Schema wrongly absorbs property from another schema

[coriolanweihrauch]

Scenario:

1. a schema is declared above a child_class
2. child_class extends parent_class
3. another schema is declared above parent_class

Unexpected result: the property of the parent_class schema is merged into the schema of the child_class

Example code:

<?php

namespace App\Http\Controllers;

use OpenApi\Attributes as OA;

#[OA\Schema(
    schema: "UsefulSchema",
    properties: [
        new OA\Property(property: "good", type: "string", example: "expected to display"),
    ],
    type: "object",
)]
class TestController extends Parent_class
{
    #[OA\Get(
        path: "/url",
        summary: "controller",
        requestBody: new OA\RequestBody(
            content: new OA\JsonContent(
                ref: "#/components/schemas/UsefulSchema"
            )
        ),
        responses: [
            new OA\Response(
                response: 200,
                description: "Successful response",
            ),
        ]
    )]
    public function action()
    {
    }
}

#[OA\Schema(
    schema: "BuggySchema",
    properties: [
        new OA\Property(property: "bug", type: "string", example: "should not appear"),
    ],
    type: "object",
)]
class Parent_class
{
}

Expected result

Get /url
Request body: application/json
Example Value

{
  "good": "expected to display"
}

Actual result

Get /url
Request body: application/json
Example Value

{
  "bug": "should not appear",
  "good": "expected to display"
}

Workaround

Do not declare schemas above classes and move them into the body

[DerManoMann]

Schemas and (to a degree Operations) follow PHP inheritance rules. This includes parent class(es) (as in your example), but also interfaces and traits.

It is actually a feature in swagger-php that allows to compose Schema objects using regular PHP inheritance.