Library error: a socket error occurred in Symfony Messenger - php

Question

In my Symfony project, there is a queue message handler, and I have an error that randomly appears during the execution:
[2022-10-12T07:31:40.060119+00:00] console.CRITICAL: Error thrown while running command "messenger:consume async --limit=10". Message: "Library error: a socket error occurred" {"exception":"[object] (Symfony\\Component\\Messenger\\Exception
TransportException(code: 0): Library error: a socket error occurred at /var/www/app/vendor/symfony/amqp-messenger/Transport/AmqpReceiver.php:62)
[previous exception] [object] (AMQPException(code: 0): Library error: a socket error occurred at /var/www/app/vendor/symfony/amqp-messenger/Transport/Connection.php:439)","command":"messenger:consume async --limit=10","message":"Library error: a socket error occurred"} []
The handler executes HTTP requests that could last some seconds and the whole process of a single message could even take more than one minute if APIs are slow. The strange thing is that the problem disappears for hours but then it randomly appears again. The more messages are sent to the queue, the easier it's to see the exception.
config\packages\messenger.yaml
framework:
messenger:
transports:
# https://symfony.com/doc/current/messenger.html#transport-configuration
async:
dsn: "%env(MESSENGER_TRANSPORT_DSN)%"
options:
exchange:
name: async_exchange
queues:
async: ~
heartbeat: 45
write_timeout: 90
read_timeout: 90
retry_strategy:
max_retries: 0
routing:
# Route your messages to the transports
'App\Message\MessageUpdateRequest': async
App\MessageHandler\MessageUpdateRequestHandler.php
<?php
declare(strict_types=1);
namespace App\MessageHandler;
use App\Message\MessageUpdateRequest;
use Symfony\Component\Messenger\Handler\MessageHandlerInterface;
class MessageUpdateRequestHandler implements MessageHandlerInterface
{
public function __invoke(MessageUpdateRequest $message)
{
// Logic executing API requests...
return 0;
}
}
Environment
Symfony Messenger: 5.4.17
PHP: 8.1
RabbitMQ: 3.11.5
Things that I tried
upgrading Symfony Messenger to 5.4.17, using the fix available here;
adding the following options: heartbeat, write_timeout and read_timeout in the messenger.yaml file.
Related issues/links
https://github.com/php-amqp/php-amqp/issues/258
https://github.com/symfony/symfony/issues/32357
https://github.com/symfony/symfony/pull/47831
How can I fix this issue?

Answer 1

Regarding a socket error that occurs in Symfony Messenger, I always suggest following the step-wise approach and checking if you are missing anything. It should fix this type of error almost every time. Please follow these guidelines:
Verify that the RabbitMQ service is active and accessible.
Verify that the hostname, port, username, and password are listed in the messenger.yaml file are accurate.
In the messenger.yaml file, increase the heartbeat, write timeout, and read timeout settings.
Verify your use case to determine whether the max retries number in messenger.yaml is appropriate.
Look for any network problems that could be causing the socket error.
Make sure your PHP version is compatible with RabbitMQ and Symfony Messenger.
Verify that the server's resources (CPU, Memory, and Disk) are not used up.
Look for any relevant error messages in the PHP error log.
Determine whether there is a problem with the MessageUpdateRequestHandler class's logic.
Tip: Still stuck? Try to reproduce the error with a smaller message set and in a controlled environment to isolate the root cause that we may be missing.
Hope it helps. Happy debugging and good luck.