家庭PC搭建Python与Jupyter遇Failed to Fetch错误求助

环境信息 #

Selected Jupyter core packages...
IPython          : 8.26.0
ipykernel        : 6.29.5
ipywidgets       : not installed
jupyter_client   : 8.6.2
jupyter_core     : 5.7.2
jupyter_server   : 2.14.2
jupyterlab       : 4.2.4
nbclient         : 0.10.0
nbconvert        : 7.16.4
nbformat         : 5.10.4
notebook         : 7.2.1
qtconsole        : not installed
traitlets        : 5.14.3

一、修复Jupyter "Failed to Fetch" 错误 #

• 清理Chrome缓存与Cookie：按下Ctrl+Shift+Delete，勾选「缓存的图片和文件」「Cookie及其他网站数据」，选择「所有时间」后执行删除，重启浏览器再打开Jupyter
• 重启Jupyter服务：终端按Ctrl+C终止当前服务，重新执行jupyter notebook
• 检查端口占用：
  • Windows：运行netstat -ano | findstr :8888，找到PID后打开任务管理器结束对应进程，再重启Jupyter；或指定端口启动jupyter notebook --port 8889
  • Mac/Linux：运行lsof -i :8888，用kill -9 <PID>终止进程后重启
• 重装核心依赖：在Anaconda终端执行conda install jupyter notebook ipykernel --force-reinstall
• 禁用浏览器扩展：临时关闭Chrome所有扩展程序，再访问Jupyter页面测试

二、Python与Jupyter基础操作 #

• 环境隔离：用Anaconda创建独立环境conda create -n py312 python=3.12.4，激活环境conda activate py312
• 内核配置：激活环境后执行python -m ipykernel install --user --name py312 --display-name "Python 3.12.4 (Anaconda)"，在Notebook的「Kernel」菜单切换内核
• Notebook常用操作：
  • Shift+Enter：运行当前单元格并跳转至下一个
  • Ctrl+S：保存Notebook文件
  • %run script.py：在单元格中运行外部Python脚本
  • 用#添加注释，print()输出调试信息

三、Jupyter中配置Quarto #

• 安装Quarto：在Anaconda环境执行conda install quarto -c conda-forge
• 创建Quarto Notebook：在Jupyter界面点击File > New > Quarto Notebook，或终端执行quarto create notebook gmail_auto.ipynb
• 配置输出格式：在Notebook顶部的YAML块中定义渲染参数，示例：

---
title: "Gmail清理自动化练习"
format:
  html:
    toc: true
    code-fold: true
    theme: cosmo
---

• 渲染文档：终端执行quarto render gmail_auto.ipynb --to html，或在Jupyter界面点击「Render」按钮生成HTML报告

四、Gmail清理自动化开发 #

• 安装依赖：在环境中执行pip install google-api-python-client google-auth-httplib2 google-auth-oauthlib
• API配置：在Google Cloud控制台创建项目，启用Gmail API，下载credentials.json文件到Notebook工作目录
• 核心代码示例：

from googleapiclient.discovery import build
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request
import pickle
import os.path

# 权限范围，modify允许修改邮件
SCOPES = ['https://www.googleapis.com/auth/gmail.modify']

def get_gmail_service():
    creds = None
    # 读取已保存的令牌
    if os.path.exists('token.pickle'):
        with open('token.pickle', 'rb') as token:
            creds = pickle.load(token)
    # 无有效令牌则重新授权
    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('credentials.json', SCOPES)
            creds = flow.run_local_server(port=0)
        # 保存令牌
        with open('token.pickle', 'wb') as token:
            pickle.dump(creds, token)
    return build('gmail', 'v1', credentials=creds)

def delete_spam_emails(service):
    # 获取垃圾邮件列表
    results = service.users().messages().list(userId='me', labelIds=['SPAM']).execute()
    messages = results.get('messages', [])
    if not messages:
        print("无垃圾邮件")
        return
    # 批量删除垃圾邮件
    for msg in messages:
        service.users().messages().delete(userId='me', id=msg['id']).execute()
    print(f"已删除{len(messages)}封垃圾邮件")

if __name__ == '__main__':
    service = get_gmail_service()
    delete_spam_emails(service)

• Jupyter调试技巧：将代码拆分到多个单元格，逐块运行并检查输出；用service.users().labels().list(userId='me').execute()查看所有邮件标签，确认目标标签ID

内容的提问来源于stack exchange，提问作者RAMO46