MapInputName attribute bug/improvement

[Ruben10-R]

✏️ Describe the bug
When creating a data object, there can be a mismatch between input coming from a request and input coming from a model. Spatie Laravel Data currently has no way to differentiate whether a data object is being filled from a request or from a model, and how mapping should be handled in each case.

Example:

CandidateData->firstName
ApiCandidate->firstname (model)
CandidateRequest->first_name (request input)

Spatie Data offers #[MapInputName], but this cannot differentiate between firstname (model) and first_name (request). Manual mapping for each field is possible but becomes cumbersome when many fields and data objects need mapping. Also the

↪️ To Reproduce

use Spatie\LaravelData\Attributes\MapInputName;
use Spatie\LaravelData\Data;

#[MapName(SnakeCaseMapper::class)]
abstract class AbstractApiData extends Data
{
// Simplified abstract class
}

class CandidateData extends AbstractApiData
{
#[MapInputName('firstname')]
public ?string $firstName;

#[MapInputName('lastname')]
public ?string $lastName;

public function __construct(?string $firstName, ?string $lastName)
{
    $this->firstName = $firstName;
    $this->lastName = $lastName;
}

}

// Example of request data
$requestData = [
'first_name' => 'John',
'last_name' => 'Doe',
];

// This will not map 'first_name' to 'firstName' correctly for model data
dd(CandidateData::from($requestData));

✅ Expected behavior
The first_name from the request should map correctly to CandidateData->firstName, while firstname from the model should also map correctly. It should be possible to define both mappings using a single attribute or optional parameters.

🖥️ Versions

Laravel: 12.x
Laravel Data (Spatie): 4.x
PHP: 8.4

[rubenvanassche]

Hi @Ruben10-R,

Yeah this is on my list for a v5 release, yet I have no idea how we'll build a simple API to create such a thing. Feel free to provide some ideas!

[RubenR-302]

I know this isn’t the full solution for detecting whether something comes from the request or the model, but this approach could already solve our problem.

With something like this:

#[MapInputName(request: 'first_name', model: 'firstname')]
public ?string $firstName;

…we could easily see that first_name comes from the request, and confirm that the mapping works correctly.

Additionally, it might be nice to make MapInputName a bit smarter — for example, if we’re using a SnakeCaseMapper, it could automatically take that into account and infer the request input name based on the mapper configuration.