library doctrine-read-only-hydrator

steevanb/doctrine-read-only-hydrator

Fast hydratation for read only purpose

, _(*1)

doctrine-read-only-hydrator

When you retrieve data with Doctrine, you can get an array with values, or a fully hydrated object., _(*2)

Hydration is a very slow process, who return same instance of entity if several hydrations have same entity to hydrate. It's fine when you want to insert / update / delete your entity. But when you just want to retrieve data without editing it (to show it in list for example), it's way to slow., _(*3)

If you want to really retrieve data from your database, and don't get UnitOfWork reference : with Doctrine hydration you can't. Each query will not hydrate a new entity with data taken in your query result, it will return the first hydrated entity, known by UnitOfWork., _(*4)

So, in case you don't need to modify your entity, you want to be really faster, or just retrieve data stored in your database, you can use SimpleObjectHydrator or ReadOnlyHydrator., _(*5)

This hydrated entities can't be persisted / flushed, because they are not registered in UnitOfwork to be faster., _(*6)

Nothing will be lazy loaded : to be faster, and because most of the time, you have to create a complete QueryBuilder, who return everything you need., _(*7)

Changelog, _(*8)

Benchmark

This table show simple benchmark results (time and memory_get_peak_usage()), with 30, 1000 and 5000 entities retrieved from a MySQL 5.7 database, PHP 5.6.23 and Doctrine 2.5.4., _(*9)

ArrayHydrator is used when you call $query->getArrayResult(), ObjectHydrator when you call $query->getResult(), $repository->findAll() or $repository->findBy()., _(*10)

SimpleObjectHydrator and ReadOnlyHydrator are provided with this lib, see example above., _(*11)

, _(*12)

You can see hydration process is really slow ! For 5 000 entities, Doctrine ObjectHydrator is 100x slower than the SQL request..., _(*13)

As expected, getArrayResult() is the fastest way to retrieve data. But, you have to work with array, so you can't use entity methods., _(*14)

ReadOnlyHydrator is 4x faster than Doctrine ObjectHydrator, and only 40% slower than ArrayHydrator (who is hard to use)., _(*15)

Is you want to be as fast as possible, but with an entity result instead of an array, SimpleObjectHydrator looks pretty good., _(*16)

SimpleObjectHydrator

• Hydrate your entity, with all selected fields in your QueryBuilder. If you try to access a non-loaded property, no exception will be throwned, you can call all accessors.
• No lazy loading will be executed.
• You can't persist or flush this entity.
• Usefull when you want to be faster than Doctrine ObjectHydrator (and a little little bit more than ReadOnlyHydrator), you don't want to insert / update this entity, but doesn't ensure you can't access non-loaded property.

ReadOnlyHydrator

• Hydrate a proxy of your entity, who throw an exception if you try to access a property who is not loaded by your QueryBuilder.
• No lazy loading will be executed.
• You can't persist or flush this entity.
• Usefull when you want to be faster than Doctrine ObjectHydrator, you don't want to insert / update this entity, and be "sure" any access to a non-loaded property will throw an exception.

Example

# Foo\Repository\BarRepository

use steevanb\DoctrineReadOnlyHydrator\Hydrator\ReadOnlyHydrator;

class BarRepository
{
    public function getReadOnlyUser($id)
    {
        return $this
            ->createQueryBuilder('user')
            ->select('user', 'PARTIAL comments.{id, comment}')
            ->join('user.comments', 'comments')
            ->where('user.id = :id')
            ->setParameter('id', $id)
            ->getQuery()
            ->getResult(ReadOnlyHydrator::HYDRATOR_NAME);
    }
}

Installation

composer require steevanb/doctrine-read-only-hydrator ^2.3

Symfony 2.x or 3.x integration

# app/AppKernel.php

class AppKernel extends Kernel
{
    public function registerBundles()
    {
        $bundles = [
            new steevanb\DoctrineReadOnlyHydrator\Bridge\ReadOnlyHydratorBundle\ReadOnlyHydratorBundle()
        ];
    }
}

Symfony 4.x or 5.x integration

# config/bundles.php

return [
    steevanb\DoctrineReadOnlyHydrator\Bridge\ReadOnlyHydratorBundle\ReadOnlyHydratorBundle::class => ['all' => true],
];

Manual integration

You need to register SimpleObjectHydrator and ReadOnlyHydrator to Doctrine\ORM\Configuration:, _(*17)

use steevanb\DoctrineReadOnlyHydrator\Hydrator\SimpleObjectHydrator;
use steevanb\DoctrineReadOnlyHydrator\Hydrator\ReadOnlyHydrator;

$configuration->addCustomHydrationMode(SimpleObjectHydrator::HYDRATOR_NAME, SimpleObjectHydrator::class);
$configuration->addCustomHydrationMode(ReadOnlyHydrator::HYDRATOR_NAME, ReadOnlyHydrator::class);

Integration with steevanb/doctrine-stats

steevanb/doctrine-stats add lots of statistics about Doctrine : number of mapped entities, number of lazy loaded entities, collapse and count same sql queries, show hydration time etc., _(*18)

If you use this lib, you have to add SimpleObjectHydrator and ReadOnlyHydrator hydration times :, _(*19)

# composer.json

{
    "extra": {
        "composer-overload-class-dev": {
            "steevanb\\DoctrineReadOnlyHydrator\\Hydrator\\SimpleObjectHydrator": {
                "original-file": "vendor/steevanb/doctrine-read-only-hydrator/Hydrator/SimpleObjectHydrator.php",
                "overload-file": "vendor/steevanb/doctrine-read-only-hydrator/ComposerOverloadClass/Hydrator/SimpleObjectHydrator.php"
            },
            "steevanb\\DoctrineReadOnlyHydrator\\Hydrator\\ReadOnlyHydrator": {
                "original-file": "vendor/steevanb/doctrine-read-only-hydrator/Hydrator/ReadOnlyHydrator.php",
                "overload-file": "vendor/steevanb/doctrine-read-only-hydrator/ComposerOverloadClass/Hydrator/ReadOnlyHydrator.php"
            }
        }
    }
}