DTO - PHP Data Transfer Object

A PHP implementation of the Data Transfer Object pattern (https://martinfowler.com/eaaCatalog/dataTransferObject.html).
The Data Transfer Object allows for public properties with forced validation of their data types.

This implementation supports all of PHP's eight primitive data types:

• String
• Integer
• Double (or by PHP-implementation floating point numbers)
• Boolean
• Array
• Object
• Null
• Resource

As well as forced boolean values of:

• True
  and
• False

Install

Via Composer

$ composer require anfischer/dto

Usage

The DTO class can be used to generate generic Data Transfer Objects which does not enforce initializing type, but guaranties strict types for initialized properties (e.g. a property which is first initialized as string can not be changed to integer later)

use Anfischer\Dto\Dto;

class GenericDataTransferObject extends Dto
{
    protected $someProperty;
    protected $anotherProperty;
}

$dto = new GenericDataTransferObject;
$dto->someProperty = 1;
$dto->anotherProperty = null;

// ERROR - throws InvalidTypeException since type is changed from integer to string
$dto->someProperty = 'foo';

// OK - since it was first initialized as null
$dto->anotherProperty = 'foo';

The DTO class also allows for generating type hinted Data Transfer Objects.
When forcing types properties can not be initialized with other types than defined for the properties (e.g. a property which is defined as string can not be initialized as integer)

use Anfischer\Dto\Dto;

class TypeHintedDataTransferObject extends Dto
{
    protected $stringProperty;
    protected $integerProperty;
    
    public function getPropertyType($property): string
    {
        switch ($property) {
            case 'stringProperty':
                return 'string';
            case 'integerProperty':
                return 'integer';
        }
    }
}

$dto = new TypeHintedDataTransferObject;

$dto->stringProperty = 'foo';
$dto->integerProperty = 1;

// ERROR - throws InvalidTypeException since type has to be initialized as string
$dto->stringProperty = 1;

// ERROR - throws InvalidTypeException since type has to be initialized as integer
$dto->integerProperty = 'foo';

Finally, the DTO class allows for generating type hinted Data Transfer Objects with mixed types.

use Anfischer\Dto\Dto;

class TypeHintedDataTransferObject extends Dto
{
    protected $mixedProperty;
    
    public function getPropertyType($property): string
    {
        switch ($property) {
            case 'mixedProperty':
                return 'string|integer|array';
        }
    }
}

$dto = new MixedTypeHintedDataTransferObject;

$dto->mixedProperty = 'foo';
$dto->mixedProperty = 1;
$dto->mixedProperty = ['foo', 'bar', 'baz'];

// ERROR - throws InvalidTypeException since type has to be either string, integer or array
$dto->mixedProperty = 1.1;

// ERROR - throws InvalidTypeException since type has to be either string, integer or array
$dto->mixedProperty = false;

Change log

Please see CHANGELOG for more information on what has changed recently.

Testing

$ composer test

Contributing

Please see CONTRIBUTING and CODE_OF_CONDUCT for details.

Security

If you discover any security related issues, please email [email protected] instead of using the issue tracker.

Credits

• Andreas Fischer
• All Contributors

License

The MIT License (MIT). Please see License File for more information.