emails/api/setup/setups/98_log.php

<?php
use Psr\Container\ContainerInterface;

return [
    'log_processors' => function(ContainerInterface $container) {
        return [
            $container->get(Monolog\Processor\PsrLogMessageProcessor::class),
            $container->get(Monolog\Processor\IntrospectionProcessor::class),
            $container->get(Monolog\Processor\WebProcessor::class),
            $container->get(Monolog\Processor\MemoryPeakUsageProcessor::class),
        ];
    },
    'request_log_handler' => function(ContainerInterface $container) {
        return (new Monolog\Handler\RotatingFileHandler(implode(DIRECTORY_SEPARATOR, [$container->get('logs_folder'), 'requests.log'])));
    },
    'request_logger' => function(ContainerInterface $container) {
        return new Monolog\Logger(
            'request_logger',
            [$container->get('request_log_handler')],
            $container->get('log_processors')
        );
    },
    'file_log_handler' => function(ContainerInterface $container) {
        return new Monolog\Handler\FilterHandler(
            (new Monolog\Handler\RotatingFileHandler($container->get('log_file')))
                ->setFormatter(new Monolog\Formatter\LineFormatter(null, null, true)),
            Monolog\Level::Error
        );
    },
    'debug_log_handler' => function(ContainerInterface $container) {
        return new Monolog\Handler\FilterHandler(
            (new Monolog\Handler\RotatingFileHandler(implode(DIRECTORY_SEPARATOR, [$container->get('logs_folder'), 'debug.log'])))
                ->setFormatter(new Monolog\Formatter\LineFormatter(null, null, true)),
            Monolog\Level::Debug,
            Monolog\Level::Warning
        );
    },
    Psr\Log\LoggerInterface::class => function(ContainerInterface $container) {
        return $container->get('file_logger');
    },
    'file_logger' => function(ContainerInterface $container) {
        return new Monolog\Logger(
            'file',
            [
                $container->get('file_log_handler'),
                $container->get('debug_log_handler')
            ],
            $container->get('log_processors')
        );
    },
    'elk_logger' => function(ContainerInterface $container) {
        return new Monolog\Logger('elk', [
            (new Monolog\Handler\SocketHandler($container->get('logstash_socket')))
                ->setFormatter(new Monolog\Formatter\LogstashFormatter('emails', 'docker'))
        ], [
            new Monolog\Processor\PsrLogMessageProcessor(),
            new Monolog\Processor\WebProcessor(),
            new Monolog\Processor\IntrospectionProcessor(),
            new Monolog\Processor\MemoryPeakUsageProcessor()
        ]);
    }
];