PyScript网页连接MySQL：包安装失败与连接异常问题求助

问题描述 #

1. 包安装失败报错 #

初始使用mysql.connector时触发PY1001错误：无法找到纯Python 3 Wheel包，尝试7年前的pip install --allow-external mysql-connector-python mysql-connector-python命令，因依赖旧版pip（8.x）无法生效。本地已安装pymysql和mysql-connector-python，相关环境信息如下：

[root@localhost ~]# pip show pymysql
Name: PyMySQL
Version: 1.0.2
Summary: Pure Python MySQL Driver
Home-page: https://github.com/PyMySQL/PyMySQL/
Author: yutaka.matsubara
Author-email: yutaka.matsubara@gmail.com
License: "MIT"
Location: /usr/local/lib/python3.6/site-packages
Requires:
Required-by:
[root@localhost ~]# pip show mysql-connector-python
Name: mysql-connector-python
Version: 8.0.31
Summary: MySQL driver written in Python
Home-page: http://dev.mysql.com/doc/connector-python/en/index.html
Author: Oracle and/or its affiliates
Author-email:
License: GNU GPLv2 (with FOSS License Exception)
Location: /usr/local/lib/python3.6/site-packages
Requires: protobuf
Required-by:
[root@localhost ~]# pip list
Package                Version
---------------------- -------
mysql-connector        2.2.9
mysql-connector-python 8.0.31
pip                    21.3.1
protobuf               3.19.6
PyMySQL                1.0.2
setuptools             59.6.0

2. 连接数据库报错 #

解决包安装问题后，出现连接错误，报错日志：

Traceback (most recent call last):
  File "/lib/python3.10/site-packages/mysql/connector/network.py", line 567, in open_connection
    self.sock.connect(sockaddr)
BlockingIOError: [Errno 26] Operation in progress

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

Traceback (most recent call last):
  File "/lib/python3.10/site-packages/_pyodide/_base.py", line 435, in eval_code
    .run(globals, locals)
  File "/lib/python3.10/site-packages/_pyodide/_base.py", line 304, in run
    coroutine = eval(self.code, globals, locals)
  File "<exec>", line 3, in <module>
  File "/lib/python3.10/site-packages/mysql/connector/pooling.py", line 287, in connect
    return MySQLConnection(*args, **kwargs)
  File "/lib/python3.10/site-packages/mysql/connector/connection.py", line 137, in __init__
    self.connect(**kwargs)
  File "/lib/python3.10/site-packages/mysql/connector/abstracts.py", line 1108, in connect
    self._open_connection()
  File "/lib/python3.10/site-packages/mysql/connector/connection.py", line 533, in _open_connection
    self._socket.open_connection()
  File "/lib/python3.10/site-packages/mysql/connector/network.py", line 569, in open_connection
    raise InterfaceError(
mysql.connector.errors.InterfaceError: 2003: Can't connect to MySQL server on '196.168.100.141:3306' (26 Operation in progress)

本地普通Python脚本使用相同连接参数可正常连接，但PyScript中无法连接，原PyScript代码：

<py-script>
    import mysql.connector

    mydb = mysql.connector.connect(
      host="196.168.100.141",
      user="root",
      password="password123", 
      database="database_db",  
      auth_plugin='mysql_native_password'
    )
                    
    mycursor = mydb.cursor()
    mycursor.execute("SELECT row_01 FROM database")                       
                                         
    myresult = mycursor.fetchall()
    
    list_01 = []
    
    for row in myresult:
      temp_val = row[0]
      list_01.append(temp_val)
</py-script>

解决方案 #

针对包安装失败的问题 #

PyScript基于Pyodide运行，仅支持纯Python包或提供Pyodide兼容Wheel的包。mysql.connector官方包包含C扩展，无法直接在Pyodide中运行；而PyMySQL是纯Python实现的MySQL驱动，完全兼容Pyodide，直接改用PyMySQL即可。

在HTML中添加包配置：

<py-config>
    packages = ["pymysql"]
</py-config>

针对连接报错的问题 #

PyScript运行在浏览器环境中，存在两个核心限制导致直接连接MySQL失败：

• 浏览器同源策略限制：无法直接访问局域网内的MySQL服务（MySQL本身不支持CORS配置）
• Pyodide网络限制：不支持阻塞式Socket连接，而MySQL驱动的默认连接均为阻塞式，触发BlockingIOError

推荐方案：后端代理中转数据

不要在前端PyScript中直接连接MySQL，搭建后端接口负责数据库交互，前端通过HTTP请求获取数据。

步骤1：编写后端接口（以Flask为例）

from flask import Flask, jsonify
from flask_cors import CORS
import pymysql

app = Flask(__name__)
CORS(app)  # 解决跨域问题

@app.route('/get-data')
def get_data():
    conn = pymysql.connect(
        host='196.168.100.141',
        user='root',
        password='password123',
        database='database_db',
        cursorclass=pymysql.cursors.DictCursor
    )
    try:
        with conn.cursor() as cursor:
            cursor.execute("SELECT row_01 FROM database")
            results = cursor.fetchall()
            return jsonify([row['row_01'] for row in results])
    finally:
        conn.close()

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000, debug=True)

注：需先安装依赖pip install flask flask-cors pymysql

步骤2：修改PyScript代码请求后端接口

<py-config>
    packages = ["requests"]
</py-config>

<py-script>
    import requests

    try:
        response = requests.get("http://你的后端IP:5000/get-data")
        response.raise_for_status()
        list_01 = response.json()
        # 此处可添加数据展示逻辑，比如渲染到页面
        print(list_01)
    except Exception as e:
        print(f"请求失败: {e}")
</py-script>

备选测试方案（不推荐生产）

若需临时测试，可尝试使用PyMySQL配合异步操作，但仅能连接公网支持HTTP隧道的MySQL服务，且可行性极低，不用于生产环境。

内容的提问来源于stack exchange，提问作者user20861658