PHP Behat / mink + selenium2 webdriver意外启动新的实例/会话

Question

我试图帮助朋友使用behat/mink + selenium2自动执行某个流程。它正在工作，但不知何故在进程的中间，selenium2启动与原始并行运行的新实例/会话。

有没有办法防止此行为并且只保留一个实例/会话？

这是我的代码（laravel控制器类）：

class testBehat extends Controller
{
    protected $session;
    public function __construct()
    {
        set_time_limit(300);
        $driver = new Selenium2Driver('firefox');
        $capabilities = $driver->getDefaultCapabilities();
        $driver->setWebDriver(new WebDriver('http://10.99.0.11:5555/wd/hub'));
        $this->session = new Session($driver);
    }

    public function run()
    {
        $admin = User::find(0);
        $simulator = Simulator::find(0);
        $this->session->start();
        $this->login($admin->username, $admin->pass);
        if ($this->isElementExist('id', 'profilemenu')) {
            $this->session->visit('http://dar*******.com/simulator/new/');
        }
        $this->upload($simulator);
        file_put_contents(public_path('screenshoot/' . $admin->user . '-' . $simulator->name . '-success.jpg'), $this->session->getScreenshot());

        $this->session->stop();
        return 'success';
    }

    private function login($user, $pass)
    {
        $this->session->visit('http://dar*******.com/signin');
        $this->handlePages('id', 'username', 'text', $user);
        $this->handlePages('id', 'password', 'text', $pass);
        $this->handlePages('id', 'submit', 'click');
        file_put_contents(public_path('screenshoot/' . $user . '-' . '-loggedin.jpg'), $this->session->getScreenshot());
    }

    private function isElementExist($selector, $locator)
    {
        if ($selector === 'css')
        {
            while (!$this->session->getPage()->has($selector, $locator)) {
                sleep(1);
                file_put_contents(public_path('public/element.jpg'), $this->session->getScreenshot());
            }
            $return = true;
        }
        elseif ($selector === 'id' || $selector === 'name')
        {
            if ($locator === 'tags') {
                $selector = 'id_or_name';
            }

            while (!$this->session->getPage()->has('named', array($selector, $locator))) {
                sleep(1);
                file_put_contents(public_path('screenshoot/element.jpg'), $this->session->getScreenshot());
            }
            $return = true;
        }

        return $return;

    }

    public function handlePages($selector, $locator, $action, $data = null)
    {
        $element = $this->elementFinder($selector, $locator);
        switch ($action) {
            case 'text':
                $element->setValue($data);
                break;
            case 'file':
                $element->attachFile($data);
                break;
            case 'select':
                $element->selectOption($data);
                break;
            case 'click':
                $element->click();
                break;
            case 'load':

                break;
            case 'upload':
                while ($element->getAttribute('style') !== 'width: 100%;') {
                    sleep(1);
                }
                break;
            default:
                echo 'Action not found.';
                exit;
        }
        return $element;
    }

    public function elementFinder($selector, $locator)
    {
        if ($this->isElementExist($selector, $locator)) {
            if ($selector === 'css') {
                return $this->session->getPage()->find('css', $locator);
        } else {
            if ($locator === 'tags') {
                $selector = 'id_or_name';
            }

            return $this->session->getPage()->find('named', array($selector, $locator));
        }
        } else {
            echo 'Element not Found.';
        }
        return null;
    }

    private function upload($simulator)
    {
        $this->handlePages('id', 'fileupload', 'file', '~/simulator/'. $simulator->name);
        sleep(4);
        file_put_contents(public_path('screenshoot/' . $simulator->name . '-simulator-file.jpg'), $this->session->getScreenshot());

        $this->handlePages('id', 'sim_name', 'text', $simulator->name);
        file_put_contents(public_path('screenshoot/' . $simulator->name . '-name-field.jpg'), $this->session->getScreenshot());
        $this->handlePages('id', 'sim_category', 'select', $simulator->category);
        $this->handlePages('id', 'sim_remark', 'text', $simulator->remark));

        $this->handlePages('id', 'save', 'click');
    }
}

我在网格模式下运行selenium服务器，集线器和节点通过内部网络（LAN）连接。这是我用来启动selenium服务器的命令（我将jar文件重命名为selenium-server.jar）：

root@10.99.0.10:~/selenium2# java -jar selenium-server.jar -role hub -timeout 12000 -browserTimeout 12000 

root@10.99.0.11:~/selenium2# java -jar selenium-server.jar -role node -host 10.99.0.11 -hub http://10.99.0.10:4444/grid/register/ -timeout 12000 -browserTimeout 12000

我使用laravel 5.1，behat / mink，behat / mink-selenium2-driver和selenium standalone 2.48.2

这是我的问题，在第一次/原始会话运行时，selenium2意外启动了新会话。

Original session starting

Unexpectedly started another session while the original running

如何告诉selenium2服务器一次只启动/运行1个会话？

谢谢。