Situation description:

@app.route('/auth/audio/save', methods=['POST'])
def save_audio():
    # files = request.files
    resp_dict = {'message': "success"}
    file = request.files.get("file")
    if file.filename == "":
        resp_dict['message'] = "[No file] file.filename == ''"
        return jsonify(resp_dict), 400
    # data = request.get_json()
    data = request.form
    logger.info(f"data: {data}")
    check_required_params(data, ['user_id'])
    user_id = data["user_id"]
    audio_dir = os.path.join(app_dir, 'db_files/audio')
    save_path = os.path.join(audio_dir, f'{user_id}.bin')
    file.save(save_path)
    return jsonify(resp_dict), 200

I have a Flask view function which handles POST request that sends a file and data wrapped inside the request body.

The send request codes show below:

def test_send_audio():
    cur_dir = os.path.dirname(os.path.abspath(__file__))
    audiopath = os.path.join(cur_dir, "test.wav")
    files = {'file': open(audiopath, 'rb')}
    data = {"user_id": 2}
    # headers = {
    #     "Content-Type": "multipart/form-data",
    # }
    # NOTE: Not sure why handlers can't get files when I add headers
    response = requests.post(
        save_audio_url,
        # headers=headers,
        files=files,
        data=data,
    )

My question:

1. In view function, what is the difference between using ‘request.form’ and ‘request.get_json()’? In my case which one is the best practice? What is the best use case for the other one?
2. Why adding the headers like “Content-Type”: “multipart/form-data” will let the view funtion failed to get file when handling the request, but if I don’t add this headers it will work?
3. In general, what is the best practice to implement the case that I described?