Conditional Mapping

Ignoring a property is a good way to exclude it from the mapping process, but sometimes you may want to map a property conditionally. This can be done using the #[MapTo] or #[MapFrom] attributes with the if argument.

The argument may accept several types of values:

Expression language

You can use the Symfony Expression Language to define the condition. In this context the source object is available as source and the context array is available as context.

class Source
{
    public bool $propertyIsValid = true;

    #[MapTo(if: 'source.propertyIsValid and (context["custom_key"] ?? false) == true')]
    public $property;
}

If you use the Bundle version of the AutoMapper, there is also additional functions available.

Note

In standalone mode we do not provide any functions to the expression language. However we are interested in adding some functions to the expression language in the future. If you have some use cases that you would like to see covered, please open an issue on the GitHub repository.

PHP function

You can use a php function to define the condition. This function must return a boolean value.

class Source
{
    #[MapTo(if: 'boolval')]
    public string $property = '';
}

Warning

If the PHP function need more arguments than the source object and the context array, it will throw an exception.

Static callback

You can use a static callback to define the condition.

class Source
{
    public bool $propertyIsValid = true;

    #[MapTo(if: [self::class, 'isPropertyValid'])]
    public $property;

    public static function isPropertyValid(Source $source, array $context): bool
    {
        return $source->propertyIsValid && ($context['custom_key'] ?? false) === true;
    }
}

The static callback can accept the source object and the context array as arguments.

Dynamic callback

You can also reference a method of the object declaring the attribute to define the condition.

class Source
{
    public bool $propertyIsValid = true;

    #[MapTo(if: 'isPropertyValid')]
    public $property;

    public function isPropertyValid(): bool
    {
        return $this->propertyIsValid;
    }
}

The dynamic callback can accept the source object and the context array as arguments.