Logging

Logging helps you track application behavior, diagnose bugs, and analyze performance by recording events, context, and errors to various destinations without impacting functionality.

Features

• Adapter Pattern: Send logs to multiple destinations (files, console, etc.) simultaneously.
• Factory Pattern: Easily configure and initialize the logger via an array.
• Standard Levels: Supports all RFC 5424 logging levels.
• Context Support: Pass contextual data arrays with log messages.

Usage

1. Basic Setup (Manual)

<?php

use Krystal\Logging\Logger;
use Krystal\Logging\Adapter\FileWriter;
use Krystal\Logging\Adapter\ConsoleWriter;

// Create the logger instance
$logger = new Logger();

// Add writers (adapters)
$logger->addWriter(new FileWriter(__DIR__ . '/app.log'));
$logger->addWriter(new ConsoleWriter());

// Log messages
$logger->info('Application started');
$logger->error('Database connection failed', ['host' => 'localhost', 'port' => 3306]);

2. Setup via Factory

The LoggerFactory allows you to define configuration in an array, making it easy to integrate with configuration files.

<?php

use Krystal\Logging\LoggerFactory;

$logger = LoggerFactory::build([
    'writers' => [
        [
            'type' => 'file',
            'path' => __DIR__ . '/app.log'
        ],
        [
            'type' => 'console'
        ]
    ]
]);

// Log messages
$logger->warning('This is a warning message');

3. Using as a Component

The logger is automatically available in controllers, module files, when configured in the main configuration file.

Step 1 – Configuration (config/app.php)

Define the logger in your main application configuration file.

<?php

return [
    'components' => [
        'logger' => [
            'writers' => [
                [
                    'type' => 'file',
                    'path' => dirname(__DIR__) . '/data/logs/app-' . date('Y-m-d') . '.log',
                ],
                [
                    'type'  => 'console'
                ]
            ]
        ],
        // other components...
    ]
];

Tip: In real production setups, move the date('Y-m-d') logic to a bootstrap file or environment variable so you can override it later.

Step 2 – Usage in Controllers

Then use it in controllers like this

public function addAction()
{
    $this->logger->warning('This is a warning message');
}

Logging Levels

The library supports the following levels (ordered from highest to lowest severity):

Method	Level	Description
$logger->emergency()	0	System is unusable.
$logger->alert()	1	Action must be taken immediately.
$logger->critical()	2	Critical conditions.
$logger->error()	3	Runtime errors.
$logger->warning()	4	Exceptional occurrences that are not errors.
$logger->notice()	5	Normal but significant events.
$logger->info()	6	Interesting events.
$logger->debug()	7	Detailed debug information.

Creating Custom Adapters

To create a new adapter, implement the Krystal\Logging\Adapter\LogWriterInterface.

<?php

use Krystal\Logging\Adapter\LogWriterInterface;

class SlackWriter implements LogWriterInterface
{
    public function write(int $level, string $message, array $context = []): bool
    {
        // Custom logic to send message to Slack
        return true;
    }
}

Then add manually add it:

$logger->addWriter(new SlackWriter());