Question

The Problem:

I am working on a WordPress Symfony bundle and creating entities for it.

I have a Comment entity, and $comment->user is mapped to an User entity.

However WordPress use 0 to represent a guest user. It cause a lots of problems in Doctrine because the user with id zero never exist. It cause the following issues:

• $comment->getUser() might throw an entity not found exception when the row’s user_id is 0.
• $comment->setUser() doesn’t work because you can not use null to repensent guest (should use 0), and you cannot use new User(0) neither.

The Question:

By default, the following code would save null to user_id column in database:

$comment->setUser(null);

Is it possible to make Doctrine save 0 (instead of null) to the user_id column?

Or even better, can I interchange 0 and null when dealing with the user_id column?

Thank you for your time.

Test Cases:

// if a guest posted a comment, pass null to setUser()
// although the actual value will be saved to user_id column is 0
$guestComment->setUser(null);

// if a comment was posted by a guest, getUser() should return null
// although the actual value returned by user_id column is 0
$guestComment->getUser(); // return null

// if a member posted a comment, pass a User entity to setUser()
$memberComment->setUser(new User());

// if a comment was posted by a member, getUser() should return the User entity
$guestComment->getUser(); // return User entity.

Direction:

I am looking at creating a custom mapping types
http://docs.doctrine-project.org/projects/doctrine-dbal/en/latest/reference/types.html

Answer 1

I turn out fixed the problem by creating a custom type:

https://github.com/kayue/WordpressBundle/blob/master/Types/WordPressIdType.php

<?php

/**
 * Datatype for WordPress's IDs
 *
 * WordPress use 0 to represent a guest user. It cause a lots of problems
 * in Doctrine because the user with id zero never exist. This datatype
 * convert 0 to null, make life easier.
 */

namespace Hypebeast\WordpressBundle\Types;

use Doctrine\DBAL\Types\Type;
use Doctrine\DBAL\Types\BigIntType;
use Doctrine\DBAL\Platforms\AbstractPlatform;

class WordPressIdType extends BigIntType
{
    const NAME = 'wordpressid';

    public function convertToPHPValue($value, AbstractPlatform $platform)
    {
        if($value === 0) {
            return null;
        }

        return $value;
    }

    public function convertToDatabaseValue($value, AbstractPlatform $platform)
    {
        if($value === null) {
            return 0;
        }

        return $value;
    }

    public function getName()
    {
        return self::NAME;
    }
}