How to Define a Custom Logging Formatter
========================================

Each logging handler uses a ``Formatter`` to format the record before logging
it. All Monolog handlers use an instance of
``Monolog\Formatter\LineFormatter`` by default but you can replace it.
Your formatter must implement ``Monolog\Formatter\FormatterInterface``.

For example, to use the built-in ``JsonFormatter``, register it as a service then
configure your handler to use it:

.. configuration-block::

    .. code-block:: yaml

        # config/packages/prod/monolog.yaml (and/or config/packages/dev/monolog.yaml)
        monolog:
            handlers:
                file:
                    type: stream
                    level: debug
                    formatter: 'monolog.formatter.json'

    .. code-block:: xml

        <!-- config/services.xml -->
        <?xml version="1.0" encoding="UTF-8" ?>
        <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
                https://symfony.com/schema/dic/services/services-1.0.xsd
                http://symfony.com/schema/dic/monolog
                https://symfony.com/schema/dic/monolog/monolog-1.0.xsd">

            <!-- config/packages/prod/monolog.xml (and/or config/packages/dev/monolog.xml) -->
            <monolog:config>
                <monolog:handler
                    name="file"
                    type="stream"
                    level="debug"
                    formatter="monolog.formatter.json"
                />
            </monolog:config>
        </container>

    .. code-block:: php

        // config/services.php
        use Monolog\Formatter\JsonFormatter;

        // config/packages/prod/monolog.php (and/or config/packages/dev/monolog.php)
        $container->loadFromExtension('monolog', [
            'handlers' => [
                'file' => [
                    'type'      => 'stream',
                    'level'     => 'debug',
                    'formatter' => 'monolog.formatter.json',
                ],
            ],
        ]);