FastAPI app with `separate_input_output_schemas` disabled excludes computed fields on Pydantic models from OpenAPI output

[tiangolo]

Adding the issue for completeness.

Solved in #13207

Discussed in #10342

^{Originally posted by ldthorne September 27, 2023}

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Example Code

import pytest
from fastapi import FastAPI
from starlette.testclient import TestClient


@pytest.fixture(name="client")
def get_client():
    app = FastAPI(separate_input_output_schemas=False)

    from pydantic import BaseModel, computed_field

    class Rectangle(BaseModel):
        width: int
        length: int

        @computed_field
        @property
        def area(self) -> int:
            return self.width * self.length

    @app.get("/")
    def read_root() -> Rectangle:
        return Rectangle(width=3, length=4)

    client = TestClient(app)
    return client


def test_get(client: TestClient):
    response = client.get("/openapi.json")
    data = response.json()

    rectangle_model = data["components"]["schemas"]["Rectangle"]["properties"]

    assert "area" in rectangle_model.keys()

Description

I expect that even with separate_input_output_schemas set to False the OpenAPI schema includes computed fields declared on a Pydantic model

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.103.1

Pydantic Version

2.4.1

Python Version

3.8.16

Additional Context

I think it may come from here

[tiangolo]

Fixed by #13207

Available in FastAPI 0.123.4, released in the next few hours.