How to Configure Monolog to Exclude 404 Errors from the Log

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How to Configure Monolog to Exclude 404 Errors from the Log

Sometimes your logs become flooded with unwanted 404 HTTP errors, for example, when an attacker scans your app for some well-known application paths (e.g. `/phpmyadmin`). When using a fingers_crossed handler, you can exclude logging these 404 errors based on a regular expression in the MonologBundle configuration:

YAML
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PHP

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        # app/config/config.yml
monolog:
    handlers:
        main:
            # ...
            type: fingers_crossed
            handler: ...
            excluded_404s:
                - ^/phpmyadmin
    

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        <!-- app/config/config.xml -->
<container xmlns="http://symfony.com/schema/dic/services"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:monolog="http://symfony.com/schema/dic/monolog"
    xsi:schemaLocation="http://symfony.com/schema/dic/services
        http://symfony.com/schema/dic/services/services-1.0.xsd
        http://symfony.com/schema/dic/monolog
        http://symfony.com/schema/dic/monolog/monolog-1.0.xsd">

    <monolog:config>
        <monolog:handler type="fingers_crossed" name="main" handler="...">
            <!-- ... -->
            <monolog:excluded-404>^/phpmyadmin</monolog:excluded-404>
        </monolog:handler>
    </monolog:config>
</container>
    

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        // app/config/config.php
$container->loadFromExtension('monolog', array(
    'handlers' => array(
        'main' => array(
            // ...
            'type'          => 'fingers_crossed',
            'handler'       => ...,
            'excluded_404s' => array(
                '^/phpmyadmin',
            ),
        ),
    ),
));
    