How to log Messages to different Files

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Switching a Channel to a different Handler
YAML specification
Creating your own Channel
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How to log Messages to different Files

2.1

The ability to specify channels for a specific handler was added to the MonologBundle for Symfony 2.1.

The Symfony Standard Edition contains a bunch of channels for logging: doctrine, event, security and request. Each channel corresponds to a logger service (monolog.logger.XXX) in the container and is injected to the concerned service. The purpose of channels is to be able to organize different types of log messages.

By default, Symfony2 logs every messages into a single file (regardless of the channel).

Switching a Channel to a different Handler

Now, suppose you want to log the doctrine channel to a different file.

To do so, just create a new handler and configure it like this:

YAML
XML
PHP

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        # app/config/config.yml
monolog:
    handlers:
        main:
            type:     stream
            path:     /var/log/symfony.log
            channels: [!doctrine]
        doctrine:
            type:     stream
            path:     /var/log/doctrine.log
            channels: [doctrine]
    

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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 name="main" type="stream" path="/var/log/symfony.log">
            <monolog:channels>
                <monolog:channel>!doctrine</monolog:channel>
            </monolog:channels>
        </monolog:handler>

        <monolog:handler name="doctrine" type="stream" path="/var/log/doctrine.log">
            <monolog:channels>
                <monolog:channel>doctrine</monolog:channel>
            </monolog:channels>
        </monolog:handler>
    </monolog:config>
</container>
    

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        // app/config/config.php
$container->loadFromExtension('monolog', array(
    'handlers' => array(
        'main'     => array(
            'type'     => 'stream',
            'path'     => '/var/log/symfony.log',
            'channels' => array(
                '!doctrine',
            ),
        ),
        'doctrine' => array(
            'type'     => 'stream',
            'path'     => '/var/log/doctrine.log',
            'channels' => array(
                'doctrine',
            ),
        ),
    ),
));
    

YAML specification

You can specify the configuration by many forms:

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        channels: ~    # Include all the channels

channels: foo  # Include only channel "foo"
channels: !foo # Include all channels, except "foo"

channels: [foo, bar]   # Include only channels "foo" and "bar"
channels: [!foo, !bar] # Include all channels, except "foo" and "bar"
    

Creating your own Channel

You can change the channel monolog logs to one service at a time. This is done by tagging your service with monolog.logger and specifying which channel the service should log to. By doing this, the logger that is injected into that service is preconfigured to use the channel you've specified.

For more information - including a full example - read "The Dependency Injection Tags" in the Dependency Injection Tags reference section.