Multilevel dynamic forms in Symfony - symfony

Question

I need to create a form adding faculty to the database. First, the user selects a region from the list ( / ChoiceType), then the city of this region from the following list, the university, and finally enters the name of the faculty. The default values are the first region from the database, its first city and first university.
Sending the page with default data works, the choice of the region works, but the the choice of the city return to 500 status
Form:
Twig and ajax:
{% extends 'admin/insert/insert.html.twig' %}
{% block title %}Add Faculty{% endblock %}
{% block body %}
<div class="insert">
<h1 class="insert__title">Add Faculty</h1>
{{ form_start(insert_faculty, { 'attr' : {'class' : 'insert__form'} }) }}
{% for message in app.flashes('success') %}
<div class="insert__success">
{{ message }}
</div>
{% endfor %}
<div class="insert__errors">
{{ form_errors(insert_faculty) }}
</div>
{{ form_label(insert_faculty.region, 'Region:', { 'label_attr' : {'class' : 'insert__label'} }) }}
{{ form_widget(insert_faculty.region, { 'attr' : {'class' : 'insert__input'} }) }}
{{ form_label(insert_faculty.city, 'City:', { 'label_attr' : {'class' : 'insert__label'} }) }}
{{ form_widget(insert_faculty.city, { 'attr' : {'class' : 'insert__input'} }) }}
{{ form_label(insert_faculty.university, 'University:', { 'label_attr' : {'class' : 'insert__label'} }) }}
{{ form_widget(insert_faculty.university, { 'attr' : {'class' : 'insert__input'} }) }}
{{ form_label(insert_faculty.name, 'Name:', { 'label_attr' : {'class' : 'insert__label'} }) }}
{{ form_widget(insert_faculty.name, { 'attr' : {'class' : 'insert__input insert__input_name'} }) }}
<button type="submit" class="insert__button">Save</button>
{{ form_end(insert_faculty) }}
<div class="insert__buttons">
Back
</div>
</div>
{% block javascripts_footer %}
{{ parent() }}
<script>
let $region = $('#insert_faculty_region');
$region.change(function() {
let $form = $(this).closest('form');
let data = {};
data[$region.attr('name')] = $region.val();
$.ajax({
url : $form.attr('action'),
type: $form.attr('method'),
data : data,
success: function(get) {
$('#insert_faculty_city').html(
$(get).find('#insert_faculty_city').html()
);
$('#insert_faculty_university').html(
$(get).find('#insert_faculty_university').html()
);
}
});
});
let $city = $('#insert_faculty_city');
$city.change(function() {
let $form = $(this).closest('form');
let data = {};
data[$city.attr('name')] = $city.val();
$.ajax({
url : $form.attr('action'),
type: $form.attr('method'),
data : data,
success: function(get) {
$('#insert_faculty_university').html(
$(get).find('#insert_faculty_university').html()
);
}
});
});
</script>
{% endblock %}
{% endblock %}
Form class:
class InsertFacultyType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('region', ChoiceType::class, [
'choices' => $options['regions_array'],
'mapped' => false,
])
->add('city', ChoiceType::class, [
'choices' => null,
'mapped' => false,
])
->add('university', ChoiceType::class, [
'choices' => null,
])
->add('name')
;
$formModifier = function (FormInterface $form, $entity_parent) {
if (get_class($entity_parent) === 'App\Entity\Region') {
if (!$entity_parent->getCities()->count()) {
$form->add('city', ChoiceType::class, [
'choices' => null,
'mapped' => false,
]);
}
else {
$cities_in_database = $entity_parent->getCities();
foreach ($cities_in_database as $city) {
$cities[$city->getName()] = $city;
}
$form->add('city', ChoiceType::class, [
'choices' => $cities,
'mapped' => false,
]);
}
}
else if (get_class($entity_parent) === 'App\Entity\City') {
if (!$entity_parent->getUniversities()->count()) {
$form->add('university', ChoiceType::class, [
'choices' => null,
]);
}
else {
$university_in_database = $entity_parent->getUniversities();
foreach ($university_in_database as $university) {
$universities[$university->getName()] = $university;
}
$form->add('university', ChoiceType::class, [
'choices' => $universities,
]);
}
}
};
$builder->addEventListener(
FormEvents::PRE_SET_DATA,
function (FormEvent $event) use ($options, $formModifier, $builder) {
$region = $options['regions_array'][array_key_first($options['regions_array'])];
$city = $region->getCities()[0];
$formModifier($event->getForm(), $region);
$formModifier($event->getForm(), $city);
}
);
$builder->get('region')->addEventListener(
FormEvents::POST_SUBMIT,
function (FormEvent $event) use ($formModifier) {
$region = $event->getForm()->getData();
$city = $region->getCities()[0];
$formModifier($event->getForm()->getParent(), $region);
$formModifier($event->getForm()->getParent(), $city);
}
);
$builder->get('city')->addEventListener(
FormEvents::POST_SUBMIT,
function (FormEvent $event) use ($formModifier) {
$city = $event->getForm()->getData();
$formModifier($event->getForm()->getParent(), $city);
}
);
}
public function configureOptions(OptionsResolver $resolver)
{
$resolver->setDefaults([
'data_class' => Faculty::class,
'regions_array' => null,
]);
$resolver->setAllowedTypes('regions_array', 'array');
}
}
Controller:
/**
* #Route("/admin/insert/faculty", name="faculty")
*/
public function faculty(Request $request)
{
$regions_in_database = $this->getDoctrine()->getRepository(Region::class)->findAll();
$regions = [];
foreach ($regions_in_database as $region) {
$regions[(string)$region->getName()] = $region;
}
$faculty = new Faculty();
$insert_faculty = $this->createForm(InsertFacultyType::class, $faculty, [
'regions_array' => $regions,
]);
if (!$regions_in_database) {
$insert_faculty->addError(new FormError("There are no regions!"));
}
$insert_faculty->handleRequest($request);
if ($insert_faculty->isSubmitted() && $insert_faculty->isValid()) {
$repository = $this->getDoctrine()->getRepository(University::class);
$faculty_in_database = $repository->findOneBy(
[
'name' => $faculty->getName(),
'university' => $faculty->getUniversity(),
]
);
if ($faculty_in_database) {
$insert_faculty->addError(new FormError('Such a faculty is already in the database!'));
}
else {
$faculty->setRating(0);
if(!$faculty->getUniversity()) {
$insert_faculty->addError(new FormError("Select the university!"));
}
else {
$entity_manager = $this->getDoctrine()->getManager();
$entity_manager->persist($faculty);
$entity_manager->flush();
$this->addFlash(
'success',
'Faculty "' . $faculty->getName() . '" successfully saved!'
);
}
}
}
return $this->render('admin/insert/faculty/faculty.html.twig', [
'insert_faculty' => $insert_faculty->createView(),
]);
}

Answer 1

I invite you to use the Symfony debug toolbar. It will allow you to see the different problems associated with your code and give much more information about the problems that appear.
Profiler Symfony
About your problem, I think it is necessary to debug at the level of what your form sends to your application. But if you want more help, you must provide the error message that come with your 500 error.