Add MariaDB container; add PDO connection; add error middleware

src/Dependencies.php

@@ -5,14 +5,16 @@ namespace MailAccountAdmin;
 
 use DI\Container;
 use MailAccountAdmin\Login\LoginController;
+use PDO;
 use Psr\Container\ContainerInterface;
 use Slim\Views\Twig;
 
 class Dependencies
 {
-    private const SETTINGS = 'settings';
-    private const TWIG = 'view';
+    public const SETTINGS = 'settings';
+    public const TWIG = 'view';
     private const TWIG_TEMPLATE_DIR = __DIR__ . '/../templates';
+    public const DATABASE = 'database';
 
     public static function createContainer(Settings $settings): Container
     {
@@ -29,6 +31,22 @@ class Dependencies
             return Twig::create(self::TWIG_TEMPLATE_DIR, $settings->getTwigSettings());
         });
 
+        // Database connection
+        $container->set(self::DATABASE, function (ContainerInterface $c) {
+            /** @var Settings $settings */
+            $settings = $c->get(self::SETTINGS);
+            $dbSettings = $settings->getDatabaseSettings();
+
+            return new PDO(
+                "mysql:dbname={$dbSettings['dbname']};host={$dbSettings['host']};port={$dbSettings['port']}",
+                $dbSettings['username'],
+                $dbSettings['password'],
+                [
+                    PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
+                ],
+            );
+        });
+
         // Login, registration, authentication
         $container->set(LoginController::class, function (ContainerInterface $c) {
             return new LoginController(