Symfony Forms 101

Symfony forms are so hard! That's what I hear a lot, but it's not quite true. If you stick to a set of best practices, Forms work wonderfully well.

Join me for this session to see the tricks that you should have known when you did your last project.

1. Bernhard Schussek · webmozart.io 1/100 https://www.flickr.com/photos/pennuja/5364128968 (CC BY 2.0) Symfony Forms 101 Bernhard Schussek (@webmozart) – Symfony Catalunya 2016
2. Bernhard Schussek · webmozart.io 4/100 Bernhard Schussek Freelancer, Trainer and Coach Symfony Architecture Coding Practices webmozart.io
3. Bernhard Schussek · webmozart.io 5/100 @webmozart
4. Bernhard Schussek · webmozart.io 6/100 What's the hardest part of Symfony?
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9. Bernhard Schussek · webmozart.io 11/100 Make simple cases simple, make complex cases possible ✓
10. Bernhard Schussek · webmozart.io 12/100 Forms are not as hard as you think
11. Bernhard Schussek · webmozart.io 13/100 PlaceOrderType Controller FormFactory createForm() buildForm() FormBuilder Form
12. Bernhard Schussek · webmozart.io 14/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() FormBuilder Form Order FormView update validate()
13. Bernhard Schussek · webmozart.io 15/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
14. Bernhard Schussek · webmozart.io 16/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
15. Bernhard Schussek · webmozart.io 17/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
16. Bernhard Schussek · webmozart.io 18/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
17. Bernhard Schussek · webmozart.io 19/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
18. Bernhard Schussek · webmozart.io 20/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
19. Bernhard Schussek · webmozart.io 21/100 My Best Practices
20. Bernhard Schussek · webmozart.io 22/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
21. Bernhard Schussek · webmozart.io 23/100 ✓ Use PhpStorm
22. Bernhard Schussek · webmozart.io 24/100 $form = $this->createForm(PaymentType::class, $order, [ 'action' => $this->generateUrl('payment_gw'), ]); ✓ Use "action" option in the controller
23. Bernhard Schussek · webmozart.io 25/100 $form = $this->createForm(PaymentType::class, $order, [ 'method' => 'PUT', ]); ✓ Use "method" option in the controller
24. Bernhard Schussek · webmozart.io 26/100 $defaultShipping = $this->getDefaultShipping($customer); $form = $this->createForm( new PlaceOrderType($defaultShipping), ); ✗ Don't Pass Dynamic Data to Constructor
25. Bernhard Schussek · webmozart.io 27/100 $defaultShipping = $this->getDefaultShipping($customer); $form = $this->createForm(PlaceOrderType::class, .., [ 'default_shipping' => $defaultShipping, ]); ✓ Use Custom Options
26. Bernhard Schussek · webmozart.io 28/100 parameters: app.us_shipping.enabled: true services: app.form.shipping: class: AppBundle\Form\ShippingType arguments: - %app.us_shipping.enabled% tags: - { type: form.type } ✓ Pass Global Settings To Constructor
27. Bernhard Schussek · webmozart.io 29/100 class ShippingType extends AbstractType { private $usShipping; public function __construct($usShipping) { $this->usShipping = (bool) $usShipping; } // ... } ✓ Pass Global Settings To Constructor
28. Bernhard Schussek · webmozart.io 30/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
29. Bernhard Schussek · webmozart.io 31/100 {{ form(form) }} ✓ Use form(form) for Rapid Prototyping
30. Bernhard Schussek · webmozart.io 32/100 {{ form_row(form.firstName) }} {{ form_row(form.lastName) }} {{ form_row(form.address) }} {{ form_row(form.submit) }} ✓ Use form_row() to Control Field Order
31. Bernhard Schussek · webmozart.io 33/100 {{ form_row(form.address, { 'label': 'Your Address', 'attr': {'class': 'shippable-address'}, 'label_attr': {'data-id': 5} }) }} ✓ Set Labels/Attributes in the Template
32. Bernhard Schussek · webmozart.io 34/100 ✓ Use the Form Debugger
33. Bernhard Schussek · webmozart.io 35/100 <div class="form-group"> {{ form_errors(form.paymentMethod) }} <label for="{{ form.paymentMethod.vars.id }}"> Payment Method {{ form_widget(form.paymentMethod) }} </label> </div> ✓ Write Custom HTML By Hand
34. Bernhard Schussek · webmozart.io 36/100 {% form_theme form 'my-theme.html.twig' %} {{ form(form) }} ✗ (Mostly) Don't Use Themes
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36. Bernhard Schussek · webmozart.io 38/100 public function buildForm($builder, array $options) { $fields = $this->fieldRepository->findAll(); $fieldsForm = $builder->create('fields', FormType::c foreach ($fields as $field) { $fieldsForm->add($field->getName(), $field->getT } $builder->add($fieldsForm); }
37. Bernhard Schussek · webmozart.io 39/100 public function finishView($view, $form) { $fieldViews = $view->children['fields']; $tabs = $this->tabRespository->findAll(); foreach ($tabs as $tab) { $tabView = new FormView(); $tabView->vars['label'] = $tab->getName() // reorganize field views... $view->children['tabs'][] = $tabView; } } ✓ Move Complex Logic to build/finishView()
38. Bernhard Schussek · webmozart.io 40/100 {% for tab in form.tabs %} {{ tab.vars.label }} {% for field in tab %} {{ form_row(field) }} {% endfor %} {% endfor %}
39. Bernhard Schussek · webmozart.io 41/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
40. Bernhard Schussek · webmozart.io 42/100 /** * @Assert\NotNull * @Assert\GreaterThan(0) */ private $cost; ✗ Don't Add "Assert" Alias
41. Bernhard Schussek · webmozart.io 43/100 ✓ Use PhpStorm with the Annotation Plugin
42. Bernhard Schussek · webmozart.io 44/100 /** * @NotNull * @GreaterThan(0) */ private $cost; ✓ Auto-Import Annotations
43. Bernhard Schussek · webmozart.io 46/100 /** * @Callback */ public function validateTotal( ExecutionContextInterface $context) { if ($this->total !== $this->getProductsTotal()) { $this->context->addViolation('Invalid.'); } } ✓ Use the @Callback Constraint
44. Bernhard Schussek · webmozart.io 47/100 $context->addViolation('product.total.invalid'); ✓ Use Message Keys
45. Bernhard Schussek · webmozart.io 48/100 $context->buildViolation('product.total.invalid') ->setParameter('{{ expected }}', $expected) ->addViolation(); ✓ Use Message Parameters
46. Bernhard Schussek · webmozart.io 49/100 /** * @NotNull * @GreaterThan(0, groups="Checkout") */ private $total; ✓ Use Validation Groups for Partial Validation
47. Bernhard Schussek · webmozart.io 50/100 public function configureOptions(OptionsResolver $resolv { $resolver->setDefaults([ 'validation_groups' => new GroupSequence([ 'Default', 'VatCheck' ]), ]); } ✓ Use Group Sequences for Sequential Validation
48. Bernhard Schussek · webmozart.io 51/100 class ProductName extends Regex { public function __construct($options = []) { parent::__construct(array_replace([ 'pattern' => '/^\w.*$/' ], $options); } public function validatedBy() { return RegexValidator::class; } } ✓ Create Domain-Specific Constraints
49. Bernhard Schussek · webmozart.io 52/100 class ProductNameValidator extends ConstraintValidator { public function validated($value, Constraint $constr { $this->context->getValidator() ->inContext($this->context) ->validate($value, new Regex(self::PATTERN)) ->validate($value, new NotEqualTo('keyword') ; } } ✓ Create Composite Constraints
50. Bernhard Schussek · webmozart.io 53/100 class ProductNameValidator extends ConstraintValidator { public function validated($value, Constraint $constr { if (null === $value) { return; } // ... } } ✓ Ignore Null Values
51. Bernhard Schussek · webmozart.io 54/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
52. Bernhard Schussek · webmozart.io 55/100 Clark Kent ... Submit Name VAT $order->getCustomerName() $order->setCustomerName() Order +orderNumber +customerName +vat 1 2 3
53. Bernhard Schussek · webmozart.io 56/100 $builder->add('vat', TextType::class, [ 'property_path' => 'customer.vatId' ]); ✓ Decouple Forms from the Model Structure
54. Bernhard Schussek · webmozart.io 57/100 'customer.name' == $data->getCustomer()->setName() 'items[0].amount' == $data->getItems()[0]->setAmount() ✓ Learn Property Paths
55. Bernhard Schussek · webmozart.io 58/100 class Customer { public function __construct($name, Address $address) { // ... } } What About Non-Empty Constructors?
56. Bernhard Schussek · webmozart.io 59/100 public function configureOptions(OptionsResolver $resolv { $resolver->setDefaults([ 'empty_data' => function (FormInterface $form) { return new Customer( $form->get('name')->getData(), $form->get('address')->getData() ); }, ]); } ✓ Use "empty_data" for Non-Empty Constructors
57. Bernhard Schussek · webmozart.io 60/100 class Money { public function __construct($amount) { $this->amount = $amount; } public function getAmount() { return $this->amount; } } What About Value Objects?
58. Bernhard Schussek · webmozart.io 61/100 Model Format View Format ProductRef string ProductRefType
59. Bernhard Schussek · webmozart.io 62/100 Model Format View Format Money string MyMoneyType
60. Bernhard Schussek · webmozart.io 63/100 class MyMoneyType extends AbstractType implements DataTransformerInterface { public function buildForm( FormBuilderInterface $builder, array $options) { $builder->addModelTransformer($this); } public function getParent() { return MoneyType::class; } // ... } ✓ Use Data Transformers (1/3)
61. Bernhard Schussek · webmozart.io 64/100 class MyMoneyType extends AbstractType implements DataTransformerInterface { // ... public function transform($money) { if (null === $money) { return null; } return $money->getAmount(); } // ... } ✓ Use Data Transformers (2/3)
62. Bernhard Schussek · webmozart.io 65/100 class MyMoneyType extends AbstractType implements DataTransformerInterface { // ... public function reverseTransform($amount) { if (null === $amount) { return null; } return new Money($amount); } } ✓ Use Data Transformers (3/3)
63. Bernhard Schussek · webmozart.io 66/100 class Customer { public function relocate(Address $address) { // ... } } What About Non-Standard Methods?
64. Bernhard Schussek · webmozart.io 67/100 Clark Kent ... Submit Name VAT $order->getCustomerName() $order->setCustomerName() Order +orderNumber +customerName +vat 1 2 3
65. Bernhard Schussek · webmozart.io 68/100 class CustomerType extends AbstractType implements DataMapperInterface { public function buildForm( FormBuilderInterface $builder, array $options) { $builder->setDataMapper($this); } // ... } ✓ Use Data Mappers (1/3)
66. Bernhard Schussek · webmozart.io 69/100 class CustomerType extends AbstractType implements DataMapperInterface { // ... public function mapDataToForms($customer, $forms) { $forms = iterator_to_array($forms); $forms['address']->setData($customer->getAddress // ... } // ... } ✓ Use Data Mappers (2/3)
67. Bernhard Schussek · webmozart.io 70/100 class CustomerType extends AbstractType implements DataMapperInterface { // ... public function mapFormsToData($forms, &$customer) { $forms = iterator_to_array($forms); $customer->relocate($forms['address']->getData() // ... } // ... } ✓ Use Data Mappers (3/3)
68. Bernhard Schussek · webmozart.io 75/100 PlaceOrderType FormFactory Controller createForm() buildForm() Form handleRequest() Order Validator createView() Twig FormBuilder Form Order FormView FormView update validate() render()
69. Bernhard Schussek · webmozart.io 76/100 $builder->add('expressShipping', ChoiceType::class, [ 'choices' => [ 'Decide later' => Selection::get(LATER), 'No' => Selection::get(NO), 'Yes' => Selection::get(YES), ], 'choices_as_values' => true, ]); ✓ Learn the Options of ChoiceType
70. Bernhard Schussek · webmozart.io 77/100 $builder->add('expressShipping', ChoiceType::class, [ // ... // $shipping->getTitle() 'choice_label' => 'title', ]); <select> <option value="0">Decide later</option> <option value="1">No</option> <option value="2">Yes</option> </select>
71. Bernhard Schussek · webmozart.io 78/100 $builder->add('expressShipping', ChoiceType::class, [ // ... 'choice_label' => function (Selection $selection) { return humanize($selection->getType()); }, ]); <select> <option value="0">Decide later</option> <option value="1">No</option> <option value="2">Yes</option> </select>
72. Bernhard Schussek · webmozart.io 79/100 $builder->add('expressShipping', ChoiceType::class, [ // ... // $selection->getType() 'choice_value' => 'type' ]); <select> <option value="later">Decide later</option> <option value="no">No</option> <option value="yes">Yes</option> </select>
73. Bernhard Schussek · webmozart.io 80/100 $builder->add('paymentMethod', ChoiceType::class, [ // ... // $paymentMethod->getCategory()->getName() 'group_by' => 'category.name', ]); <select> <optgroup label="Credit Card"> ... </optgroup> ... </select>
74. Bernhard Schussek · webmozart.io 81/100 $builder ->add('country', 'entity', [ ... ]) ->add('province', 'entity', [ ... ]) ; What About Field Dependencies?
75. Bernhard Schussek · webmozart.io 82/100 $builder->get('country')->addEventListener( FormEvents::POST_SET_DATA, $addProvinceField ); $builder->get('country')->addEventListener( FormEvents::POST_SUBMIT, $addProvinceField ); ✓ Use POST_* Hooks On Fields (1/2)
76. Bernhard Schussek · webmozart.io 83/100 $addProvinceField = function (FormEvent $event) { $form = $event->getForm()->getParent(); $country = $event->getData(); $form->add('province', EntityType::class, [ 'class' => Province::class, 'query_builder' => function ($repo) use ($countr // query provinces by $country }, ]); }; ✓ Use POST_* Hooks On Fields (2/2)
77. Bernhard Schussek · webmozart.io 84/100 Forms and CRUD
78. Bernhard Schussek · webmozart.io 85/100 class Contact { private $firstName; private $lastName; private $email; private $phoneNumber; private $address; // accessor methods... } Example: Contact Details
79. Bernhard Schussek · webmozart.io 86/100 $contact = $this->contactRepository->get($contactId); $form = $this->createForm(ContactType::class, $contact); $form->handleRequest($request); if ($form->isSubmitted() && $form->isValid()) { $this->contactRepository->flush($contact); } ✓ Easy to Fetch/Update
80. Bernhard Schussek · webmozart.io 87/100 class Contact { // ... public function setAddress(Address $address) { $this->address = $address; } } ✓ Write Strict Method Signatures
81. Bernhard Schussek · webmozart.io 88/100 class ContactType extends AbstractType { public function buildForm($builder, array $options) { // ... $builder->add('address', AddressType::class, [ 'constraints' => new NotNull(), ]); } } ✓ Place Validation Constraints in the Form
82. Bernhard Schussek · webmozart.io 89/100 class ContactType extends AbstractType implements DataMapperInterface { public function buildForm($builder, array $options) { $builder->setDataMapper($this); } // ... } ✓ Write Your Own Data Mapper
83. Bernhard Schussek · webmozart.io 90/100 class ContactType implements DataMapperInterface { // ... public function mapDataToForms($data, $forms) { $forms = iterator_to_array($forms); if (!$data instanceof Contact) { return null; } $forms['firstName']->setData($data->getFirstName $forms['lastName']->setData($data->getLastName() $forms['email']->setData($data->getEmail()); $forms['phoneNumber']->setData($data->getPhoneNu $forms['address']->setData($data->getAddress()); } // ... }
84. Bernhard Schussek · webmozart.io 91/100 class ContactType implements DataMapperInterface { // ... public function mapFormsToData($forms, &$data) { $forms = iterator_to_array($forms); if (!$data instanceof Contact) { $data = new Contact(); } $data->setFirstName($forms['firstName']->getData $data->setLastName($forms['lastName']->getData() $data->setEmail($forms['email']->getData()); $data->setPhoneNumber($forms['phoneNumber']->get if (null !== $forms['address']->getData()) { $data->setAddress($forms['address']->getData } } }
85. Bernhard Schussek · webmozart.io 92/100 KISS
86. Bernhard Schussek · webmozart.io 93/100 No Home for Business Logic
87. Bernhard Schussek · webmozart.io 94/100 Forms and DDD/CQRS
88. Bernhard Schussek · webmozart.io 95/100 class Contact { ... } Aggregate Root class ContactCommandHandler { ... } Command Handler class ModifyContact { ... } Command
89. Bernhard Schussek · webmozart.io 96/100 $commandBus->dispatch( new ModifyContact($fieldValues) ); ✓ Dispatch Commands in the Controller
90. Bernhard Schussek · webmozart.io 97/100 public function handleModifyContact(ModifyContact $comma $contact = $this->repo->get($command->getContactId() $fields = $this->fieldRepo->getMany( array_keys($command->getFieldValues()) ); $contact->modify($fields, $command->getFieldValues() $this->repo->flush(); } ✓ Handle in the Command Handler
91. Bernhard Schussek · webmozart.io 98/100 class Contact { public function modify(array $fields, array $values) { foreach ($values as $fieldName => $value) { if (!$fields[$fieldName]->accepts($value)) { throw new Exception(); } } // ... } } ✓ Aggregate Roots Control Business Rules
92. Bernhard Schussek · webmozart.io 99/100 What about Forms?
93. Bernhard Schussek · webmozart.io 100/100 public function mapDataToForms($data, $forms) { $forms = iterator_to_array($forms); if (!$data instanceof Contact) { return; } $forms['fieldValues']->setData($data->getFieldValues } ✓ Map Aggregates (CQRS: View Models) to Forms
94. Bernhard Schussek · webmozart.io 101/100 public function mapFormsToData($forms, &$data) { $forms = iterator_to_array($forms); $data = new ModifyContact( $forms['fieldValues']->getData() ); } ✓ Map Aggregates to Forms
95. Bernhard Schussek · webmozart.io 102/100 Lots of Boilerplate
96. Bernhard Schussek · webmozart.io 103/100 Well-Structured Business Logic
97. Bernhard Schussek · webmozart.io 104/100 CRUD or DDD or CQRS?
98. Bernhard Schussek · webmozart.io 105/100 Forms can be simple if done right!
99. Bernhard Schussek · webmozart.io 106/100 Complex things remain complex...
100. Bernhard Schussek · webmozart.io 107/100 Questions? Questions? Bernhard Schussek Bernhard Schussek @webmozart @webmozart webmozart.io