New in Symfony 5.4: Nested Validation Attributes

Contributed by Alexandre Daubois in #41994.

In Symfony 5.2 we added a feature to define validation constraints as PHP attributes. Attributes were very recent at that time, because they had just been added to PHP 8.0. The only caveat was that you couldn't nest PHP attributes, so you couldn't use them with constraints such as AtLeastOneOf and Collection. Thankfully, PHP 8.1, released on November 25, 2021, adds support for nested attributes. That's why in Symfony 5.4 you'll be able to use PHP attributes to define all existing constraints, without any exemption. The trick that enables this feature is to use the new keyword to create the nested attribute:

    1

2 3 4 5 6 7

[Attribute1(new SubAttribute1())]

[Attribute2([new SubAttribute2(), new SubAttribute3()])]

[Attribute3(someProperty: new SubAttribute4())]

class SomeClass { // ... }

This is how it looks in practice when using Symfony Validator constraints in a complex example:

    1

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 use Symfony\Component\Validator\Constraints as Assert;

class SomeClass {

[Assert\All([

    new Assert\NotNull(),
    new Assert\Range(min: 3),
])]
#[Assert\Collection(
    fields: [
        'foo' => [
            new Assert\NotNull(),
            new Assert\Range(min: 3),
        ],
        'bar' => new Assert\Range(min: 5),
        'baz' => new Assert\Required([new Assert\Email()]),
        'qux' => new Assert\Optional([new Assert\NotBlank()]),
    ],
    allowExtraFields: true
)]
private $property1;

#[Assert\AtLeastOneOf(
    constraints: [
        new Assert\NotNull(),
        new Assert\Range(min: 3),
    ],
    message: 'foo',
    includeInternalMessages: false,
)]
#[Assert\Sequentially([
    new Assert\NotBlank(),
    new Assert\Range(min: 5),
])]
private $property2;

// ...

}

                Sponsor the Symfony project.

http://feedproxy.google.com/~r/symfony/blog/~3/O6xhOezW6nk/new-in-symfony-5-4-nested-validation-attributes

Created 4y | Nov 5, 2021, 8:20:05 AM


Login to add comment

Other posts in this group

A Week of Symfony #965 (June 23–29, 2025)

This week, Symfony 6.4.23, 7.2.8 and 7.3.1 maintenance versions were released. Meanwhile, the upcoming Symfony 7.4 version continued adding new features such as better controller helpers, more precisi

Jun 29, 2025, 9:10:15 AM | Symfony
Symfony 6.4.23 released

Symfony 6.4.23 has just been released. Read the Symfony upgrade guide to learn more about upgrading Symfony and use the SymfonyInsight upgrade reports to detect the code you will need to change in you

Jun 28, 2025, 9:50:15 AM | Symfony
Symfony 7.2.8 released

Symfony 7.2.8 has just been released. Read the Symfony upgrade guide to learn more about upgrading Symfony and use the SymfonyInsight upgrade reports to detect the code you will need to change in your

Jun 28, 2025, 9:50:15 AM | Symfony
Symfony 7.3.1 released

Symfony 7.3.1 has just been released. Read the Symfony upgrade guide to learn more about upgrading Symfony and use the SymfonyInsight upgrade reports to detect the code you will need to change in your

Jun 28, 2025, 9:50:14 AM | Symfony
A Week of Symfony #964 (June 16–22, 2025)

This week, development activity was intense, with many bug fixes in the maintained branches, numerous deprecation removals in the 8.0 branch, and new features added to the 7.4 branch, including tighte

Jun 22, 2025, 8:10:05 AM | Symfony
SymfonyOnline June 2025: Speakers, Stats & Replays!

Thank you for joining us at SymfonyOnline June 2025!

What a great edition of SymfonyOnline we’ve just wrapped up! 🎉

We were thrilled to welcome 300 participants from 35 different countries—a

Jun 18, 2025, 8:50:17 AM | Symfony
A Week of Symfony #963 (June 9–15, 2025)

This week, Symfony celebrated the SymfonyOnline June 2025 conference with great success. Meanwhile, development efforts focused on improving invokable commands for the upcoming Symfony 7.4 version. Th

Jun 15, 2025, 9:10:09 AM | Symfony