05-logging.md

Logging

Configure and use logging with PDOdb.

Setup Logger

use Monolog\Logger;
use Monolog\Handler\StreamHandler;

$logger = new Logger('database');
$logger->pushHandler(new StreamHandler('php://stdout'));

$db = new PdoDb('mysql', [
    'host' => 'localhost',
    'dbname' => 'test'
], [], $logger);

Query Logging

Enable Query Log

$db->enableQueryLog();

// Execute queries
$users = $db->find()->from('users')->get();
$orders = $db->find()->from('orders')->get();

// Get log
$log = $db->getQueryLog();

foreach ($log as $entry) {
    echo $entry['sql'] . "\n";
    echo "Time: " . $entry['time'] . "ms\n";
}

Disable Query Log

$db->disableQueryLog();

Log Levels

Connection Log

// Logs connection attempts and failures
$logger->info('Connecting to database', [
    'host' => 'localhost',
    'database' => 'mydb'
]);

Query Log

// Logs executed queries
$logger->debug('Executing query', [
    'sql' => $sql,
    'params' => $params,
    'time' => $executionTime
]);

Error Log

try {
    $users = $db->find()->from('users')->get();
} catch (QueryException $e) {
    $logger->error('Query failed', [
        'error' => $e->getMessage(),
        'code' => $e->getCode()
    ]);
}

Custom Log Handler

use Monolog\Handler\AbstractHandler;

class DatabaseHandler extends AbstractHandler {
    public function handle(array $record): bool {
        // Save to database
        // ...
        return true;
    }
}

$handler = new DatabaseHandler();
$logger->pushHandler($handler);

Next Steps

• Exception Hierarchy - Exception types
• Monitoring - Error tracking
• Retry Logic - Build retry logic