[OpenAPI/Hydra] Validation error schema should be generated

[alanpoulain]

Description

In OpenApiFactory, the schema is not generated for the validation error (422):

core/src/OpenApi/Factory/OpenApiFactory.php

Line 227 in e649fa1

$responses['422'] = new Model\Response('Unprocessable entity');

It would be nice to add it at least for Hydra.
Hydra normalizes the validation error like this:

core/src/Core/Hydra/Serializer/ConstraintViolationListNormalizer.php

Lines 46 to 50 in e649fa1

	'@context' => $this->urlGenerator->generate('api_jsonld_context', ['shortName' => 'ConstraintViolationList']),
	'@type' => 'ConstraintViolationList',
	'hydra:title' => $context['title'] ?? 'An error occurred',
	'hydra:description' => $messages ? implode("\n", $messages) : (string) $object,
	'violations' => $violations,

One way to implement it would be to add a new schema type, like TYPE_VALIDATION_ERROR here:

core/src/Core/JsonSchema/Schema.php

Lines 30 to 31 in e649fa1

	public const TYPE_INPUT = 'input';
	public const TYPE_OUTPUT = 'output';

And handle this new type in this method:

core/src/Core/Hydra/JsonSchema/SchemaFactory.php

Line 73 in e649fa1

public function buildSchema(string $className, string $format = 'jsonld', string $type = Schema::TYPE_OUTPUT, ?string $operationType = null, ?string $operationName = null, ?Schema $schema = null, ?array $serializerContext = null, bool $forceCollection = false): Schema

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.