Validation with Symfony2 from a Drupal Perspective: DrupalCon Austin Session Notes

• Symfony is a set of reusable components. Drupal 8 uses 12 of these components.
• Install with composer: "symfony/validator"

Validator Object

• $validator = Validation::createValidator();
  $validator->validateValue('[email protected]', new Email()); // Email is a constraint class

• Combine constraints: $validator->value('wayne', array(new Length('min' => 5, 'max' => 15)), new Regex(array('pattern' => '/XXXX/'))

• Can also validate whole objects.
• validateValue(), validateProperty($user, 'email'), validationPropertyValue($user, 'email', '[email protected]'), validate($user)
• ConstraintViolationList is a collection of validation failures

Constraint and ConstraintValidator

• public properties = options for a Constraint subclass
• class Regex, class RegexValidator. The Validator does the logic of validating in the validate() function
• BasicConstraints: NotBlank(), Blank(), NotNull(), Null(), True(), False(), Url(), Ip(), Length(), Email()
• Comparison Constraints
• Date and Time constraints
• Number and Financial Constraints: Currency(), CardScheme(), Iban(), Isbn()
• Image Constraints: mimetypes, size, width, height
• Collection Constraints: check all the values in an array

Object Validation Mapping

• Can be definied in PHP, YML, XML, or Annotations
• For each property of the object, you define the validation constratints in a validation builder
• Annotations allow you to keep the validation rules right with the properties in the file.
• Can have the validator validate sub-objects automatically.
• Can apply constraints on methods as well as properties
• You can apply Callback constraints to use methods to validate a property

Validation Groups

• Allows for validation rules to change based on context
• For example, user registration versus user edit profile
• Group Sequence allows you to break validation into steps

Slides, for Example Code