使用Google Forms API获取表单时遇RefreshError报错求助

我要给社区申请表单做个评分机器人，调用Google Forms API获取表单时碰到了RefreshError报错。

最小复现代码 #

# Google Credentials

from google.oauth2 import service_account

SCOPES = ['https://www.googleapis.com/auth/drive', 'https://www.googleapis.com/auth/forms.body'][0]
SERVICE_ACCOUNT_FILE = 'key.json'
credentials = service_account.Credentials.from_service_account_file(SERVICE_ACCOUNT_FILE, scopes=SCOPES)

import googleapiclient.discovery

forms = googleapiclient.discovery.build('forms', 'v1', credentials=credentials)
form_id = '__omitted__'
result = forms.forms().get(formId=form_id).execute()
print(result)

报错日志 #

Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/google/oauth2/_client.py", line 323, in jwt_grant
    access_token = response_data["access_token"]
                   ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^
KeyError: 'access_token'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "__omitted__", line 33, in <module>
    result = forms.forms().get(formId=form_id).execute()
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/googleapiclient/_helpers.py", line 130, in positional_wrapper
    return wrapped(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/googleapiclient/http.py", line 923, in execute
    resp, content = _retry_request(
                    ^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/googleapiclient/http.py", line 191, in _retry_request
    resp, content = http.request(uri, method, *args, **kwargs)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/google_auth_httplib2.py", line 209, in request
    self.credentials.before_request(self._request, method, uri, request_headers)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/google/auth/credentials.py", line 156, in before_request
    self.refresh(request)
    ^^^^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/google/oauth2/service_account.py", line 438, in refresh
    access_token, expiry, _ = _client.jwt_grant(
                              ^^^^^^^^^^^^^^^^^^
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/google/oauth2/_client.py", line 328, in jwt_grant
    six.raise_from(new_exc, caught_exc)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<string>", line 3, in raise_from
google.auth.exceptions.RefreshError: ('No access token in response.', {'id_token': '__omitted__'})

已做排查：服务账号已加入Owner组，Forms API已启用。

解决方案 #

1. 修正权限范围（Scopes） #

代码里通过[0]只取了Drive权限，但调用Forms API的forms.get接口需要Forms相关权限。修改SCOPES配置，确保包含Forms权限：

# 保留两个权限（如果需要操作Drive的话）
SCOPES = ['https://www.googleapis.com/auth/drive', 'https://www.googleapis.com/auth/forms.body']
# 或仅保留Forms权限（无需Drive操作时）
# SCOPES = ['https://www.googleapis.com/auth/forms.body']

不要用索引截断列表，否则会丢失Forms权限，导致无法生成正确的访问令牌。

2. 共享目标表单给服务账号 #

即使服务账号在Owner组，仍需将目标Google表单共享给服务账号邮箱（可在key.json的client_email字段找到），设置为编辑者或查看者权限，确保服务账号能访问该表单。

3. 验证服务账号与API状态 #

• 确认服务账号确实拥有项目Owner权限
• 重新禁用再启用Forms API，确保API状态生效

内容的提问来源于stack exchange，提问作者openwld