Use new method for retrieving base URL

admin.php

@@ -23,7 +23,7 @@ $admin = new MiddlewarePipe();
 $admin->pipe($app->make('Flarum\Api\Middleware\ReadJsonParameters'));
 $admin->pipe($app->make('Flarum\Admin\Middleware\LoginWithCookieAndCheckAdmin'));
 
-$adminPath = parse_url(Core::config('admin_url'), PHP_URL_PATH);
+$adminPath = parse_url(Core::url('admin'), PHP_URL_PATH);
 $router = $app->make('Flarum\Http\RouterMiddleware', ['routes' => $app->make('flarum.admin.routes')]);
 
 $admin->pipe($adminPath, $router);

api.php

@@ -23,7 +23,7 @@ $api = new MiddlewarePipe();
 $api->pipe($app->make('Flarum\Api\Middleware\ReadJsonParameters'));
 $api->pipe($app->make('Flarum\Api\Middleware\LoginWithHeader'));
 
-$apiPath = parse_url(Core::config('api_url'), PHP_URL_PATH);
+$apiPath = parse_url(Core::url('api'), PHP_URL_PATH);
 $router = $app->make('Flarum\Http\RouterMiddleware', ['routes' => $app->make('flarum.api.routes')]);
 
 $api->pipe($apiPath, $router);

index.php

@@ -27,7 +27,7 @@ if ($app->bound('flarum.config')) {
     $flarum->pipe($app->make('Flarum\Forum\Middleware\LoginWithCookie'));
     $flarum->pipe($app->make('Flarum\Api\Middleware\ReadJsonParameters'));
 
-    $basePath = parse_url(Core::config('base_url'), PHP_URL_PATH);
+    $basePath = parse_url(Core::url(), PHP_URL_PATH);
     $router = $app->make('Flarum\Http\RouterMiddleware', ['routes' => $app->make('flarum.forum.routes')]);
 
     $flarum->pipe($basePath, $router);