Add a serializer and API action to get information about the forum

src/Api/Actions/Forum/ShowAction.php

@@ -0,0 +1,29 @@
+<?php namespace Flarum\Api\Actions\Forum;
+
+use Flarum\Core\Models\Forum;
+use Flarum\Api\Actions\SerializeResourceAction;
+use Flarum\Api\JsonApiRequest;
+use Flarum\Api\JsonApiResponse;
+
+class ShowAction extends SerializeResourceAction
+{
+    /**
+     * The name of the serializer class to output results with.
+     *
+     * @var string
+     */
+    public static $serializer = 'Flarum\Api\Serializers\ForumSerializer';
+
+    /**
+     * Get the forum, ready to be serialized and assigned to the JsonApi
+     * response.
+     *
+     * @param \Flarum\Api\JsonApiRequest $request
+     * @param \Flarum\Api\JsonApiResponse $response
+     * @return \Flarum\Core\Models\Forum
+     */
+    protected function data(JsonApiRequest $request, JsonApiResponse $response)
+    {
+        return app('flarum.forum');
+    }
+}