Create an API client class.

This should make it easier to make API calls from the frontends.

framework/core/src/Api/Client.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace Flarum\Api;
+
+use Flarum\Support\Actor;
+use Illuminate\Contracts\Container\Container;
+
+class Client
+{
+    protected $container;
+
+    protected $actor;
+
+    public function __construct(Container $container, Actor $actor)
+    {
+        $this->container = $container;
+        $this->actor = $actor;
+    }
+
+    /**
+     * Execute the given API action class, pass the input and return its response.
+     *
+     * @param string $actionClass
+     * @param array $input
+     * @return object
+     */
+    public function send($actionClass, array $input = [])
+    {
+        /** @var \Flarum\Api\Actions\JsonApiAction $action */
+        $action = $this->container->make($actionClass);
+
+        $response = $action->handle(new Request($input, $this->actor));
+
+        return json_decode($response->getBody());
+    }
+}