Move floodgate to middleware, add extender + integration tests (#2170)

src/Extend/ThrottleApi.php

@@ -0,0 +1,74 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Extend;
+
+use Flarum\Extension\Extension;
+use Flarum\Foundation\ContainerUtil;
+use Illuminate\Contracts\Container\Container;
+
+class ThrottleApi implements ExtenderInterface
+{
+    private $setThrottlers = [];
+    private $removeThrottlers = [];
+
+    /**
+     * Add a new throttler (or override one with the same name).
+     *
+     * @param string $name: The name of the throttler.
+     * @param string|callable $callback
+     *
+     * The callable can be a closure or invokable class, and should accept:
+     *   - $request: The current `\Psr\Http\Message\ServerRequestInterface` request object.
+     *               `$request->getAttribute('actor')` can be used to get the current user.
+     *               `$request->getAttribute('routeName')` can be used to get the current route.
+     * Please note that every throttler runs by default on every route.
+     * If you only want to throttle certain routes, you'll need to check for that inside your logic.
+     *
+     * The callable should return one of:
+     *   - `false`: This marks the request as NOT to be throttled. It overrides all other throttlers
+     *   - `true`: This marks the request as to be throttled.
+     *  All other outputs will be ignored.
+     *
+     * @return self
+     */
+    public function set(string $name, $callback)
+    {
+        $this->setThrottlers[$name] = $callback;
+
+        return $this;
+    }
+
+    /**
+     * Remove a throttler registered with this name.
+     *
+     * @param string $name: The name of the throttler to remove.
+     *
+     * @return self
+     */
+    public function remove(string $name)
+    {
+        $this->removeThrottlers[] = $name;
+
+        return $this;
+    }
+
+    public function extend(Container $container, Extension $extension = null)
+    {
+        $container->extend('flarum.api.throttlers', function ($throttlers) use ($container) {
+            $throttlers = array_diff_key($throttlers, array_flip($this->removeThrottlers));
+
+            foreach ($this->setThrottlers as $name => $throttler) {
+                $throttlers[$name] = ContainerUtil::wrapCallback($throttler, $container);
+            }
+
+            return $throttlers;
+        });
+    }
+}