PHP7 Chain Of Responsibilities

Behavioral/ChainOfResponsibilities/Responsible/SlowDatabaseHandler.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace DesignPatterns\Behavioral\ChainOfResponsibilities\Responsible;
+
+use DesignPatterns\Behavioral\ChainOfResponsibilities\Handler;
+use Psr\Http\Message\RequestInterface;
+
+class SlowDatabaseHandler extends Handler
+{
+    /**
+     * @param RequestInterface $request
+     *
+     * @return string|null
+     */
+    protected function processing(RequestInterface $request)
+    {
+        // this is a mockup, in production code you would ask a slow (compared to in-memory) DB for the results
+
+        return 'Hello World!';
+    }
+}