channels_handlers.rst

.. index::
   single: Logging

How to log Messages to different Files

.. versionadded:: 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:

.. configuration-block::

    .. code-block:: yaml

        monolog:
            handlers:
                main:
                    type: stream
                    path: /var/log/symfony.log
                    channels: !doctrine
                doctrine:
                    type: stream
                    path: /var/log/doctrine.log
                    channels: doctrine

    .. code-block:: xml

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

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

Yaml specification

You can specify the configuration by many forms:

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"

channels:
    type:     inclusive # Include only those listed below
    elements: [ foo, bar ]
channels:
    type:     exclusive # Include all, except those listed below
    elements: [ foo, bar ]

Learn more from the Cookbook

• :doc:`/cookbook/logging/monolog`