Custom log file not creating

Question

I am using Magento 2.4.0 and trying to put a custom log for my custom module by extending the \Monolog\Logger but the log file is not created in the Magentoroot/var/log path. I have attached all the code snippets for your reference, anybody who can help please leave a comment.

Diligent - is my vendor or namespace CoveoLog - is my module

Handler.php file

<?php
namespace Diligent\CoveoLog\Logger;

use Monolog\Logger;

class Handler extends \Magento\Framework\Logger\Handler\Base
{
    protected $loggerType = Logger::INFO;

    protected $fileName = '/var/log/Diligent.log';
}

Logger.php

<?php
namespace Diligent\CoveoLog\Logger;

class Logger extends \Monolog\Logger
{
}

Model.php

<?php
namespace Diligent\CoveoLog\Model;

class MyModel
{
    protected $_logger;

    public function __construct(
        \Diligent\CoveoLog\Logger\Logger $logger
    ) {
        $this->_logger = $logger;
    }

    public function doSomething()
    {
        $this->_logger->info('Hello');
    }
}

di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../lib/internal/Magento/Framework/ObjectManager/etc/config.xsd">
    <type name="Diligent\CoveoLog\Logger\Handler">
        <arguments>
            <argument name="filesystem" xsi:type="object">Magento\Framework\Filesystem\Driver\File</argument>
        </arguments>
    </type>
    <type name="Diligent\CoveoLog\Logger\Logger">
        <arguments>
            <argument name="name" xsi:type="string">CoveoLog</argument>
            <argument name="handlers" xsi:type="array">
                <item name="system" xsi:type="object">Diligent\CoveoLog\Logger\Handler</item>
            </argument>
        </arguments>
    </type>
</config>

module.xml

<?xml version="1.0" encoding="UTF-8"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Module/etc/module.xsd">
   <module name="Diligent_CoveoLog" setup_version="1.0.0" schema_version="1.0.0" />
</config>

registration.php

<?php 
\Magento\Framework\Component\ComponentRegistrar::register(
  \Magento\Framework\Component\ComponentRegistrar::MODULE, 
        'Diligent_CoveoLog',
__DIR__
);

Note: I have tried by clearing cache and doing reindex.

Answer 1

I can't see any problems with your code I used the following:

di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <!-- Logger Configuration -->
    <type name="Vendor\Module\Logger\Handler">
        <arguments>
            <argument name="filesystem" xsi:type="object">Magento\Framework\Filesystem\Driver\File</argument>
        </arguments>
    </type>
    <type name="Vendor\Module\Logger\Logger">
        <arguments>
            <argument name="name" xsi:type="string">customLogger</argument>
            <argument name="handlers"  xsi:type="array">
                <item name="system" xsi:type="object">Vendor\Module\Logger\Handler</item>
            </argument>
        </arguments>
    </type>
</config>

Logger.php

<?php

namespace Vendor\Module\Logger;

class Logger extends \Monolog\Logger
{


}

Handler.php

<?php
namespace Vendor\Module\Logger;

class Handler extends \Magento\Framework\Logger\Handler\Base
{

   /**
     * Logging level
     * @var int
     */
    protected $loggerType = Logger::INFO;

    /**
     * File name
     * @var string
     */
    protected $fileName = '/var/log/customlog.log';

}

MyClass.php

private $logger;

public function __construct(
    \Vendor\Module\Logger\Logger $logger
) {

    $this->logger = $logger;
}

When I use

$this->logger->info('This is a test...');

I see the log generated in var/log/customlog.log

[2021-02-25 12:33:59] customLogger.INFO: This is a test... [] []

Note: if your Class is extending another class where $logger is declared, overwrite it with your custom logger after the parent constructor:

public function __construct(
    \Vendor\Module\Logger\Logger $logger,
    AppState $appState
) {
    $this->appState = $appState;

    parent::__construct();

    $this->logger = $logger;
}