Using Aura\SQL to Log Slow Queries via a simple Decorator Class

bootstrap.php

<?php
declare(strict_types=1);

use Aura\Sql\{DecoratedPdo, Profiler\Profiler}
use Monolog\{Level, Logger, Handler\StreamHandler};
use YourProject\Infrastructure\Logging\SlowQueryLogDecorator;

$connection = get_connection_details_from_somewhere();

//create the base logger, then wrap it with the decorator
$baseLogger = new Logger('selective-logging-based-on-query-time');
$baseLogger->pushHandler(new StreamHandler('path/to/log/file.log', Level::Info));
$decorator = new SlowQueryLogDecorator($baseLogger);

//create the base PDO object and then wrap it with the Aura\SQL decorator
$originalPdo = new PDO(...$connection);
$pdo = new DecoratedPdo($originalPdo);

//create the profiler with the slow query log decorator and then set it with the Aura\SQL decorator
$profiler = new Profiler($decorator);
$pdo->setProfiler($profiler);

return $pdo;

SlowQueryLogDecorator.php

<?php
declare(strict_types=1);

namespace YourApp\Infrastructure\Logging;

use Psr\Log\{LoggerInterface, LoggerTrait};

class SlowQueryLogDecorator implements LoggerInterface
{
    use LoggerTrait;

    /**
     * @var int Minimum execution time before queries should be logged in milliseconds
     */
    private int $querySpeedThreshold;

    private LoggerInterface $next;

    public function __construct(LoggerInterface $next, int $querySpeedThreshold = 5000)
    {
        $this->next = $next;
        $this->querySpeedThreshold = $querySpeedThreshold;
    }

    /**
     * Logs with an arbitrary level.
     *
     * @param mixed   $level
     * @param string  $message
     * @param mixed[] $context
     *
     * @return void
     *
     * @throws \Psr\Log\InvalidArgumentException
     */
    public function log($level, $message, array $context = [])
    {
        if ($this->shouldLog($context)) {
            $this->next->log($level, $message, $context);
        }
    }

    /**
     * Checks to see whether this query should be logged based on its duration
     *
     * @param $context array{duration: numeric, ...}
     * @return bool
     */
    private function shouldLog(array $context): bool
    {
        if (!array_key_exists('duration', $context)) {
            return false;
        }
        return $context['duration'] >= (float) $this->querySpeedThreshold;
    }
}