README

A Symfony bundle to enable value objects and DTOs to normalize and denormalize themselves through implementing simple interfaces that normalize to scalar values and denormalize themselves from scalar values (string, int, float, bool and array). Adding this kind of logic to the classes themselves might be considered a bad practice, but depending on the use case it will actually be better due to the fact that the data structure and the normalization need to be changed together.

The name implies that the value objects and DTOs are self-aware in the sense that they know how to normalize and denormalize themselves and that they are self-aware enough to do so 🙂

As it's a central part of an application, it's tested thoroughly (including mutation testing).

Installation and configuration

Install package through composer:

composer require digital-craftsman/self-aware-normalizers

Optionally, you can add a self-aware-normalizers.php file to your config/packages directory to configure the bundle to automatically register all custom doctrine types in one or multiple directories:

<?php

declare(strict_types=1);

use Symfony\Config\SelfAwareNormalizersConfig;

return static function (SelfAwareNormalizersConfig $selfAwareNormalizersConfig) {
    $selfAwareNormalizersConfig->doctrineTypeDirectories([
        '%kernel.project_dir%/src/Doctrine',
    ]);
};

Usage

Normalizers

To make the normalization process easier, there are the following normalizers included:

• StringNormalizableNormalizer
• IntNormalizableNormalizer
• FloatNormalizableNormalizer
• BoolNormalizableNormalizer
• ArrayNormalizableNormalizer

Additionally, there is an interface for each of the normalizers. Every class that implements one of the interfaces, will be automatically normalized to the respected type. This means putting the logic of how serialization of a class works within the class. That's not really seen as a good practice. In my experience, the data structure and the normalization need to be changed together. So, I like it better to have both in one place. I've used this approach in multiple large scale projects for years and haven't had a single issue with it yet. But your mileage may vary.

Doctrine types

When using the normalizers, you can also use the same logic for doctrine types. Simply create a new doctrine type extending of one of the following types and register them:

• StringNormalizableType
• StringEnumType
• IntNormalizableType
• FloatNormalizableType
• BoolNormalizableType
• ArrayNormalizableType

As an added bonus, this makes sure, that the structure is always the same no matter if you're using Doctrine to read from the data or a normalizer.

Additional documentation

• Changelog
• Upgrade guide