Exclude all 404 errors from monolog - symfony

Question

Currently I have monolog sending me emails when there are errors. I found that 404 errors were just polluting my email and my provider ended up suspending my account due to the number of emails I sent myself. I decided to exclude all 404 errors because all of them were due to bots looking for vulnerabilities and not from clients.
Exclude code:
excluded_404s:
- ^/
The problem I'm seeing now is that symfony still logs 404 errors if the bots use http methods other than GET. My email is now polluted with entries like
HEAD :80/phpmyAdmin/
How can I exclude all 404 errors including those using http methods other than GET?
Edit:
Oh boy. Beginner mistake here. It seems that after my last deploy of the configuration I did not clear the prod cache and I'm figuring out that the config is cached. I'm using deployer to deploy my code updates but I guess the clear cache command is missing from it.

Answer 1

Symfony 4.1. upwords can can be configured to ignore HTTP Codes:
config/packages/monolog.yaml
monolog:
handlers:
main:
# ...
type: 'fingers_crossed'
excluded_http_codes: [404]
https://symfony.com/blog/new-in-symfony-4-1-ignore-specific-http-codes-from-logs

Answer 2

I know it is an old question, but it is the 1st one when googling.
Meanwhile I found a solution for symfony 3.4, if you need to exclude all 404 errors from your logs you can create an ExceptionListener and check if the exception is a NotFoundHttpException.
If it is the case, then just return a response so that the event is stopped and the logger will not handle the exception.
src/AppBundle/EventListener/ExceptionListener.php
namespace AppBundle\EventListener;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
class ExceptionListener
{
public function onKernelException(GetResponseForExceptionEvent $event)
{
$exception = $event->getException();
if (! $exception instanceof NotFoundHttpException) {
return;
}
$response = new Response($exception->getMessage(), $exception->getStatusCode());
// returning a response stop the event propagation
$event->setResponse($response);
}
}
src/AppBundle/Resources/config/services.yml
services:
app.exception.listener:
class: AppBundle\EventListener\ExceptionListener
tags:
- { name: kernel.event_listener, event: kernel.exception }

Answer 3

In Symfony 4/5 you can do:
<?php
declare(strict_types=1);
namespace App\EventListener;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\Event\ExceptionEvent;
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
class ExceptionListener
{
public function onKernelException(ExceptionEvent $event)
{
$exception = $event->getThrowable();
if ($exception instanceof NotFoundHttpException) {
$response = new Response($exception->getMessage(), $exception->getStatusCode());
$event->setResponse($response);
}
return;
}
}
and
App\EventListener\ExceptionListener:
tags:
- { name: kernel.event_listener, event: kernel.exception }