fastapi/tests/test_enforce_once_required_parameter.py

from typing import Optional

from fastapi import Depends, FastAPI, Query, status
from fastapi.testclient import TestClient

app = FastAPI()


def _get_client_key(client_id: str = Query(...)) -> str:
    return f"{client_id}_key"


def _get_client_tag(client_id: Optional[str] = Query(None)) -> Optional[str]:
    if client_id is None:
        return None
    return f"{client_id}_tag"


@app.get("/foo")
def foo_handler(
    client_key: str = Depends(_get_client_key),
    client_tag: Optional[str] = Depends(_get_client_tag),
):
    return {"client_id": client_key, "client_tag": client_tag}


client = TestClient(app)

expected_schema = {
    "components": {
        "schemas": {
            "HTTPValidationError": {
                "properties": {
                    "detail": {
                        "items": {"$ref": "#/components/schemas/ValidationError"},
                        "title": "Detail",
                        "type": "array",
                    }
                },
                "title": "HTTPValidationError",
                "type": "object",
            },
            "ValidationError": {
                "properties": {
                    "loc": {
                        "items": {"anyOf": [{"type": "string"}, {"type": "integer"}]},
                        "title": "Location",
                        "type": "array",
                    },
                    "msg": {"title": "Message", "type": "string"},
                    "type": {"title": "Error Type", "type": "string"},
                },
                "required": ["loc", "msg", "type"],
                "title": "ValidationError",
                "type": "object",
            },
        }
    },
    "info": {"title": "FastAPI", "version": "0.1.0"},
    "openapi": "3.1.0",
    "paths": {
        "/foo": {
            "get": {
                "operationId": "foo_handler_foo_get",
                "parameters": [
                    {
                        "in": "query",
                        "name": "client_id",
                        "required": True,
                        "schema": {"title": "Client Id", "type": "string"},
                    },
                ],
                "responses": {
                    "200": {
                        "content": {"application/json": {"schema": {}}},
                        "description": "Successful Response",
                    },
                    "422": {
                        "content": {
                            "application/json": {
                                "schema": {
                                    "$ref": "#/components/schemas/HTTPValidationError"
                                }
                            }
                        },
                        "description": "Validation Error",
                    },
                },
                "summary": "Foo Handler",
            }
        }
    },
}


def test_schema():
    response = client.get("/openapi.json")
    assert response.status_code == status.HTTP_200_OK
    actual_schema = response.json()
    assert actual_schema == expected_schema


def test_get_invalid():
    response = client.get("/foo")
    assert response.status_code == status.HTTP_422_UNPROCESSABLE_ENTITY


def test_get_valid():
    response = client.get("/foo", params={"client_id": "bar"})
    assert response.status_code == 200
    assert response.json() == {"client_id": "bar_key", "client_tag": "bar_tag"}