Symfony quickstart

composer require --dev "studio-design/gesso:^2.0" symfony/http-foundation symfony/http-kernel

Register the extension in phpunit.xml. Gesso finds spec files through the PHPUnit extension, not a Symfony bundle:

<extensions>
    <bootstrap class="Studio\Gesso\PHPUnit\OpenApiCoverageExtension">
        <parameter name="spec_base_path" value="openapi"/>
        <parameter name="specs" value="petstore"/>
    </bootstrap>
</extensions>

Mix Studio\Gesso\Symfony\OpenApiAssertions into a PHPUnit or WebTestCase class and name the spec with #[OpenApiSpec] (or override openApiSpec()):

use PHPUnit\Framework\TestCase;
use Studio\Gesso\Attribute\OpenApiSpec;
use Studio\Gesso\Symfony\OpenApiAssertions;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

#[OpenApiSpec('petstore')]
class PetsApiTest extends TestCase
{
    use OpenApiAssertions;

    public function test_pets_index(): void
    {
        $request = Request::create('/pets', 'GET');
        $response = new Response('[{"id":1,"name":"Fido"}]', 200, [
            'Content-Type' => 'application/json',
        ]);

        $this->assertResponseMatchesOpenApiSchema($request, $response);
    }
}

The trait adds three assertions: assertResponseMatchesOpenApiSchema($request, $response), assertRequestMatchesOpenApiSchema($request), and assertClientMatchesOpenApiSchema($client), which runs both against the last client call.

Run the CI-tested examples/symfony fixture:

composer test

For a full application, call assertClientMatchesOpenApiSchema($client) after KernelBrowser::request(). Both forms record coverage.