from the headers in the encode function for it to work.

How to reproduce

Create a custom Messenger serializer for transport :

declare(strict_types=1);


final class MessageSerializer implements SerializerInterface
{
    private const STAMP_HEADER_PREFIX = 'X-Message-Stamp-';

    public function __construct(
       // ...
        private readonly SymfonySerializer $serializer,
        // ...
        private array $context = []
    ) {
        $this->context = $context + [Serializer::MESSENGER_SERIALIZATION_CONTEXT => true];
    }

    /**
     * @param array{body: string, headers: array<string>, mixed} $encodedEnvelope
     *
     * @throws Exception
     */
    public function decode(array $encodedEnvelope): Envelope
    {
        $stamps = $this->decodeStamps($encodedEnvelope);
        $stamps[] = new SerializedMessageStamp($encodedEnvelope['body']);
// ...
        $command = $this->serializer->deserialize($encodedEnvelope['body'], $commandName, 'json');
//  ...
        return new Envelope($command, $stamps);
    }

    /**
     * Used only for retry
     *
     * @return array<string, mixed>
     *
     * @throws Exception
     */
    public function encode(Envelope $envelope): array
    {
        /** @var SerializedMessageStamp|null $serializedMessageStamp */
        $serializedMessageStamp = $envelope->last(SerializedMessageStamp::class);

        $envelope = $envelope
            ->withoutStampsOfType(NonSendableStampInterface::class);
            // ->withoutStampsOfType(ErrorDetailsStamp::class);

        return [
            'body' => $serializedMessageStamp->getSerializedMessage(),
            'headers' => [
                self::EVENT_NAME_KEY_HEADER => $eventNameStamp->getEventName(),
                'Content-Type' => 'application/json',
            ] + $this->encodeStamps($envelope),
        ];
    }

    /**
     * @param array{headers?: array<string>, mixed} $encodedEnvelope
     *
     * @return StampInterface[]
     */
    private function decodeStamps(array $encodedEnvelope): array
    {
        $stamps = [];
        if (!isset($encodedEnvelope['headers'])) {
            return $stamps;
        }

        foreach ($encodedEnvelope['headers'] as $name => $value) {
            if (!str_starts_with($name, self::STAMP_HEADER_PREFIX)) {
                continue;
            }

            $stamps[] = $this->serializer->deserialize($value, substr($name, strlen(self::STAMP_HEADER_PREFIX)) . '[]', 'json', $this->context);
        }
        if ($stamps) {
            $stamps = array_merge(...$stamps);
        }

        return $stamps;
    }

    /**
     * @return array<string, string>
     */
    private function encodeStamps(Envelope $envelope): array
    {
        if (!$allStamps = $envelope->all()) {
            return [];
        }

        $headers = [];
        foreach ($allStamps as $class => $stamps) {
            $headers[self::STAMP_HEADER_PREFIX . $class] = $this->serializer->serialize($stamps, 'json', $this->context);
        }

        return $headers;
    }
}

Possible Solution

No response

Additional Context

[fuduley1]

We experience similar issue with ErrorDetailsStamp. We have custom serializer which is almost the same as Amorfx's one. I get slightly different exception, though:

Failed to denormalize attribute "dataRepresentation" value for class "Symfony\Component\ErrorHandler\Exception\FlattenException": Expected argument of type "Symfony\Component\VarDumper\Cloner\Data", "null" given at property path "dataRepresentation". 

As a temporary solution, i removed "ErrorDetailsStamp"

[Amorfx]

Consequently I do not have all the details of the exceptions in the rejected messages it is quite problematic.

Any update ?

[carsonbot]

Hey, thanks for your report!
There has not been a lot of activity here for a while. Is this bug still relevant? Have you managed to find a workaround?

[Amorfx]

Yes its still relevant.