为什么 raise_for_status() 没有捕获到错误？

Question

正在尝试在 current_track() 函数中检查 none 200 响应。可能是什么问题？它抛出 JSONDecodeError 错误。但是，如果我正确理解 raise_for_ 状态，它应该会阻止该函数尝试从错误的网页加载 JSON？如果我运行脚本没有这个检查并且没有注释行 check_playback() 它会成功捕获 JSONDecodeError.

脚本正在从 Spotify 获取数据并将其置于 vk.com 的状态。

import config
import webbrowser
import requests
import furl
import secrets
import string
import time
import os
import simplejson as json


URL_CODE_BASE_VK = 'https://oauth.vk.com/authorize'
URL_CODE_BASE_SP = 'https://accounts.spotify.com/authorize'
URL_TOKEN_VK = 'https://oauth.vk.com/access_token'
URL_TOKEN_SP = 'https://accounts.spotify.com/api/token'
URL_TRACK = 'https://api.spotify.com/v1/me/player/currently-playing'
URL_STATUS = 'https://api.vk.com/method/status.set'
EXP_IN_TOKEN_SP = 3400
EXP_IN_TOKEN_VK = 86400
FILE_TOKEN_VK = 'vk_token.json'
FILE_TOKEN_SP = 'sp_token.json'


def get_auth_code_vk():
    url_code_params = {
                        'client_id': config.CLIENT_ID_VK,
                        'response_type': 'code',
                        'redirect_uri': 'https://oauth.vk.com/blank.html',
                        'v': 5.92,
                        'scope': 'status',
                        'state': gen_state(),
                        'display': 'page'
    }

    code = url_open(URL_CODE_BASE_VK, url_code_params)
    return parse_code(code)


def get_auth_code_sp():
    url_code_params = {
                        'client_id': config.CLIENT_ID_SP,
                        'response_type': 'code',
                        'redirect_uri': 'https://www.spotify.com/',
                        'scope': 'user-read-currently-playing',
                        'state': gen_state()
    }

    code = url_open(URL_CODE_BASE_SP, url_code_params)
    return parse_code(code)


def gen_state():
    symbols = string.ascii_lowercase + string.digits
    return ''.join(secrets.choice(symbols) for _ in range(12))


def url_open(url_base, url_params):
    url_code_full = furl.furl(url_base).add(url_params).url
    webbrowser.open_new_tab(url_code_full)
    input_url = input('Enter the whole URL, that you have been redirected on: ')

    return input_url


def parse_code(url):
    return (url.split("code=")[1]).split("&state=")[0]


def get_token_vk():
    data = {
            'grant_type': 'authorization_code',
            'code': get_auth_code_vk(),
            'redirect_uri': 'https://oauth.vk.com/blank.html',
            'client_id': 6782333,
            'client_secret': config.CLIENT_SECRET_VK
    }

    response = requests.post(url=URL_TOKEN_VK, data=data).json()
    write_file(FILE_TOKEN_VK, response)


def get_token_sp():
    data = {
            'grant_type': 'authorization_code',
            'code': get_auth_code_sp(),
            'redirect_uri': 'https://www.spotify.com/',
            'client_id': config.CLIENT_ID_SP,
            'client_secret': config.CLIENT_SECRET_SP
    }

    response = requests.post(url=URL_TOKEN_SP, data=data).json()
    write_file(FILE_TOKEN_SP, response)


def write_file(tkn_file, response):
    dict = {}
    dict['token'] = response["access_token"]
    dict['time'] = time.time()

    with open(tkn_file, 'w') as file:
        file.write(json.dumps(dict))


def load_file(tkn_file):
    with open(tkn_file) as file:
        data = json.load(file)
    return data


def set_status():
    params = {
              'v': 5.92,
              'access_token': load_file(FILE_TOKEN_VK)['token'],
              'text': current_track()
    }

    set_status = requests.get(url=URL_STATUS, params=params)


def track_data():
    tkn_file =  load_file(FILE_TOKEN_SP)['token']
    headers = {
               'Accept': 'application/json',
               'Authorization': f'Bearer {tkn_file}'
    }

    return requests.get(url=URL_TRACK, headers=headers)


def current_track():
    response = track_data()
    print(response)

    try:
        response.raise_for_status()
    except requests.exceptions.HTTPError as e:
        return "Error: " + str(e)

    # data = track_data().json()
    data = response.json()
    artist = data['item']['artists'][0]['name']
    track = data['item']['name']

    return(f'{artist} - {track}')


def check_playback():
    set_status()
    print(current_track())
    # try:
    #     set_status()
    #     print(current_track())
    # except json.decoder.JSONDecodeError:
    #     print('Not playing')


def token_missing(file):
    return not os.path.isfile(file)


def token_expired(file, exp_in):
    return time.time() - load_file(file)['time'] > exp_in


def token_not_valid(file, exp_in):
    return token_missing(file) or token_expired(file, exp_in)


def run_script():
    if token_not_valid(FILE_TOKEN_VK, EXP_IN_TOKEN_VK):
        get_token_vk()

    if token_not_valid(FILE_TOKEN_SP, EXP_IN_TOKEN_SP):
        get_token_sp()

    check_playback()


if __name__ == "__main__":
    run_script()

Error screen

Answer 1

raise_for_status() 只会在 server 向您报告错误时引发异常（即便如此，仅当它实际上遵循 HTTP 规范并返回 HTTP错误代码）。

图书馆无法知道响应不正确。即使它的格式正确 JSON，它也无法知道您希望它遵循什么模式（应该出现哪些字段，以及这些字段应该具有什么类型）。即使它知道模式并验证了它，也无法知道数据实际上是正确的而不是当场编造的。

为什么 raise_for_status() 没有捕获到错误？

Why raise_for_status() did not catch the error?

python

api-design

spotify

python-3.x

python-requests