hydra-sql/vendor/symfony/form/DataTransformerInterface.php

93 lines
3.7 KiB
PHP

<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Form;
use Symfony\Component\Form\Exception\TransformationFailedException;
/**
* Transforms a value between different representations.
*
* @author Bernhard Schussek <bschussek@gmail.com>
*/
interface DataTransformerInterface
{
/**
* Transforms a value from the original representation to a transformed representation.
*
* This method is called when the form field is initialized with its default data, on
* two occasions for two types of transformers:
*
* 1. Model transformers which normalize the model data.
* This is mainly useful when the same form type (the same configuration)
* has to handle different kind of underlying data, e.g The DateType can
* deal with strings or \DateTime objects as input.
*
* 2. View transformers which adapt the normalized data to the view format.
* a/ When the form is simple, the value returned by convention is used
* directly in the view and thus can only be a string or an array. In
* this case the data class should be null.
*
* b/ When the form is compound the returned value should be an array or
* an object to be mapped to the children. Each property of the compound
* data will be used as model data by each child and will be transformed
* too. In this case data class should be the class of the object, or null
* when it is an array.
*
* All transformers are called in a configured order from model data to view value.
* At the end of this chain the view data will be validated against the data class
* setting.
*
* This method must be able to deal with empty values. Usually this will
* be NULL, but depending on your implementation other empty values are
* possible as well (such as empty strings). The reasoning behind this is
* that data transformers must be chainable. If the transform() method
* of the first data transformer outputs NULL, the second must be able to
* process that value.
*
* @param mixed $value The value in the original representation
*
* @return mixed
*
* @throws TransformationFailedException when the transformation fails
*/
public function transform($value);
/**
* Transforms a value from the transformed representation to its original
* representation.
*
* This method is called when {@link Form::submit()} is called to transform the requests tainted data
* into an acceptable format.
*
* The same transformers are called in the reverse order so the responsibility is to
* return one of the types that would be expected as input of transform().
*
* This method must be able to deal with empty values. Usually this will
* be an empty string, but depending on your implementation other empty
* values are possible as well (such as NULL). The reasoning behind
* this is that value transformers must be chainable. If the
* reverseTransform() method of the first value transformer outputs an
* empty string, the second value transformer must be able to process that
* value.
*
* By convention, reverseTransform() should return NULL if an empty string
* is passed.
*
* @param mixed $value The value in the transformed representation
*
* @return mixed
*
* @throws TransformationFailedException when the transformation fails
*/
public function reverseTransform($value);
}