Implement own flash messages interface and class.

app/src/Bootstrap.php

@@ -26,6 +26,8 @@ use Psr\Log\LoggerInterface;
 use Slim\App;
 use Slim\Factory\AppFactory;
 use Slim\Psr7\Factory\ResponseFactory;
+use Slovocast\Infrastructure\Session\FlashMessages;
+use Slovocast\Infrastructure\Session\FlashMessagesInterface;
 use Slovocast\Middleware\SessionMiddleware;
 use Twig\Error\LoaderError;
 
@@ -128,8 +130,16 @@ class Bootstrap
                 $options = $container->get('config')->get('session');
                 return new PhpSession($options);
             },
+            'session' => function (ContainerInterface $container) {
+                return $container->get(SessionInterface::class);
+            },
+            FlashMessagesInterface::class => function (ContainerInterface $container) {
+                return new FlashMessages(
+                    $container->get(SessionInterface::class)
+                );
+            },
             'flash' => function (ContainerInterface $container) {
-                return $container->get(SessionInterface::class)->getFlash();
+                return $container->get(FlashMessagesInterface::class);
             },
             SessionMiddleware::class => function (ContainerInterface $container) {
                 return new SessionMiddleware(

app/src/Infrastructure/Api/Session/FlashMessagesInterface.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Slovocast\Infrastructure\Session;
+
+interface FlashMessagesInterface
+{
+    /**
+     * Add a message to the flash system
+     *
+     * @param string $level
+     * @param string $message
+     * @return void
+     */
+    public function add(string $level, string $message): void;
+
+    /**
+     * Returns an array of all the flash messages for the level provided, and
+     * clears the cache.
+     *
+     * @param string $level
+     * @return array<string>
+     */
+    public function get(string $level): array;
+
+    /**
+     * @return array<string, array<string>>
+     */
+    public function getAll(): array;
+
+    /**
+     * @param string|null
+     */
+    public function clear(?string $level = null): void;
+}

app/src/Infrastructure/Session/FlashMessages.php

@@ -0,0 +1,82 @@
+<?php
+
+namespace Slovocast\Infrastructure\Session;
+
+use Odan\Session\SessionInterface;
+
+class FlashMessages implements FlashMessagesInterface
+{
+    const LEVEL_ERROR = "error";
+    const LEVEL_NOTICE = "notice";
+    const LEVEL_SUCCESS = "success";
+
+    private string $key = "_flash";
+
+    public function __construct(
+        protected SessionInterface $session
+    ) {
+        if (!$this->session->has($this->key)) {
+            $this->session->set($this->key, []);
+        }
+    }
+
+    /**
+     * @return array<string, array<string>>
+     */
+    protected function getMessages(): array
+    {
+        return $this->session->get($this->key);
+    }
+
+    /**
+     * @param array<string, array<string>> $messages
+     * @return void
+     */
+    protected function saveMessages(array $messages): void
+    {
+        $this->session->set($this->key, $messages);
+    }
+    
+    public function add(string $level, string $message): void
+    {
+        $messages = $this->getMessages();
+        $messages[$level][] = $message;
+        $this->saveMessages($messages);
+    }
+
+    public function get(string $level): array
+    {
+        $messages = $this->getMessages();
+
+        if (!array_key_exists($level, $messages)) {
+            return [];
+        }
+
+        $buffer = $messages[$level];
+        unset($messages[$level]);
+        $this->saveMessages($messages);
+        return $buffer;
+    }
+
+    public function getAll(): array
+    {
+        $messages = $this->getMessages();
+        $this->clear();
+        return $messages;
+    }
+
+    public function clear(?string $level = null): void
+    {
+        if (!$level) {
+            $this->session->set($this->key, []);
+        } else {
+            $messages = $this->getMessages();
+
+            if (array_key_exists($level)) {
+                unset($messages[$level]);
+            }
+
+            $this->saveMessages($messages);
+        }
+    }
+}

app/src/Middlewares.php

@@ -10,6 +10,7 @@ use Psr\Container\NotFoundExceptionInterface;
 use Slim\App;
 use Slim\Views\Twig;
 use Slim\Views\TwigMiddleware;
+use Slovocast\Infrastructure\Session\FlashMessagesInterface;
 use Slovocast\Middleware\SessionMiddleware;
 use Twig\Error\LoaderError;
 
@@ -47,7 +48,7 @@ class Middlewares
         $twig->getEnvironment()->addGlobal('site_description', $config->get('site.description'));
 
         $session = $container->get(SessionInterface::class);
-        $flash = $session->getFlash();
+        $flash = $container->get(FlashMessagesInterface::class);
         $twig->getEnvironment()->addGlobal('session', $session);
         $twig->getEnvironment()->addGlobal('flash', $flash);