django无法在docker-compose中连接mysql

Question

我是docker的新手,现在我试图通过docker-compose在docker中使用mariadb运行django,但我总是遇到这个错误:

我用Docker version 17.09.1-ce, build 19e2cf6,docker-compose version 1.18.0, build 8dd22a9

django.db.utils.OperationalError:(2003年,'无法连接到'mariadb55上的MySQL服务器'(111"连接被拒绝")')

我可以docker-compose up db在本地或远程运行后正确连接数据库,我甚至可以python manage.py runserver 0.0.0.0:6001在anaconda虚拟环境中正确运行db,通过设置settings.py文件的参数来连接docker中的服务,如下所示:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'test',
        'USER': 'belter',
        # 'HOST': 'mariadb55',
        'HOST': '127.0.0.1',
        'PORT': '3302',
        'PASSWORD': 'belter_2017',
        'default-character-set': 'utf8',
        'OPTIONS': {
            'sql_mode': 'traditional',
        }
    }
}

这是我的docker-compose.yml文件

version: '3'

services:
  db:
    image: mariadb:5.5
    restart: always
    environment:
      - MYSQL_HOST=localhost
      - MYSQL_PORT=3306
      - MYSQL_ROOT_HOST=%
      - MYSQL_DATABASE=test
      - MYSQL_USER=belter
      - MYSQL_PASSWORD=belter_2017
      - MYSQL_ROOT_PASSWORD=123456_abc
    volumes:
      - /home/belter/mdbdata/mdb55:/var/lib/mysql
    ports:
      - "3302:3306"
  web:
    image: onlybelter/django_py35
    command: python3 manage.py runserver 0.0.0.0:6001
    volumes:
      - /mnt/data/www/mysite:/djcode
    ports:
      - "6001:6001"
    depends_on:
      - db
    links:
      - db:mariadb55

我几乎尝试了所有我能找到的东西,但仍然无法弄明白,任何帮助都会很好!

我尝试过的:

Docker组合mysql连接失败

使用docker-compose链接django和mysql容器

Django通过docker-compose连接到postgres

Answer 1

最后,我想通了!关键的一点是,正如@SangminKi​​m说,我需要使用3306未3302中settings.py,并使用db如HOST没有127.0.0.1.

所以现在这是我的docker-compose.yml文件:

version: '3'

services:
  db:
    image: mariadb:5.5
    restart: always
    environment:
      - MYSQL_HOST=localhost
      - MYSQL_PORT=3306  # cannot change this port to other number
      - MYSQL_ROOT_HOST=%
      - MYSQL_DATABASE=test
      - MYSQL_USER=belter
      - MYSQL_PASSWORD=belter_2017
      - MYSQL_ROOT_PASSWORD=123456_abc
    volumes:
      - /home/belter/mdbdata/mdb55:/var/lib/mysql
    ports:
      - "3302:3306"
  web:
    image: onlybelter/django_py35
    command: python3 manage.py runserver 0.0.0.0:6001
    volumes:
      - .:/djcode
    ports:
      - "6001:6001"
    depends_on:
      - db

所以,现在我们可以连接此泊坞窗MySQL的通过mysql -h 127.0.0.1 -P 3302 -u root -p直接的外壳,但我们不得不使用db和3306在Django settings.py文件:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'test',
        'USER': 'belter',
        # 'HOST': 'mariadb55',
        'HOST': 'db',  #<---
        'PORT': '3306',   #<---
        'PASSWORD': 'belter_2017',
        'default-character-set': 'utf8',
        'OPTIONS': {
            'sql_mode': 'traditional',
        }
    }
}

我们仍然可以通过在docker-compose.yml文件中运行额外命令来检查此端口是否已打开:

...
  web:
    image: onlybelter/django_py35
    command: /bin/sh -c "python check_db.py --service-name mysql --ip db --port 3306"
    volumes:
      - .:/djcode
...

这是check_db.py文件:

# check_db.py 

import socket
import time
import argparse
""" Check if port is open, avoid docker-compose race condition """

parser = argparse.ArgumentParser(description='Check if port is open, avoid\
                                 docker-compose race condition')
parser.add_argument('--service-name', required=True)
parser.add_argument('--ip', required=True)
parser.add_argument('--port', required=True)

args = parser.parse_args()

# Get arguments
service_name = str(args.service_name)
port = int(args.port)
ip = str(args.ip)

# Infinite loop
while True:
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    result = sock.connect_ex((ip, port))
    if result == 0:
        print("{0} port is open! Bye!".format(service_name))
        break
    else:
        print("{0} port is not open! I'll check it soon!".format(service_name))
        time.sleep(3)

顺便说一句,这是我的构建Dockerfiledjango-py35:

FROM python:3.5-alpine
MAINTAINER Xin Xiong "xiongxin20008@126.com"
ENV PYTHONUNBUFFERED 1
RUN set -e; \
        apk add --no-cache --virtual .build-deps \
                gcc \
                libc-dev \
                linux-headers \
                mariadb-dev \
                python3-dev \
                postgresql-dev \
                freetype-dev \
                libpng-dev \
                g++ \
        ;
RUN mkdir /djcode
WORKDIR /djcode
ENV REFRESHED_AT 2017-12-25
ADD requirements.txt /djcode/
RUN pip install --no-cache-dir -r /djcode/requirements.txt
RUN pip install uwsgi
ADD . /djcode/  # copy . to /djcode/
EXPOSE 6001

从这里查看更多详细信息:https://github.com/OnlyBelter/django-compose