a simple (:effort:) key value store

index.php

<?php

require_once 'Store.php';

// might want to change this so the db file is not in your webroot.  Like:
// $store = new Store(new PDO('sqlite:' . dirname(__FILE__) . '/../data.db'));
$store = new Store(new PDO('sqlite:data.db'));

$store->createTable();

if (isset($_GET['key']))
{
	$data = $store->get($_GET['key']);

	if (!empty($data))
	{
		echo $data['value'];
	}
	else
	{
		header('', true, 404);
		echo '404 - Not Found';
	}
}
else if (isset($_POST['key']) && isset($_POST['value']))
{
	$store->put($_POST['key'], $_POST['value']);
	echo 'OK';
}
else
{
	header('', true, 400);
	echo '400 - Bad Request';
}

Store.php

<?php

class Store
{
	public function __construct(\PDO $db)
	{
		$this->db = $db;
		$this->db->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
	}

	public function createTable()
	{
		$this->db->exec('CREATE TABLE IF NOT EXISTS `data` (`key` TEXT PRIMARY KEY, `value` TEXT);');
	}

	/**
	 *
	 * Create or update an existing key-value pair
	 *
	 * @param $key
	 * @param $value
	 *
	 * @return bool
	 */
	public function put($key, $value)
	{
		$stmt = $this->db->prepare('INSERT OR REPLACE INTO `data` (`key`, `value`) VALUES (?, ?)');

		return $stmt->execute([$key, $value]);
	}

	/**
	 *
	 * Get an existing key-value pair
	 *
	 * @param $key
	 *
	 * @return array
	 */
	public function get($key)
	{
		$stmt = $this->db->prepare('SELECT * FROM `data` WHERE `key` = ?');
		$stmt->execute([$key]);

		return $stmt->fetch(\PDO::FETCH_ASSOC);
	}
}