Mariadb docker 容器无法使用 Python 连接到主机上的 MySQL 服务器（111 连接被拒绝）

Question

我正在尝试使用 docker-compose:

与 python 连接 mariadb

docker-compose.yml

    version: '2'
    services:
      mariadb:
        image: bitnami/mariadb
        ports:
          - "3306:3306"
        environment:
          MARIADB_DATABASE: 'mary_db'
          MARIADB_USER: user2
          MARIADB_PASSWORD: 'pass1234'
      consumer:
          build: ./consumer
          links:
            - mariadb

consumer.py

    import mysql.connector as mariadb1

    mariadb_connection = mariadb1.connect(host='mariadb',
                                  port=3306,
                                 user='user2',
                                 password='pass1234',
                                 database='mary_db')

    cursor = mariadb_connection.cursor(buffered=True)

    try:
        cursor.execute('DROP TABLE names')
    except:
        pass

    comm = "CREATE TABLE names(id VARCHAR(20), location VARCHAR(100)," \
   "PRIMARY KEY (mac,location)) ENGINE=InnoDB"

    cursor.execute(comm)
    print 'created'

Dockerfile 入口点只是调用 consumer.py 函数，如：

    ENTRYPOINT python -u consumer.py

问题非常随机（超过 %90 次试验），python 代码无法连接数据库并打印此错误：

File "consumer.py", line 7, in database='mary_db') File "/usr/local/lib/python2.7/dist-packages/mysql/connector/init.py", line 179, in connect return MySQLConnection(*args, **kwargs) File "/usr/local/lib/python2.7/dist-packages/mysql/connector/connection.py", line 95, in init self.connect(**kwargs) File "/usr/local/lib/python2.7/dist-packages/mysql/connector/abstracts.py", line 719, in connect self._open_connection() File "/usr/local/lib/python2.7/dist-packages/mysql/connector/connection.py", line 206, in _open_connection self._socket.open_connection() File "/usr/local/lib/python2.7/dist-packages/mysql/connector/network.py", line 475, in open_connection errno=2003, values=(self.get_address(), _strioerror(err))) mysql.connector.errors.InterfaceError: 2003: Can't connect to MySQL server on 'mariadb:3306' (111 Connection refused)

知道发生了什么吗？

Answer 1

问题不在于数据库或Python代码；这是一个来自 Docker 的问题，因为数据库需要一些时间来加载并且 python (consumer.py) 容器启动速度比数据库快。

可能的解决方案：

docker 健康检查

等待时间 docker

向 python 消费者添加延迟

Answer 2

此问题是由于 python 容器在正确执行数据库容器之前执行的。要解决此问题，请在 mysql 连接之前使用以下代码行。

import time
time.sleep(1)

您的代码应如下所示：

import time
time.sleep(1)

mydb = mysql.connector.connect(
  host="<host>",
  user="<user_name>",
  passwd="<pswd>",
  database = "<DB_name>",
  buffered=True
)

cursor = mydb.cursor()

它对我有效。希望它也对你有用。

Mariadb docker 容器无法使用 Python 连接到主机上的 MySQL 服务器（111 连接被拒绝）

Mariadb docker container Can't connect to MySQL server on host (111 Connection refused) with Python

python

mysql

mariadb

docker