The `Source` class is a new entry point for sources that are not plain
array or iterable. It allows accessing other features like camel-case
keys or custom paths mapping in a convenient way.
It should be used as follows:
```php
$source = \CuyZ\Valinor\Mapper\Source\Source::json($jsonString)
->camelCaseKeys()
->map([
'towns' => 'cities',
'towns.*.label' => 'name',
]);
$result = (new \CuyZ\Valinor\MapperBuilder())
->mapper()
->map(SomeClass::class, $source);
```
It is now mandatory to explicitly register custom constructors —
including named constructors — that can be used by the mapper. The
former automatic registration of named constructor feature doesn't
work anymore.
BREAKING CHANGE: existing code must list all named constructors that
were previously automatically used by the mapper, and registerer them
using the method `MapperBuilder::registerConstructor()`.
The method `MapperBuilder::bind()` has been deprecated, the method above
should be used instead.
```php
final class SomeClass
{
public static function namedConstructor(string $foo): self
{
// …
}
}
(new \CuyZ\Valinor\MapperBuilder())
->registerConstructor(
SomeClass::namedConstructor(...),
// …or for PHP < 8.1:
[SomeClass::class, 'namedConstructor'],
)
->mapper()
->map(SomeClass::class, [
// …
]);
```
This modifier can be used to change paths in the source data using a dot
notation.
The mapping is done using an associative array of path mappings. This
array must have the source path as key and the target path as value.
The source path uses the dot notation (eg `A.B.C`) and can contain one
`*` for array paths (eg `A.B.*.C`).
```php
final class Country
{
/** @var City[] */
public readonly array $cities;
}
final class City
{
public readonly string $name;
}
$source = new \CuyZ\Valinor\Mapper\Source\Modifier\PathMapping([
'towns' => [
['label' => 'Ankh Morpork'],
['label' => 'Minas Tirith'],
],
], [
'towns' => 'cities',
'towns.*.label' => 'name',
]);
// After modification this is what the source will look like:
[
'cities' => [
['name' => 'Ankh Morpork'],
['name' => 'Minas Tirith'],
],
];
(new \CuyZ\Valinor\MapperBuilder())
->mapper()
->map(Country::class, $source);
```
The method `MapperBuilder::infer()` can be used to infer an
implementation for a given interface.
The callback given to this method must return the name of a class that
implements the interface. Any arguments can be required by the callback;
they will be mapped properly using the given source.
```php
$mapper = (new \CuyZ\Valinor\MapperBuilder())
->infer(UuidInterface::class, fn () => MyUuid::class)
->infer(SomeInterface::class, fn (string $type) => match($type) {
'first' => FirstImplementation::class,
'second' => SecondImplementation::class,
default => throw new DomainException("Unhandled type `$type`.")
})->mapper();
// Will return an instance of `FirstImplementation`
$mapper->map(SomeInterface::class, [
'type' => 'first',
'uuid' => 'a6868d61-acba-406d-bcff-30ecd8c0ceb6',
'someString' => 'foo',
]);
// Will return an instance of `SecondImplementation`
$mapper->map(SomeInterface::class, [
'type' => 'second',
'uuid' => 'a6868d61-acba-406d-bcff-30ecd8c0ceb6',
'someInt' => 42,
]);
interface SomeInterface {}
final class FirstImplementation implements SomeInterface
{
public readonly UuidInterface $uuid;
public readonly string $someString;
}
final class SecondImplementation implements SomeInterface
{
public readonly UuidInterface $uuid;
public readonly int $someInt;
}
```
Using variadic parameters is now handled properly by the library,
meaning the following example will run:
```php
final class SomeClass
{
/** @var string[] */
private array $values;
public function __construct(string ...$values)
{
$this->values = $values;
}
}
(new \CuyZ\Valinor\MapperBuilder())
->mapper()
->map(SomeClass::class, ['foo', 'bar', 'baz']);
```
The method `MapperBuilder::bind()` can be used to define a custom way to
build an object during the mapping.
The return type of the callback will be resolved by the mapping to know
when to use it.
The callback can take any arguments, that will automatically be mapped
using the given source. These arguments can then be used to instantiate
the object in the desired way.
Example:
```php
(new \CuyZ\Valinor\MapperBuilder())
->bind(function(string $string, OtherClass $otherClass): SomeClass {
$someClass = new SomeClass($string);
$someClass->addOtherClass($otherClass);
return $someClass;
})
->mapper()
->map(SomeClass::class, [
// …
]);
```
Inferring object unions and named constructor are now done using the
same algorithm — in class `ObjectBuilderFilterer` — which is called from
a unique entry point in `ClassNodeBuilder`.
An object may have several ways of being created — in such cases it is
common to use so-called named constructors, also known as static factory
methods. If one or more are found, they can be called during the mapping
to create an instance of the object.
What defines a named constructor is a method that:
1. is public
2. is static
3. returns an instance of the object
4. has one or more arguments
```php
final class Color
{
/**
* @param int<0, 255> $red
* @param int<0, 255> $green
* @param int<0, 255> $blue
*/
private function __construct(
public readonly int $red,
public readonly int $green,
public readonly int $blue
) {}
/**
* @param int<0, 255> $red
* @param int<0, 255> $green
* @param int<0, 255> $blue
*/
public static function fromRgb(
int $red,
int $green,
int $blue,
): self {
return new self($red, $green, $blue);
}
/**
* @param non-empty-string $hex
*/
public static function fromHex(string $hex): self
{
if (strlen($hex) !== 6) {
throw new DomainException('Must be 6 characters long');
}
/** @var int<0, 255> $red */
$red = hexdec(substr($hex, 0, 2));
/** @var int<0, 255> $green */
$green = hexdec(substr($hex, 2, 2));
/** @var int<0, 255> $blue */
$blue = hexdec(substr($hex, 4, 2));
return new self($red, $green, $blue);
}
}
```
This abstraction layer was not useful, so it is removed to simplify the
API around `ClassDefinition`.
A new method `ClassDefinition::type()` is also added, giving access to
the `ClassType` instance when working with a class definition.
This also brings `TreeMapper#map()` closer to PHPStorm support, whilst
still benefiting from more precise `vimeo/psalm:4.18.x` types thanks to
the conditional return specification.
Ref: https://github.com/CuyZ/Valinor/pull/59#discussion_r782362428
