Validation with Symfony2

When was the last time you wrote a web application without having to validate some data or user input? Probably long ago. In fact, validation is so important that most developers take a profound validation system for granted. Maybe that also explains why few people even realize that Drupal 8 uses a completely new validation engine underneath: The tried and tested Symfony2 Validator component.

In my talk, I will show you how to use the Validator component both in regular PHP applications and in Drupal 8. You will learn how the component works internally and how a few simple mechanisms will help you to fulfill most of your validation needs - from small websites to big enterprise applications.

1. Validation with Symfony2 from a Drupal perspective Tuesday, June 3rd 2014 – Austin, TX – United States
2. Validation with Symfony2 from a Drupal perspective Tuesday, June 3rd 2014 – Austin, TX – United States
3. Hugo HAMON Head of training at SensioLabs Book author Speaker at Conferences Symfony contributor @hhamon
6. Introduction
7. Don’t trust ANY user inputs! https://www.flickr.com/photos/ferran-jorda
8. Check data consistency Check data format Filter data Check data integrity
9. https://www.flickr.com/photos/87913776@N00/5129625865/sizes/l/in/photostream/
10. What is Symfony2?
11. Framework Philosophy Community
12. Symfony2 is a set of reusable, standalone, decoupled, and cohesive PHP components that solve common web development problems.
13. Symfony is also a full stack web framework made of bundles and third party libraries.
14. Dependency Injection BrowserKit ClassLoader Config Console CssSelector Debug DomCrawler EventDispatcher ExpressionLanguage Filesystem Finder Form HttpFoundation HttpKernel Locale Intl Icu OptionsResolver Process PropertyAccess Routing Security Serializer Stopwatch Templating Translation Validator Yaml
15. Dependency Injection BrowserKit ClassLoader Config Console CssSelector Debug DomCrawler EventDispatcher ExpressionLanguage Filesystem Finder Form HttpFoundation HttpKernel Locale Intl Icu OptionsResolver Process PropertyAccess Routing Security Serializer Stopwatch Templating Translation Validator Yaml
16. Getting Started
17. Installation # composer.json { "require": { "symfony/validator": "~2.4" } }
18. Getting a validator use Symfony\Component\Validator\Validation; $validator = Validation::createValidator();
19. Validating a single value use Symfony\Component\Validator\Constraints\Email; use Symfony\Component\Validator\Validation; $validator = Validation::createValidator(); $errors = $validator->validateValue('foo@bar.tld', new Email()); echo count($errors) ? 'Invalid' : 'Valid';
20. Combining constraints use Symfony\Component\Validator\Constraints\Email; use Symfony\Component\Validator\Constraints\Regex; $errors = $validator->validateValue('hhamon', array( new Length(array('min' => 5, 'max' => 15)), new Regex(array('pattern' => '/^[a-z]+/i')), ));
21. The API
22. Validator The validator validates a value, an object property or a whole object against a set of constraints.
23. Validator $user = new User('foo@bar.tld'); $validator->validateValue($user->email, new Email()); $validator->validateProperty($user, 'email'); $validator->validatePropertyValue($user, 'email', 'foo@bar.tld'); $validator->validate($user);
24. ConstraintViolationList The constraint violation list is a collection of validation failures generated by the validator object.
25. ConstraintViolationList $errors = $validator->validate($user); foreach ($errors as $error) { echo $error; echo "\n"; }
26. Constraint A constraint is an object that describes an assertive statement to trigger on the value to validate.
27. Constraint class Regex extends Constraint { public $message = 'This value is not valid.'; public $pattern; public $htmlPattern = null; public $match = true; } Options
28. ConstraintValidator A constraint validator is the object that triggers the validation logic on the value against its corresponding validation constraints.
29. class RegexValidator extends ConstraintValidator { public function validate($value, Constraint $constraint) { if (null === $value || '' === $value) { return; } if ($constraint->match xor preg_match($constraint->pattern, $value)) { $this->context->addViolation( $constraint->message, array('{{ value }}' => $value) ); } } }
30. Basic Constraints $constraint = new NotBlank(); $constraint = new Blank(); $constraint = new NotNull(); $constraint = new Null(); $constraint = new True(); $constraint = new False(); $constraint = new Type(array('type' => 'int'));
31. String Constraints $constraint = new Url(); $constraint = new Ip(); $constraint = new Regex([ 'pattern' => '#\d+#' ]); $constraint = new Email([ 'checkMX' => true ]); $constraint = new Length([ 'min' => 1, 'max' => 6, ]);
32. Comparison Constraints $constraint = new EqualTo([ 'value' => 6 ]); $constraint = new NotEqualTo([ 'value' => 6 ]); $constraint = new IdenticalTo([ 'value' => 6 ]); $constraint = new NotIdenticalTo([ 'value' => 6 ]); $constraint = new LessThan([ 'value' => 6 ]); $constraint = new LessThanOrEqual([ 'value' => 6 ]); $constraint = new GreaterThan([ 'value' => 6 ]); $constraint = new GreaterThanOrEqual([ 'value' => 6 ]);
33. Date & Time Constraints $constraint = new Date(); $constraint = new DateTime(); $constraint = new Time();
34. Number & Financial Constraints $constraint = new Currency(); $constraint = new Luhn(); $constraint = new Iban(); $constraint = new Range([ 'min' => 1, 'max' => 6 ]); $constraint = new Issn([ 'caseSensitive' => true ]); $constraint = new Isbn([ 'isbn10' => true, 'isbn13' => true, ]); $constraint = new CardScheme([ 'schemes' => [ 'AMEX', 'VISA' ], ]);
35. File Constraints $constraint = new File([ 'mimeTypes' => [ 'application/pdf', 'text/plain' ], 'maxSize' => '8M', ]); $constraint = new Image([ 'mimeTypes' => [ 'image/jpg', 'image/png' ], 'maxSize' => '8M', 'minWidth' => 120, 'maxWidth' => 1024, 'maxHeight' => 120, 'minHeight' => 768, ]);
36. Collection Constraints $constraint = new Language(); $constraint = new Locale(); $constraint = new Country(); $constraint = new Count(['min' => 2, 'max' => 5 ]); $constraint = new Choice([ 'choices' => range(10, 99), 'multiple' => true, 'min' => 2, 'max' => 5, ]);
37. Collection Constraints $collection = new Collection([ 'allowExtraFields' => true, 'fields' => [ 'fullName' => [ new NotBlank(), new Length([ 'min' => 2, 'max' => 30 ]), ], 'emailAddress' => [ new NotBlank(), new Email(), ], ], ]);
38. Other Constraints $constraint = new Valid(); $constraint = new UserPassword(); $constraint = new Callback([ 'callback' => 'checkPassword' ]); $constraint = new Expression([ 'expression' => "this.isTierStatus() in ['gold', 'platinum']", 'message' => 'Customer is not premium member', ]); $constraint = new All(['constraints' => [ new NotBlank(), new Email(), ]]);
39. Object Validation Mapping
40. The validator component supports four validation mapping drivers: PHP, YAML, XML & Annotations.
41. ValidatorBuilder The validator builder builds and configures the validator object.
42. $loader = require_once __DIR__.'/vendor/autoload.php'; use Doctrine\Common\Annotations\AnnotationRegistry; use Symfony\Component\Validator\Validation; // Required to load annotations AnnotationRegistry::registerLoader([ $loader, 'loadClass' ]); $validator = Validation::createValidatorBuilder() ->addMethodMapping('loadValidatorMetadata') ->addYamlMapping(__DIR__.'/validation.yml') ->addXmlMapping(__DIR__.'/validation.xml') ->enableAnnotationMapping() ->getValidator() ;
43. PHP Validation Metadata Mapping
44. namespace Shop; use Symfony\Component\Validator\Constraints\Email; use Symfony\Component\Validator\Constraints\Length; use Symfony\Component\Validator\Constraints\NotBlank; use Symfony\Component\Validator\Constraints\Regex; use Symfony\Component\Validator\Mapping\ClassMetadata; class Order { private $reference; private $customer; // ... public static function loadValidatorMetadata(ClassMetadata $md) { $md->addPropertyConstraint('reference', new NotBlank()); $md->addPropertyConstraint('reference', new Length(['min' => 10, 'max' => 10])); $md->addPropertyConstraint('reference', new Regex(['pattern' => '/[A-Z0-9]+/' ])); $md->addPropertyConstraint('customer', new NotBlank()); $md->addPropertyConstraint('customer', new Email()); } }
45. YAML Validation Metadata Mapping
46. Shop\Order: properties: reference: - NotBlank: ~ - Length: { min: 10, max: 10 } - Regex: "/[A-Z0-9]+/" customer: - NotBlank: ~ - Email: ~ YAML validation mapping
47. XML Validation Metadata Mapping
48. <?xml version="1.0" encoding="UTF-8"?> <constraint-mapping> <class name="Shop\Order"> <property name="reference"> <constraint name="NotBlank"/> <constraint name="Length"> <option name="min"> <value>8</value> </option> <option name="max"> <value>32</value> </option> </constraint> <constraint name="Regex"> <option name="pattern"> <value>/[A-Z0-9]+/</value> </option> </constraint> </property> <property name="customer"> <constraint name="NotBlank"/> <constraint name="Email"/> </property> </class> </constraint-mapping> Constraint + options
49. Annotations Validation Metadata Mapping
50. Installation { "require": { "doctrine/cache": "~1.3", "doctrine/annotations": "~1.1", "symfony/validator": "~2.4" } }
51. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; class Order { /** * @Assert\NotBlank * @Assert\Length(min = 10, max = 10) * @Assert\Regex("/[A-Z0-9]+/") */ private $reference; /** * @Assert\NotBlank * @Assert\Email */ private $customer; }
52. Let’s take a real world example!
54. namespace Shop; class Order { private $reference; private $customer; private $lines = array(); // ... }
55. Validating the reference & customer email address
56. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; class Order { /** * @Assert\NotBlank * @Assert\Length(min = 10, max = 10) * @Assert\Regex(pattern = "/[A-Z0-9]+/") */ private $reference; /** * @Assert\NotBlank * @Assert\Email */ private $customer; }
57. $order = new Order( 'ççç', 'foo@bar' );
58. $errors = $validator ->validate($order) ;
59. Shop\Order.reference: This value should have exactly 10 characters. Shop\Order.reference: This value is not valid. Shop\Order.customer: This value is not a valid email address.
60. Validating the number of ordered items
61. The order must be valid if it contains at least one lines and less than ten.
62. $order = new \Shop\Order('XXX0123YYY', 'hugo@example.com'); $order->addLine([ 'quantity' => 2, 'price' => 650, 'reference' => 'SF2C1', 'designation' => 'Getting Started with Symfony', ]); $order->addLine([ 'quantity' => 1, 'price' => 990, 'reference' => 'SF2C2', 'designation' => 'Mastering Symfony', ]);
63. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; class Order { /** * @Assert\Count( * min = 1, * max = 10, * minMessage = "You must have at least one item.", * maxMessage = "You can't order more than 10 items." * ) */ private $lines = array(); }
64. Validating the collection of ordered items
65. Each item set into the order is an associative array. We want to validate the data in each array.
66. $order->addLine([ 'quantity' => 2, 'price' => 650, 'reference' => 'SF2C1', 'designation' => 'Getting ... ', ]);
67. class Order { /** * @Assert\Count(...) * @Assert\All( * @Assert\Collection( * fields = { * "reference" = @Assert\Required(@Assert\NotBlank), * "quantity" = @Assert\Required({ * @Assert\NotBlank, * @Assert\Type("int"), * @Assert\Range(min = 1) * }), * "price" = @Assert\Required({ * @Assert\Type("double"), * @Assert\Range(min = 0) * }), * "designation" = @Assert\Optional * } * ) * )) */ private $lines = array(); }
68. o_O
69. Of course, there is a better path to achieve this with objects validation.
70. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; class OrderLine { /** @Assert\NotBlank */ private $reference; /** * @Assert\NotBlank * @Assert\Type("int") * @Assert\Range(min = 1) */ private $quantity; /** * @Assert\NotNull * @Assert\Type("double") * @Assert\Range(min = 0) */ private $price; private $designation; }
71. $item1 = new OrderLine('SF2C1', 650, 2, 'Get...'); $item2 = new OrderLine('SF2C2', 990, 1); $order = new Order('XXX0123YYY', 'hugo@foo.com'); $order->addLine($item1); $order->addLine($item2); Using OrderLine objects
72. class Order { /** * @Assert\Count( * min = 1, * max = 10, * minMessage = "You must ... one item.", * maxMessage = "You can't ... 10 items." * ) * @Assert\Valid */ private $lines = array(); }
73. Validating a coupon code
74. The coupon must equal a specific code to be valid.
75. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; class Order { /** * @Assert\EqualTo( * value = "DRUPALCON2014" * message = "Coupon code is not valid." * ) */ private $coupon; // ... }
76. The coupon is also valid with at least 3 ordered items and a minimum purchase of $850 USD.
77. class Order { /** * @Assert\EqualTo( * value = "DRUPALCON2014" * message = "Coupon code is not valid." * ) * * @Assert\Expression( * expression = "this.getNbItems() > 2 and this.getSubtotal() > 850", * message = "Coupon is valid with 3+ items and at $850+ purchase." * ) */ private $coupon; // ... } Symfony > 2.4
78. Validating the customer’s billing and delivery address
79. In an address, if the country is United States or Canada, the state (or province) must be set as well.
80. class Order { /** * @Assert\NotBlank * @Assert\Valid */ private $billingAddress; /** * @Assert\NotBlank * @Assert\Valid */ private $deliveryAddress; }
81. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; class Address { /** @Assert\NotBlank */ private $street; /** @Assert\NotBlank */ private $zipCode; /** @Assert\NotBlank */ private $city; /** @Assert\Country */ private $country; private $state; public function __construct($street, $zipCode, $city, $country, $state = null) { // ... } }
82. class Address { /** * @Assert\False( * message = "State/province is required for USA/Canada." * ) */ public function isStateRequiredAndFilled() { if (!in_array($this->country, [ 'CA', 'US' ])) { return false; } return empty($this->state); } }
83. Shop\Order.lines[0].price: This value should be of type double. Shop\Order.lines[1].price: This value should be of type double. Shop\Order.coupon: Coupon is valid with 3 or more items and at least $850 purchase. Shop\Order.billingAddress.stateRequiredAndFilled: State/province is required for USA/Canada. Method Getter Constraint
84. Dealing with the validation ExecutionContext
85. The getter method constraint doesn’t allow to attach the violation to a particular property (ie: state).
86. This can be done with the Class Callback validation constraint and the ExecutionContext object.
87. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; use Symfony\Component\Validator\ExecutionContext; /** @Assert\Callback("enforceStateInNorthAmerica") */ class Address { function enforceStateInNorthAmerica(ExecutionContext $context) { if (!in_array($this->country, [ 'CA', 'US'])) { return; } if (empty($this->state)) { $context->addViolationAt('state', 'State is mandatory.'); } } }
88. Shop\Order.lines[0].price: This value should be of type double. Shop\Order.lines[1].price: This value should be of type double. Shop\Order.coupon: Coupon is valid with 3 or more items and at least $850 purchase. Shop\Order.billingAddress.state: State is mandatory. Method Getter Constraint
89. Creating a custom validator constraint
90. What about validating the state/province code is a valid North America state/province code?
91. namespace Shop\Validator\Constraints; use Symfony\Component\Validator\Constraint; /** * @Annotation * @Target({"CLASS", "ANNOTATION"}) */ class NorthAmericaState extends Constraint { public $message = 'State code is not valid.'; public function getTargets() { return self::CLASS_CONSTRAINT; } }
92. namespace Shop\Constraints; use Shop\Address; use Symfony\Component\Validator\Constraint; use Symfony\Component\Validator\ConstraintValidator; use Symfony\Component\Validator\Exception\UnexpectedTypeException; class NorthAmericaStateValidator extends ConstraintValidator { private static $regions = [ 'US' => [ 'NV', 'CA', 'DC', 'FL', 'VG', 'NY', 'OR', … ], 'CA' => [ 'QC', 'AB', … ], ]; public function validate($value, Constraint $constraint) { // ... } }
93. class NorthAmericaStateValidator extends ConstraintValidator { // ... public function validate($value, Constraint $constraint) { if (!$value instanceof Address) { throw new UnexpectedTypeException($value, 'Shop\Address'); } $country = $value->getCountry(); if (!isset(self::$regions[$country])) { return; } $regions = self::$regions[$country]; if (!in_array($value->getState(), $regions)) { $this->context->addViolationAt('state', $constraint->message); } } }
94. namespace Shop; // ... use Shop\Validator\Constraints as ShopAssert; /** * @ShopAssert\NorthAmericaState */ class Address { // ... }
95. Advanced Mapping
96. Validation Groups
97. Validation groups Validation groups provide a simple way to contextualize the validation of an object.
98. class Order { /** * @Assert\NotBlank(groups = "Create") * @Assert\Length(min = 10, max = 10, groups = "Create") * @Assert\Regex(pattern = "/[A-Z0-9]+/", groups = "Create") */ private $reference; // ... } Attach validation groups
99. $errors = $validator->validate( $order, [ 'Default', 'Create' ] ); Validating against groups
100. Group Sequences
101. Group Sequences Group Sequences allow to validate an object in multiple steps.
102. /** * @Assert\GroupSequence(groups = { * "Order", "Shipping", "Payment" * }) */ class Order { /** @Assert\NotBlank */ private $reference; /** @Assert\NotBlank(groups = "Shipping") */ private $billingAddress; /** @Assert\NotBlank(groups = "Shipping") */ private $deliveryAddress; /** @Assert\NotBlank(groups = "Payment") */ private $payment; // ... }
103. $errors = $validator->validate($order, [ 'Default', 'Shipping', 'Payment', ]); Validating against sequences
104. Class Inheritance
105. Class inheritance The validator is able to execute validation rules located in both a child class and its parent.
106. namespace Shop; use Symfony\Component\Validator\Constraints as Assert; class ComplimentaryOrder extends Order { /** @Assert\EqualTo(0) */ protected $total; /** @Assert\EqualTo(0) */ protected $vat; // ... }
107. Translations
108. <?xml version="1.0"?> <xliff version="1.2"> <file source-language="en" datatype="plaintext"> <body> <trans-unit id="1"> <source>State code is not valid.</source> <target>L'Etat est invalide.</target> </trans-unit> </body> </file> </xliff>
109. use Symfony\Component\Validator\Validation; use Symfony\Component\Translation\Loader\XliffFileLoader; use Symfony\Component\Translation\Translator; $file = __DIR__.'/config/validators.fr.xlf'; $translator = new Translator('fr'); $translator->addLoader('xlf', new XliffFileLoader()); $translator->addResource('xlf', $file, 'fr'); $validator = Validation::createValidatorBuilder() ->enableAnnotationMapping() ->setTranslator($translator) ->getValidator() ;
110. Shop\ComplimentaryOrder.lines[0].price: This value should be of type double. Shop\ComplimentaryOrder.lines[1].price: This value should be of type double. Shop\ComplimentaryOrder.billingAddress.state: L'Etat ou la province est invalide.
112. Questions? h"p://www.flickr.com/photos/mkrigsman/