如何在 symfony2 中验证实体集合中的唯一实体

Question

我有一个与另一个实体有 OneToMany 关系的实体，当我坚持父实体时，我想确保子实体不包含重复项。

这是我一直在使用的类，discounts 集合不应包含给定客户的两个同名产品。

我有一个带有折扣集合的客户实体：

/**
 * @ORM\Entity
 */
class Client {

    /**
     * @ORM\Id
     * @ORM\Column(type="integer")
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    protected $id;

    /**
     * @ORM\Column(type="string", length=128, nullable="true")
     */
    protected $name;

    /**
     * @ORM\OneToMany(targetEntity="Discount", mappedBy="client", cascade={"persist"}, orphanRemoval="true")
     */
    protected $discounts;

}

/**
 * @ORM\Entity
 * @UniqueEntity(fields={"product", "client"}, message="You can't create two discounts for the same product")
 */
    class Discount {
        /**
         * @ORM\Id
         * @ORM\Column(type="string", length=128, nullable="true")
         */
        protected $product;

        /**
         * @ORM\Id
         * @ORM\ManyToOne(targetEntity="Client", inversedBy="discounts")
         * @ORM\JoinColumn(name="client_id", referencedColumnName="id")
         */
        protected $client;

        /**
         * @ORM\Column(type="decimal", scale=2)
         */
        protected $percent;
    }

如您所见，我尝试将UniqueEntity 用于 Discount 类，问题是验证器似乎只检查数据库上加载的内容（为空），所以当实体被持久化时，我得到一个“SQLSTATE [23000]：违反完整性约束”。

我已经检查了Collection 约束购买它似乎只处理字段集合，而不是实体。

还有 All 验证器，它允许您定义要应用于每个实体的约束，但不能应用于整个集合。

除了每次都写custom validator或Callback验证器之外，我需要知道整体是否存在实体集合约束，才能持久化到数据库。

Answer 1

我为此创建了一个自定义约束/验证器。

它使用“All”断言验证表单集合，并采用可选参数：属性的属性路径来检查实体是否相等。

（适用于 Symfony 2.1，要使其适应 Symfony 2.0，请检查答案的结尾）：

有关创建自定义验证约束的更多信息，请查看The Cookbook

约束：

#src/Acme/DemoBundle/Validator/constraint/UniqueInCollection.php
<?php

namespace Acme\DemoBundle\Validator\Constraint;

use Symfony\Component\Validator\Constraint;

/**
* @Annotation
*/
class UniqueInCollection extends Constraint
{
    public $message = 'The error message (with %parameters%)';
    // The property path used to check wether objects are equal
    // If none is specified, it will check that objects are equal
    public $propertyPath = null;
}

还有验证器：

#src/Acme/DemoBundle/Validator/constraint/UniqueInCollectionValidator.php
<?php

namespace Acme\DemoBundle\Validator\Constraint;

use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Form\Util\PropertyPath;

class UniqueInCollectionValidator extends ConstraintValidator
{

    // We keep an array with the previously checked values of the collection
    private $collectionValues = array();

    // validate is new in Symfony 2.1, in Symfony 2.0 use "isValid" (see below)
    public function validate($value, Constraint $constraint)
    {
        // Apply the property path if specified
        if($constraint->propertyPath){
            $propertyPath = new PropertyPath($constraint->propertyPath);
            $value = $propertyPath->getValue($value);
        }

        // Check that the value is not in the array
        if(in_array($value, $this->collectionValues))
            $this->context->addViolation($constraint->message, array());

        // Add the value in the array for next items validation
        $this->collectionValues[] = $value;
    }
}

在你的情况下，你会像这样使用它：

use Acme\DemoBundle\Validator\Constraints as AcmeAssert;

// ...

/**
 * @ORM\OneToMany(targetEntity="Discount", mappedBy="client", cascade={"persist"}, orphanRemoval="true")
 * @Assert\All(constraints={
 *     @AcmeAssert\UniqueInCollection(propertyPath ="product")
 * })
 */

对于 Symfony 2.0，将 validate 函数更改为：

public function isValid($value, Constraint $constraint)
{
        $valid = true;

        if($constraint->propertyPath){
            $propertyPath = new PropertyPath($constraint->propertyPath);
            $value = $propertyPath->getValue($value);
        }

        if(in_array($value, $this->collectionValues)){
            $valid = false;
            $this->setMessage($constraint->message, array('%string%' => $value));
        }

        $this->collectionValues[] = $value;

        return $valid

}

Answer 2

我无法使之前的答案在 symfony 2.6 上有效。由于 l 上的以下代码。 RecursiveContextualValidator 的 852 个，当 2 项相等时，它只在 validate 方法上执行一次。

if ($context->isConstraintValidated($cacheKey, $constraintHash)) {
    continue; 
} 

所以，这是我为处理原始问题所做的：

在实体上：

* @AcmeAssert\UniqueInCollection(propertyPath ="product")

代替

* @Assert\All(constraints={
*     @AcmeAssert\UniqueInCollection(propertyPath ="product")
* })

在验证器上：

public function validate($collection, Constraint $constraint){

    $propertyAccessor = PropertyAccess::getPropertyAccessor(); 

    $previousValues = array();
    foreach($collection as $collectionItem){
        $value = $propertyAccessor->getValue($collectionItem, $constraint->propertyPath);
        $previousSimilarValuesNumber = count(array_keys($previousValues,$value));
        if($previousSimilarValuesNumber == 1){
            $this->context->addViolation($constraint->message, array('%email%' => $value));
        }
        $previousValues[] = $value;
    }

}

代替：

public function isValid($value, Constraint $constraint)
{
    $valid = true;

    if($constraint->propertyPath){
        $propertyAccessor = PropertyAccess::getPropertyAccessor(); 
        $value = $propertyAccessor->getValue($value, $constraint->propertyPath);
    }

    if(in_array($value, $this->collectionValues)){
        $valid = false;
        $this->setMessage($constraint->message, array('%string%' => $value));
    }

    $this->collectionValues[] = $value;

    return $valid

}

Answer 3

对于 Symfony 4.3（仅测试版），您可以使用我的自定义验证器。 首选的使用方式是作为验证集合的注释：

use App\Validator\Constraints as App;

...

/**
 * @ORM\OneToMany
 *
 * @App\UniqueProperty(
 *     propertyPath="entityProperty"
 * )
 */
private $entities;

Julien 和我的解决方案之间的区别在于，我的约束是在经过验证的 Collection 上定义的，而不是在 Collection 本身的元素上定义的。

约束：

#src/Validator/Constraints/UniqueProperty.php
<?php


namespace App\Validator\Constraints;


use Symfony\Component\Validator\Constraint;

/**
 * @Annotation
 */
class UniqueProperty extends Constraint
{
    public $message = 'This collection should contain only elements with uniqe value.';
    public $propertyPath;

    public function validatedBy()
    {
        return UniquePropertyValidator::class;
    }
}

验证器：

#src/Validator/Constraints/UniquePropertyValidator.php
<?php

namespace App\Validator\Constraints;

use Symfony\Component\PropertyAccess\PropertyAccess;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Validator\Exception\UnexpectedTypeException;
use Symfony\Component\Validator\Exception\UnexpectedValueException;

class UniquePropertyValidator extends ConstraintValidator
{
    /**
     * @var \Symfony\Component\PropertyAccess\PropertyAccessor
     */
    private $propertyAccessor;

    public function __construct()
    {
        $this->propertyAccessor = PropertyAccess::createPropertyAccessor();
    }

    /**
     * @param mixed $value
     * @param Constraint $constraint
     * @throws \Exception
     */
    public function validate($value, Constraint $constraint)
    {
        if (!$constraint instanceof UniqueProperty) {
            throw new UnexpectedTypeException($constraint, UniqueProperty::class);
        }

        if (null === $value) {
            return;
        }

        if (!\is_array($value) && !$value instanceof \IteratorAggregate) {
            throw new UnexpectedValueException($value, 'array|IteratorAggregate');
        }

        if ($constraint->propertyPath === null) {
            throw new \Exception('Option propertyPath can not be null');
        }

        $propertyValues = [];
        foreach ($value as $key => $element) {
            $propertyValue = $this->propertyAccessor->getValue($element, $constraint->propertyPath);
            if (in_array($propertyValue, $propertyValues, true)) {
                $this->context->buildViolation($constraint->message)
                    ->atPath(sprintf('[%s]', $key))
                    ->addViolation();
            }

            $propertyValues[] = $propertyValue;
        }
    }
}

Answer 4

这是一个使用多个字段的版本，就像 UniqueEntity 一样。如果多个对象具有相同的值，则验证失败。

用法：

/**
* ....
* @App\UniqueInCollection(fields={"name", "email"})
*/
private $contacts;
//Validation fails if multiple contacts have same name AND email

约束类...

<?php
namespace App\Validator\Constraints;

use Symfony\Component\Validator\Constraint;

/**
 * @Annotation
 */
class UniqueInCollection extends Constraint
{
    public $message = 'Entry is duplicated.';
    public $fields;

    public function validatedBy()
    {
        return UniqueInCollectionValidator::class;
    }
}

验证器本身 ....

<?php

namespace App\Validator\Constraints;

use Symfony\Component\PropertyAccess\PropertyAccess;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Validator\Exception\UnexpectedTypeException;
use Symfony\Component\Validator\Exception\UnexpectedValueException;

class UniqueInCollectionValidator extends ConstraintValidator
{
    /**
     * @var \Symfony\Component\PropertyAccess\PropertyAccessor
     */
    private $propertyAccessor;

    public function __construct()
    {
        $this->propertyAccessor = PropertyAccess::createPropertyAccessor();
    }

    /**
     * @param mixed $collection
     * @param Constraint $constraint
     * @throws \Exception
     */
    public function validate($collection, Constraint $constraint)
    {
        if (!$constraint instanceof UniqueInCollection) {
            throw new UnexpectedTypeException($constraint, UniqueInCollection::class);
        }

        if (null === $collection) {
            return;
        }

        if (!\is_array($collection) && !$collection instanceof \IteratorAggregate) {
            throw new UnexpectedValueException($collection, 'array|IteratorAggregate');
        }

        if ($constraint->fields === null) {
            throw new \Exception('Option propertyPath can not be null');
        }

        if(is_array($constraint->fields)) $fields = $constraint->fields;
        else $fields = [$constraint->fields];


        $propertyValues = [];
        foreach ($collection as $key => $element) {
            $propertyValue = [];
            foreach ($fields as $field) {
                $propertyValue[] = $this->propertyAccessor->getValue($element, $field);
            }


            if (in_array($propertyValue, $propertyValues, true)) {

                $this->context->buildViolation($constraint->message)
                    ->atPath(sprintf('[%s]', $key))
                    ->addViolation();
            }

            $propertyValues[] = $propertyValue;
        }

    }
}