Custom base entity in Symfony 4

Question

I am using Symfony 4 and with Doctrine where I have entities which have the same common attributes such as createdWhen, editedWhen, ...

What i would like to do is this:

Defining a kind of base entity that holds these common attributes and implements the setter and getter. And many entities which inherit from that base entity. The database fields should all be defined in the table of the respective sub entity (no super table or the like should be created in the db).

Example:

/**
 * @ORM\Entity(repositoryClass="App\Repository\BaseRepository")
 */
class Base
{
    /**
     * @ORM\Id()
     * @ORM\GeneratedValue()
     * @ORM\Column(type="integer")
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=127, nullable=true)
     */
    private $createdWhen;

    // Getter and setter
    ...
}


/**
 * @ORM\Entity(repositoryClass="App\Repository\PersonRepository")
 */
class Person extends Base
{
    /**
     * @ORM\Column(type="string", length=127, nullable=true)
     */
    private $name;

    // Getter and setter
    ...
}

/**
 * @ORM\Entity(repositoryClass="App\Repository\CarRepository")
 */
class Car extends Base
{
    /**
     * @ORM\Column(type="string", length=127, nullable=true)
     */
    private $brand;

    // Setter and getter
    ...
}

This should create the tables "person" and "car" (each with id, created_when) but no table base.

I would still like to be able to use the bin/console make:migration for updating the database schema.

Is this kind of approach possible with Symfony 4? If yes how would I define the entities and what do I have to change in terms of configuration, etc.?

Eventually you could use traits. [Here](https://www.sitepoint.com/using-traits-doctrine-entities/) is a short tutorial. — cezar, Mar 07 '19 at 09:14
@cezar Very interesting approach! That solves the little disadvantage with the console tool... And it could help with another question: to order the fields in a way I like to, no matter if they are in parent or base class. Thank you! — Martin Newman, Mar 08 '19 at 14:37

score 7 · Accepted Answer · answered Mar 06 '19 at 13:34

7

You are looking for entity inheritance

Rewrite your code like so

/** @MappedSuperclass */
class Base
{
...
}

In fact, this is a part of Doctrine, here is what an official documentation says

A mapped superclass is an abstract or concrete class that provides persistent entity state and mapping information for its subclasses, but which is not itself an entity. Typically, the purpose of such a mapped superclass is to define state and mapping information that is common to multiple entity classes.

answered Mar 06 '19 at 13:34

Majesty

2,097
5
24
55

Yeah! That is what I am looking for! I will try it out if it works with the console tools.. – Martin Newman Mar 06 '19 at 13:43
I have to alter the created entity a bit after creating an entity named 'Test' by running php bin/console make:entity as there seems to be no options to use a super class. It creates an id attribute automatically. But in general it works... Thank you! – Martin Newman Mar 06 '19 at 14:03

Custom base entity in Symfony 4

1 Answers1