Flarum\Api\Controller\SetPermissionController::handle PHP Method

    public function handle(ServerRequestInterface $request)
    {
        $this->assertAdmin($request->getAttribute('actor'));
        $body = $request->getParsedBody();
        $permission = array_get($body, 'permission');
        $groupIds = array_get($body, 'groupIds');
        Permission::where('permission', $permission)->delete();
        Permission::insert(array_map(function ($groupId) use($permission) {
            return ['permission' => $permission, 'group_id' => $groupId];
        }, $groupIds));
        return new EmptyResponse(204);
    }