* kanban service and stuff

src/App/Handler/AvatarHandler.php

@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Handler;
+
+use App\Service\AvatarService;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+use Zend\Diactoros\Response\TextResponse;
+
+class AvatarHandler implements RequestHandlerInterface
+{
+    /** @var AvatarService  */
+    private $avatarService;
+
+    /**
+     * AvatarHandler constructor.
+     * @param AvatarService $avatarService
+     */
+    public function __construct(AvatarService $avatarService)
+    {
+        $this->avatarService = $avatarService;
+    }
+
+    /**
+     * @param ServerRequestInterface $request
+     * @return ResponseInterface
+     */
+    public function handle(ServerRequestInterface $request): ResponseInterface
+    {
+        $signum = $request->getAttribute('signum', false);
+        try {
+            $avatarImageData = $this->avatarService->getAvatarImageData($signum);
+        } catch (\UnexpectedValueException $e) {
+            return new TextResponse("Avatar not found", 404);
+        }
+        return (new TextResponse($avatarImageData, 200, [
+            'content-type' => 'image/png',
+        ]))->withHeader('Expires', '0')
+            ->withHeader('Cache-Control', 'must-revalidate');
+    }
+}