Is there a way to prevent circular occurence in Data?

[fd6130]

class FooData extends Data
{
      public function __constructor(
             public BarData $bar
      )
      {
      
      }

    public static function fromModel(Foo $model)
    {
          return new self(
             BarData::from($model->bar)
          );
    }

}

class BarData extends Data
{
      public function __constructor(
             public FooData $foo
      )
      {
      
      }

    public static function fromModel(Bar $model)
    {
          return new self(
             FooData::from($model->foo)
          );
    }

}

Update 2022-10-24

From the example above (or other similar situation) Foo and Bar model are bidirectional.

$foo = Foo::find(1);

FooData::from(foo); // will loop forever

It will keep looping until exhausted. How can I prevent it? Thanks.

[rubenvanassche]

In this case I would not use another from call in the custom creation methods since this will probably cause the loop. Manually creating the data object is the best option here.

If it still keeps looping, then take a look at the validation, and manually write out the rules or add a WithoutValidation attribute to the property, since our validation rules resolver is probably creating nested validation rules loops.

[fd6130]

I'm using the data for json response, not request. So i think validation doesn't help in my case. Perhaps lazy property is the way to prevent the loop?

[rubenvanassche]

Hi @fd6130,

I've added a circular dependency test:

laravel-data/tests/DataTest.php

Lines 2505 to 2536 in f5171d4

	/** @test */
	public function it_can_have_a_circular_dependency()
	{
	$data = CircData::from([
	'string' => 'Hello World',
	'ular' => [
	'string' => 'Hello World',
	'circ' => [
	'string' => 'Hello World',
	],
	],
	]);
	$this->assertEquals(
	new CircData('Hello World', new UlarData('Hello World', new CircData('Hello World', null))),
	$data
	);
	$this->assertEquals(
	[
	'string' => 'Hello World',
	'ular' => [
	'string' => 'Hello World',
	'circ' => [
	'string' => 'Hello World',
	'ular' => null,
	]
	]
	],
	$data->toArray()
	);
	}

And it is working at the moment, could you provide me a test which is broken so we can maybe fix the problem?

[fd6130]

In this case I would not use another from call in the custom creation methods since this will probably cause the loop. Manually creating the data object is the best option here.

I think you got a point there. But I'm not sure what "Manually creating the data object" mean. It is mean I should create the data object with array for that case?

Currently I can prevent it happens with lazy property. I will only include the property I wanted to display. I think this is the correct way right?

[rubenvanassche]

Well if that works than that's probably the best way to go! With manual creation I meant to to create the database object using new CircData(....) not suitable for all cases but sometimes it is not possible to use all the features of the data package in these kinds of edge cases.

[fd6130]

Thanks. I will mark this as answer.