Unix服务器上Python调用Google Calendar API授权失败求助

按照官方教程配置Google Calendar API时，运行quickstart.py出现授权失败，控制台报错如下：

Please visit this URL to authorize this application: https://accounts.google.com/o/oauth2/auth?response_type=code&client_id=99236485634896-kkavoaib8mp8ert4eri2d5v6gicfln14i0k.apps.googleusercontent.com&redirect_uri=http%3A%2F%2Flocalhost%3A42403%2F&scope=https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fcalendar&state=XEqxqNSDNKfksdfgwUXw24JjK4EzA4G&access_type=offline
Traceback (most recent call last):
File "/home/calendar/quickstart.py", line 63, in
main()
File "/home/calendar/quickstart.py", line 33, in main
creds = flow.run_local_server(port=0)
File "/home/calendar/.local/lib/python3.10/site-packages/google_auth_oauthlib/flow.py", line 446, in run_local_server
authorization_response = wsgi_app.last_request_uri.replace("http", "https")
AttributeError: 'NoneType' object has no attribute 'replace'

点击授权链接完成账号选择和权限允许后，被重定向到http://localhost:42403/?state=XEkxqN2KMDSgXknqUXw24JjK4EzA4G&code=4/2AbUR2VOHwy3nuCXdumqaJejyAb8F0N7LXQ2JA48EGgtuzCm64uNc YJRb7wfTLgnVSA1C8g&scope=https://www.googleapis.com/auth/calendar，浏览器提示无法访问此网站。

附上quickstart.py代码：

from __future__ import print_function

import datetime
import os.path

from google.auth.transport.requests import Request
from google.oauth2.credentials import Credentials
from google_auth_oauthlib.flow import InstalledAppFlow
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError

# If modifying these scopes, delete the file token.json.
SCOPES = ['https://www.googleapis.com/auth/calendar']


def main():
    """Shows basic usage of the Google Calendar API.
    Prints the start and name of the next 10 events on the user's calendar.
    """
    creds = None
    # The file token.json stores the user's access and refresh tokens, and is
    # created automatically when the authorization flow completes for the first
    # time.
    if os.path.exists('token.json'):
        creds = Credentials.from_authorized_user_file('token.json', SCOPES)
    # If there are no (valid) credentials available, let the user log in.
    if not creds or not creds.valid:
        if creds and creds.expired and creds.refresh_token:
            creds.refresh(Request())
        else:
            flow = InstalledAppFlow.from_client_secrets_file(
                'client_secret_99236485634896-mlsfkvkldfmldfer34o3fiodfficfln14i0k.apps.googleusercontent.com.json', SCOPES)
            creds = flow.run_local_server(port=0)
        # Save the credentials for the next run
        with open('token.json', 'w') as token:
            token.write(creds.to_json())

    try:
        service = build('calendar', 'v3', credentials=creds)

        # Call the Calendar API
        now = datetime.datetime.utcnow().isoformat() + 'Z'  # 'Z' indicates UTC time
        print('Getting the upcoming 10 events')
        events_result = service.events().list(calendarId='primary', timeMin=now,
                                              maxResults=10, singleEvents=True,
                                              orderBy='startTime').execute()
        events = events_result.get('items', [])

        if not events:
            print('No upcoming events found.')
            return

        # Prints the start and name of the next 10 events
        for event in events:
            start = event['start'].get('dateTime', event['start'].get('date'))
            print(start, event['summary'])

    except HttpError as error:
        print('An error occurred: %s' % error)


if __name__ == '__main__':
    main()

问题原因与修复方案 #

核心问题 #

Unix服务器为无GUI远程环境，run_local_server()方法依赖本地浏览器和本地端口接收授权回调，但远程服务器的localhost端口无法被本地浏览器访问，导致授权回调失败，进而触发AttributeError。

修复步骤 #

• 替换授权方式：将代码中creds = flow.run_local_server(port=0)替换为creds = flow.run_console()，该方法专为无GUI环境设计，无需本地浏览器回调。
• 重新运行脚本：执行quickstart.py后，控制台会输出授权URL，复制该URL到本地浏览器打开，完成授权后获取授权码。
• 输入授权码：将浏览器中得到的授权码粘贴回服务器控制台，脚本会自动生成token.json文件。

额外注意事项 #

• 确认Google Cloud项目中，OAuth 2.0客户端ID的类型为桌面应用，而非Web应用，避免授权限制。
• 若之前生成过token.json，需先删除该文件再重新运行脚本，防止旧凭证缓存干扰。

内容的提问来源于stack exchange，提问作者Konstantin Boev