树莓派Python gspread OAuth2认证失效：运行一段时间后报401错误

The 401 "UNAUTHENTICATED" error you’re hitting after your script runs for a while comes down to expired OAuth 2.0 access tokens. Service account tokens typically expire after ~1 hour, and your current setup only authenticates once at startup—there’s no logic to refresh the token when it expires. Here are two solid solutions to fix this:

Solution 1: Refresh Credentials in the Loop (Using oauth2client) #

If you want to stick with your existing oauth2client setup, modify the loop to check for expired tokens and refresh them before each request:

import gspread
from oauth2client.service_account import ServiceAccountCredentials
from oauth2client.client import Request

scope = ['https://spreadsheets.google.com/feeds', 'https://www.googleapis.com/auth/drive']
credentials = ServiceAccountCredentials.from_json_keyfile_name('auth.json', scope)
gc = gspread.authorize(credentials)
wks = gc.open('sheet').sheet1

while True:
    # Refresh credentials if the token is expired
    if credentials.access_token_expired:
        credentials.refresh(Request())
        gc = gspread.authorize(credentials)
        wks = gc.open('sheet').sheet1  # Re-fetch the worksheet after re-authentication
    
    # Your existing code (data collection, processing, etc.)
    # Add your 2-minute delay here (e.g., time.sleep(120))
    
    wks.append_row(["test", "test2"])

This checks if the token is expired before each append operation and refreshes it if needed, keeping your requests authenticated over time.

Solution 2: Migrate to google-auth (Recommended) #

The oauth2client library is deprecated, so switching to the official google-auth library is a more robust long-term fix. It automatically handles token refresh for you in the background:

First, install the required packages:

pip install gspread google-auth google-auth-oauthlib google-auth-httplib2

Then rewrite your script with google-auth:

import gspread
from google.oauth2.service_account import Credentials
from google.auth.transport.requests import Request

scope = ['https://spreadsheets.google.com/feeds', 'https://www.googleapis.com/auth/drive']
credentials = Credentials.from_service_account_file('auth.json', scopes=scope)

# Initial refresh if credentials are already expired
if not credentials.valid:
    credentials.refresh(Request())

gc = gspread.authorize(credentials)
wks = gc.open('sheet').sheet1

while True:
    # Your existing code (data collection, processing, etc.)
    # Add your 2-minute delay here
    
    # google-auth will automatically refresh the token if needed before the request
    wks.append_row(["test", "test2"])

This approach removes the need for manual token expiration checks entirely, as the library manages the token lifecycle behind the scenes.

Quick Checks to Rule Out Other Issues #

• Double-check that your service account email (from auth.json) has edit access to the target Google Sheet (you mentioned it works initially, but permissions might have changed accidentally).
• Ensure your auth.json file hasn’t been modified, corrupted, or moved from its original location.

内容的提问来源于stack exchange，提问作者otto