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Fundamentals

Types​

In PHP AutoMapper, the types of class properties play a crucial role in how mapping is performed. The types are determined using the Symfony PropertyInfo component. This means you can use PHP type hints or PHPDoc type hints to define the types of your properties.

Here's an example:

class SourceClass {
    /**
     * @var string[]
     */
    private array $titles;
}

In the above example, the titles member is a typed array of strings.

Default Mapping​

By default, AutoMapper will automatically map the values if the source and destination types match. For instance, if a member in the source class is of type string and the corresponding member in the destination class is also of type string, AutoMapper will automatically map the value without further configuration.

Customizing Type Conversion​

In cases where the source and destination types do not match (e.g., mapping a string to an int), a custom mapping is required. This can be achieved using the forMember method and providing a custom mapping function.

Here's an example:

class SourceClass {
    public string $age;
}

class DestinationClass {
    public int $age;
}

$config = new MapperConfiguration(fn (Config $config) => $config
    ->createMap(SourceClass::class, DestinationClass::class)
    ->createMap('string', 'int')
    ->convertUsing(fn (string $source, ResolutionContextInterface $context): int => intval($source))
);

In this example, we're mapping the age member of SourceClass (which is a string) to the age member of DestinationClass (which is an int). The custom mapping function converts the string to an integer before mapping.

Members​

In PHP AutoMapper, properties of classes are referred to as "members". These members are the key elements that are mapped from source to destination classes.

PHP AutoMapper uses the Symfony PropertyAccess component to read and write member values. This component allows AutoMapper to access public, protected, and private properties using getter and setter methods. This means that even if your class properties are not public, AutoMapper can still map them as long as there are appropriate getter and setter methods available.

Default Mapping​

By default, AutoMapper maps members with matching names between the source and destination classes. This means if your source class has a property named title, and your destination class also has a property named title, AutoMapper will automatically map the value of title from the source to the destination.

class SourceClass {
    public string $title;
}

class DestinationClass {
    public string $title;
}

$config = new MapperConfiguration(fn (Config $config) => $config
    ->createMap(SourceClass::class, DestinationClass::class)
);

$autoMapper = $config->createMapper();
$destination = $autoMapper->map(new SourceClass(), DestinationClass::class);

In the above example, the title member of SourceClass will be mapped to the title member of DestinationClass.

Customizing Member Mapping​

You can customize how individual members are mapped using the forMember method. The mapping configuration is defined on the destination type. Here's an example:

$config = new MapperConfiguration(fn (Config $config) => $config
    ->createMap(SourceClass::class, DestinationClass::class)
    ->forMember(
        'title',
        fn (Options $opts) => $opts->mapFrom(
            fn (SourceClass $source) => $source->title . ' custom'
        )
    )
);

In this example, we're appending the string ' custom' to the title member of SourceClass when it's mapped to DestinationClass.