• Robust exception and error management
• Handling file transmissions (uploads/downloads)
• Dynamic media manipulation (e.g., GD library)
• Persistent data storage via PDO or MySQLi
• Debugging strategies and unit testing
• Object-Oriented paradigms (OOP)
• Namespace organization
• Dependency management with Composer and PSR standards
• Non-blocking execution (ReactPHP, Swoole)
• Security hardening (XSS mitigation, cryptographic hashing)

Below are practical implementations demonstrating file handling, image manipulation, database operations, and HTTP requests.

// Handling File Transmission
if (isset($_FILES['document']) && $_FILES['document']['error'] === UPLOAD_ERR_OK) {
    $tempPath = $_FILES['document']['tmp_name'];
    $originalName = basename($_FILES['document']['name']);
    $destination = '/var/www/uploads/' . $originalName;

    if (move_uploaded_file($tempPath, $destination)) {
        // File successfully moved
    }
}

// Image Manipulation using GD
$sourceImage = imagecreatefromjpeg($destination);
$width = imagesx($sourceImage);
$height = imagesy($sourceImage);
$newImage = imagecreatetruecolor($width, $height);
imagecopyresampled($newImage, $sourceImage, 0, 0, 0, 0, $width, $height, $width, $height);
imagejpeg($newImage, '/var/www/processed/resized_' . $originalName, 90);
imagedestroy($sourceImage);
imagedestroy($newImage);

// Database Operation using PDO
try {
    $dbConnection = new PDO('mysql:host=127.0.0.1;dbname=app_db', 'db_user', 'secure_pass');
    $dbConnection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    $insertQuery = "INSERT INTO accounts (handle, contact_email) VALUES (:handle, :email)";
    $statement = $dbConnection->prepare($insertQuery);
    $statement->execute([':handle' => $handle, ':email' => $email]);
} catch (PDOException $ex) {
    // Handle database exception
}

// Executing HTTP GET Request
function fetchRemoteData($apiEndpoint, $queryParams = []) {
    if (!empty($queryParams)) {
        $apiEndpoint .= '?' . http_build_query($queryParams);
    }

    $curlHandler = curl_init();
    $options = [
        CURLOPT_URL            => $apiEndpoint,
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_HEADER         => false,
        CURLOPT_TIMEOUT        => 30,
    ];
    curl_setopt_array($curlHandler, $options);

    $responsePayload = curl_exec($curlHandler);

    if ($responsePayload === false) {
        $failureReason = curl_error($curlHandler);
        curl_close($curlHandler);
        throw new RuntimeException("HTTP request failed: " . $failureReason);
    }

    curl_close($curlHandler);
    return $responsePayload;
}