from fastapi import FastAPI from fastapi.testclient import TestClient app = FastAPI() @app.get("/", openapi_extra={"x-custom-extension": "value"}) def route_with_extras(): return {} client = TestClient(app) def test_get_route(): response = client.get("/") assert response.status_code == 200, response.text assert response.json() == {} def test_openapi(): response = client.get("/openapi.json") assert response.status_code == 200, response.text assert response.json() == { "openapi": "3.1.0", "info": {"title": "FastAPI", "version": "0.1.0"}, "paths": { "/": { "get": { "responses": { "200": { "description": "Successful Response", "content": {"application/json": {"schema": {}}}, }, }, "summary": "Route With Extras", "operationId": "route_with_extras__get", "x-custom-extension": "value", } }, }, }