使用CSRF和Captcha在Symfony中测试Ajax调用

Question

I render a form from the following controller method:

  public function indexAction(Request $request)
    {

        $session=$this->get('session');
        $builder = $this->get('app.captcha');
        $builder->build();
        $session->set('registration_step2',$builder->getPhrase());

        return $this->render('pages/registration.html.twig',[
          'image'=>$this->createCaptcha('registration_step2')
        ])
   }

The form I render is pages/registration.html.twig:

<form id="contactForm" class="col-12" data-scroll-to="displayRegistationPaperApplicationWrapper" action="{{ path('registration_email_contact') }}" method="post">
       <input type="hidden" name="csrf" value="{{ csrf_token('insert-email') }}"/>

         <div class="col-12 mb-3">
           <div class="col-12">
             <div class="input-group">
                <div class="input-group-prepend">
                  <button class="btn btn-secondary" data-autofill-to="autofill_email" data-autofill-from="registrationEmail" id="emailAutofill">{{ 'register.step2.email.autofill'|trans }}</button>
                </div>
                <input id="autofill_email" type="email"  name="autofill_email" class="form-control" placeholder="{{ 'register.step2.email'|trans }}" required/>
              </div>
           </div>
         </div>
        <div class="col-12">
           <div class="col-2 float-left border">
             <img id="capthaImage" class="img-fluid" data-captha-renew="registration_step2" src="{{ image }}">
           </div>
           <div class="col-10 float-right">
             <div class="input-group">
                <div class="input-group-prepend">
                  <button class="btn btn-secondary" id="reset-captcha">{{ 'register.captha.new-image'|trans }}</button>
                </div>
                <input type="text" name="captcha" class="form-control" placeholder="{{ 'register.captcha'|trans }}" required/>
              </div>
           </div>
         </div>
         <div class="col-12 mt-5 mb-2">
           <div class="col-12 col-sm-12 col-md-5 col-lg-5 ml-auto">
            <div class="btn-group" role="group" aria-label="Basic example">
              <button id="rejectEmail" data-scroll-to="displayRegistationPaperApplicationWrapper" type="button" class="btn btn-link text-danger">{{ 'register.step2.no'|trans }}</button>
              <button type="submit" class="btn btn-success">{{ 'register.step2.yes'|trans }}</button>
            </div>
          </div>
         </div>
    </form>

The form will be submited via Ajax (I do not place javascript code in order to keep the question as small as possible) using a seperate controller method. For example:

public function submitFormAction(Request $request)
{
  // Implement sumbit code here
}

What I want to test first via a phpunit functional test is the normal behavior of ajax Submission but how I will get: * The current csrf token * Captha string

WITHOUT needing to render completely the page where the csrf token and captcha is placed (because it is part of a multiple form).

For captcha I use gregwar's implementation and I define it as a service via:

app.captcha:
  class: 'Gregwar\Captcha\CaptchaBuilder'
  public: true

(I do not use the Bundle because I find it incovenient in my case where I use Ajax. I plan to make my own Service in a immediate refactor.)