Python MySQL 无法连接，原因不明

Question

当我尝试使用 python 连接到我的 MySQL 数据库时，由于未知原因显示错误：

dTraceback (most recent call last):
  File "/usr/local/bin/flask", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/usr/local/lib/python3.12/site-packages/flask/cli.py", line 1105, in main
    cli.main()
  File "/usr/local/lib/python3.12/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/click/decorators.py", line 92, in new_func
    return ctx.invoke(f, obj, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/flask/cli.py", line 953, in run_command
    raise e from None
  File "/usr/local/lib/python3.12/site-packages/flask/cli.py", line 937, in run_command
    app: WSGIApplication = info.load_app()
                           ^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/flask/cli.py", line 335, in load_app
    app = locate_app(import_name, name)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/flask/cli.py", line 245, in locate_app
    __import__(module_name)
  File "/app/main.py", line 2, in <module>
    import sql_code
  File "/app/sql_code.py", line 4, in <module>
    mydb = mysql.connector.connect(
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/mysql/connector/pooling.py", line 322, in connect
    return CMySQLConnection(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/mysql/connector/connection_cext.py", line 151, in __init__
    self.connect(**kwargs)
  File "/usr/local/lib/python3.12/site-packages/mysql/connector/abstracts.py", line 1399, in connect
    self._open_connection()
  File "/usr/local/lib/python3.12/site-packages/mysql/connector/connection_cext.py", line 339, in _open_connection
    raise get_mysql_exception(
mysql.connector.errors.DatabaseError: 2003 (HY000): Can't connect to MySQL server on 'localhost:3306' (99)

这些是 python 连接器的文件（针对敏感信息的审查进行了修改）

mydb = mysql.connector.connect(
    host="localhost",
    user="USERNAME_DATABASE",
    password="root_pass",
    database="mydatabase"
)

以及修改后的MYSQL文件（docker）：

FROM mysql:latest

WORKDIR /app

ADD . /app

COPY ./ex_db.sql /docker-entyypoint-initdb.d/

ENV MYSQL_HOST=localhost

ENV MYSQL_USER=USERNAME_DATABASE

ENV MYSQL_ROOT_PASSWORD=root_pass

ENV MYSQL_PASSWORD=pass

ENV MYSQL_DATABASE=mydatabase

EXPOSE 3306

两者都在最新版本的 docker 中运行

上面的代码应该可以正确连接

Answer 1

更新：修复了它，必须在 python 代码中将

host=''

设置为 mysql 服务名称，而不是 localhost 或 ip 地址。感谢那些试图帮助我的人。