[MODM-123] Single Collection Inheritance : hydration won't work properly

Wed, 23 Feb 2011 23:46:37 +0000

There is still a problem with Single Collection Inheritance.

Please consider the following code :

 
/**
 * @Document(db="forum", collection="Items")
 * @InheritanceType("SINGLE_COLLECTION")
 * @DiscriminatorField(fieldName="type")
 * @DiscriminatorMap({0="Items", 1="Stuffs"})
*/
class Items
{
    /**
     *
     * @id
     */
    public $id;

    /**
     * @String
     */
    public $title;
}



/**
 * @Document(db="forum", collection="Items")
*/
class Stuffs extends Items
{
    
    /**
     *
     * @id
     */
    public $id;

    /**
     * @String
     */
    public $stuffname;

}

$a = new Stuffs();
$a->stuffname = 'TTT';
$dm->persist($a);
$dm->flush();

Resulting in the database with :

 
{
   "_id": ObjectId("4d5dd082b53251b84e000000"),
   "stuffname": "TTT",
   "type": 1 
}

Now if I do :

 
$result = $dm->find('Items', $a->id);

then $result is an instance of Stuffs

But if I try :

 
$result = $dm->find('Items', '4d5dd082b53251b84e000000');

then $result is an instance of Items

Note that '$a->id' is a string, the same string containing '4d5dd082b53251b84e000000', so :

 
$result = $dm->find('Items', $a->id); 
$result = $dm->find('Items', '4d5dd082b53251b84e000000');

are semantically equivalent. It seems however that hydration would ignore the DiscriminatorMap in the second example.

However If you do :

 
$result = $dm->find('Stuffs', '4d5dd082b53251b84e000000');

You'll get a Stuffs as a result.

Now I tried to find a workaround when you don't know the type of the returned object. My initial intention was to first fetch a document with :

 
$result = $dm->find('Items', '4d5dd082b53251b84e000000');

Then I'm testing a property in the objet to see if it's a Stuffs, if it is, I tried an new :

 
$result = $dm->find('Stuffs', '4d5dd082b53251b84e000000');

In order to fetch a Stuffs. But ... I still get a *Items"!

So basically, if you do :

 
$result = $dm->find('Stuffs', '4d5dd082b53251b84e000000');

You get a Stuffs. But if you do :

 
$dm->find('Items', '4d5dd082b53251b84e000000'); 
$result = $dm->find('Stuffs', '4d5dd082b53251b84e000000');

You get a Items!

Doctrine Project

[MODM-123] Single Collection Inheritance : hydration won't work properly