How to test against UploadFile parameter

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Example

Here’s a self-contained, minimal, reproducible, example with my use case:

from fastapi import FastAPI

router = FastAPI()


@router.post("/_config")
def create_index_config(upload_file: UploadFile = File(...)):

    config = settings.reads()
    created_config_file: Path = Path(config.config_dir, upload_file.filename)

    try:
        with created_config_file.open('wb') as write_file:
            shutil.copyfileobj(upload_file.file, write_file)

    except Exception as err:
        raise HTTPException(detail=f'{err} encountered while uploading {upload_file.filename}',
                            status_code=HTTPStatus.INTERNAL_SERVER_ERROR)
    finally:
        upload_file.file.close()

    return JSONResponse({"message": f'uploaded config {upload_file.filename}'})

Description

I’m just trying to test against an endpoint that uses uploadfile and I can’t find how to send a json file to fastapi

def test_one():
  _test_upload_file = <path to file>
 with TestClient(app) as client:
        # TODO how to upload a file
        response = client.post('/_config',
                               data= <assuming something goes here ???> )
        assert response.status_code == HTTPStatus.CREATED

Environment

• OS: [e.g. Linux / Windows / macOS]: OSX/docker
• FastAPI Version [e.g. 0.3.0]: fastapi==0.54.1
• Python version: Python 3.6.8

Additional context

data=_test_upload_file.open('rb') yields a 422 error I have also tried this and get a 422 error