Docker撰写-从另一个容器调用服务时,名称或服务未知

时间:2019-10-24 09:46:17

标签: docker docker-compose

我在一个容器中有一个Django应用,试图用Redis和Mysql容器组成它。但是,打电话

redis://redis:6379

来自Django应用,给了我

ConnectionError: Error -2 connecting redis://redis:6379. Name or service not known.

与其他可行的解决方案相比,我的设置没有任何差异。我想念什么吗? 我的docker-compose.yml

version: '3'

services:
  web:
    build: .
    environment:
      - REDIS_HOST=redis
    restart: always
    command: bash -c "python manage.py runserver --settings=settings.production_cs 0.0.0.0:8000"
    container_name: eprofi
    volumes:
      - .:/eprofi
    ports:
      - "8000:8000"
    depends_on:
      - db
      - redis
    links:
      - db:postgres
      - redis:redis
  db:
    image: mysql:latest
    command: mysqld --default-authentication-plugin=mysql_native_password
    volumes:
      - "./mysql:/var/lib/mysql"
    ports:
      - "3306:3306"
    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=secret123
      - MYSQL_DATABASE=django_app
      - MYSQL_USER=django_app
      - MYSQL_PASSWORD=django_app123
  redis:
    restart: always
    image: redis:latest
    ports:
      - "6379:6379"

我的Dockerfile

# We Use an official Python runtime as a parent image
FROM python:2.7.13
ENV DEBIAN_FRONTEND noninteractive

ENV PYTHONDONTWRITEBYTECODE 1
# The enviroment variable ensures that the python output is set straight
# to the terminal with out buffering it first
ENV PYTHONUNBUFFERED 1

# create root directory for our project in the container
RUN mkdir /www

# Set the working directory to /www
WORKDIR /www

#Upgrade pip
RUN pip install pip -U

#Install dependencies
ADD requirements.txt /www/
RUN pip install -r requirements.txt --src /usr/local/src

# Copy the current directory contents into the container at /www
ADD . /www/

然后我做

docker-compose build
docker-compose up

一切都按预期开始,但是使用“ redis:// redis:6379”调用Redis会得到上述“名称或服务未知”。错误。

我的工具

docker-compose version 1.17.1, build unknown
docker-py version: 2.5.1
Client: Docker Engine - Community
 Version:           19.03.4

更新1 我如何从python应用(旧Django)中调用Redis。

Django应用的设置:

CACHES = {
    'my_cache': {
        'BACKEND': 'redis_cache.RedisCache',
        'LOCATION': 'redis://{}:{}'.format(REDIS_HOST, REDIS_PORT),
        'KEY_PREFIX': 'project/my_cache',
        'TIMEOUT': 60*60*24,  # expire in 24 hours
        'OPTIONS': {
            'DB': 1,
            'PARSER_CLASS': 'redis.connection.HiredisParser'
        }
    },
}

致电:

cache = get_cache('my_cache')
cache.get(cache_key)

更新2

命令

ping redis

在容器中运行会给我一个错误

ping: unknown host

1 个答案:

答案 0 :(得分:1)

根据documentation,不推荐使用links选项。为了使服务互相呼叫,它们应该在同一网络上。因此,对于您的示例,解决方案是这样的。您可以了解有关网络here的更多信息。

version: '3'

services:
  web:
    ...
    networks:
      - my_network
  db:
    ...
    networks:
      - my_network
  redis:
    ...
    networks:
      - my_network

networks:
  my_network:
    external:
      name: my_network