docker-compose使用 docker-compose详解

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mob6454cc667b1d 2023-09-21 11:47:35

文章标签 docker-compose使用 docker linux 运维 redis 文章分类 Docker 云计算

Docker Compose是什么

安装docker-compose

使用docker-compose

常用命令

Compose and WordPress

Docker Compose是什么

Docker Compose是一款容器编排工具，Compose是在一台机器上管理多个容器。

Compose 是 Docker 容器进行编排的工具，定义和运行多容器的应用，可以一条命令启动多个容器，使用Docker Compose不再需要使用shell脚本来启动容器。

Compose 通过一个配置文件来管理多个Docker容器，在配置文件中，所有的容器通过services来定义，然后使用docker-compose脚本来启动、停止和重启应用，和应用中的服务以及所有依赖服务的容器，非常适合组合使用多个容器进行开发的场景。

官网地址：Overview of Docker Compose | Docker Documentation

安装docker-compose

1、从daocloud上下载docker-compose二进制文件安装

[root@docker ~]# curl -L https://get.daocloud.io/docker/compose/releases/download/1.29.2/docker-compose-`uname -s`-`uname -m` -o /usr/local/bin/docker-compose

2、添加可执行权限

[root@docker ~]# chmod +x /usr/local/bin/docker-compose

3、测试安装结果

[root@docker ~]# docker-compose --version (-v也可以查看版本)
docker-compose version 1.29.2, build 5becea4c

使用docker-compose

1、为docker-compose项目创建一个目录

mkdir compose-test
cd compose-test

2、在该目录下创建一个名为 app.py 的文件，并粘贴以下内容

vim app.py(粘贴之前得在命令模式下输入":set paste",然后按i进入输入模式粘贴)

import time

import redis
from flask import Flask

app = Flask(__name__)
cache = redis.Redis(host='redis', port=6379)

def get_hit_count():
    retries = 5
    while True:
        try:
            return cache.incr('hits')
        except redis.exceptions.ConnectionError as exc:
            if retries == 0:
                raise exc
            retries -= 1
            time.sleep(0.5)

@app.route('/')
def hello():
    count = get_hit_count()
    return 'Hello World! I have been seen {} times.\n'.format(count)

3、在该目录下创建一个名为 requirements.txt 的文件，并粘贴以下内容

flask
redis

4、创建一个Dockerfile，并粘贴以下内容

vim Dockerfile

# syntax=docker/dockerfile:1
FROM python:3.7-alpine
WORKDIR /code
ENV FLASK_APP=app.py
ENV FLASK_RUN_HOST=0.0.0.0
RUN apk add --no-cache gcc musl-dev linux-headers
COPY requirements.txt requirements.txt
RUN pip install -r requirements.txt
EXPOSE 5000
COPY . .
CMD ["flask", "run"]

5、在该目录下创建一个名为 docker-compose.yml 的文件，并粘贴以下内容

vim docker-compose.yml

version: "3.9"
services:
  web:
    build: .
    ports:
      - "5000:5000"
  redis:
    image: "redis:alpine"
    ports:
      - "6379:6379"

这个Compose文件定义了web和redis这两个服务。

6、使用Compose构建并运行程序

[root@manager compose-test]# docker-compose up
WARNING: The Docker Engine you're using is running in swarm mode.

Compose does not use swarm mode to deploy services to multiple nodes in a swarm. All containers will be scheduled on the current node.

To deploy your application across the swarm, use `docker stack deploy`.

Creating network "compose-test_default" with the default driver
Creating compose-test_web_1   ... done
Creating compose-test_redis_1 ... done
Attaching to compose-test_web_1, compose-test_redis_1
redis_1  | 1:C 05 Sep 2021 08:28:48.263 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
redis_1  | 1:C 05 Sep 2021 08:28:48.263 # Redis version=6.2.5, bits=64, commit=00000000, modified=0, pid=1, just started
redis_1  | 1:C 05 Sep 2021 08:28:48.263 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
redis_1  | 1:M 05 Sep 2021 08:28:48.264 * monotonic clock: POSIX clock_gettime
redis_1  | 1:M 05 Sep 2021 08:28:48.265 * Running mode=standalone, port=6379.
redis_1  | 1:M 05 Sep 2021 08:28:48.265 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.
redis_1  | 1:M 05 Sep 2021 08:28:48.265 # Server initialized
redis_1  | 1:M 05 Sep 2021 08:28:48.265 # WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.
redis_1  | 1:M 05 Sep 2021 08:28:48.268 * Ready to accept connections
web_1    |  * Serving Flask app 'app.py' (lazy loading)
web_1    |  * Environment: development
web_1    |  * Debug mode: on
web_1    |  * Running on all addresses.
web_1    |    WARNING: This is a development server. Do not use it in a production deployment.
web_1    |  * Running on http://172.19.0.2:5000/ (Press CTRL+C to quit)
web_1    |  * Restarting with stat
web_1    |  * Debugger is active!
web_1    |  * Debugger PIN: 910-519-966

[root@manager compose-test]# docker-compose up -d    Compose启动的容器以后台方式运行

Starting compose-test_redis_1 ... done
Starting compose-test_web_1   ... done

web端口访问测试

常用命令

docker-compose up      # 创建并启动容器
docker-compose ps      # 显示所有容器
docker-compose down    # 停止和删除容器、网络、卷、镜像，这些内容是通过docker-compose up命令创建的.  默认值删除容器、网络，可以通过指定rmi、volumes参数删除镜像和卷
docker-compose stop    # 停止所有服务（容器）
docker-compose top     # 显示正在运行的进程

Compose and WordPress

了解如何使用Compose来设置和运行WordPress

WordPress：可以快速搭建一个自己的网站的框架

快速入门指南：Quickstart: Compose and WordPress | Docker Documentation

1、新建一个目录
# cd my_wordpress

2、在该目录下创建一个名为docker-compose.yml的文件
# vim docker-compose.yml
version: "3.9"
    
services:
  db:
    image: mysql:5.7
    volumes:
      - db_data:/var/lib/mysql
    restart: always
    environment:
      MYSQL_ROOT_PASSWORD: 123456
      MYSQL_DATABASE: wordpress
      MYSQL_USER: wordpress
      MYSQL_PASSWORD: wordpress
    
  wordpress:
    depends_on:
      - db
    image: wordpress:latest
    volumes:
      - wordpress_data:/var/www/html
    ports:
      - "8000:80"
    restart: always
    environment:
      WORDPRESS_DB_HOST: db:3306
      WORDPRESS_DB_USER: wordpress
      WORDPRESS_DB_PASSWORD: wordpress
      WORDPRESS_DB_NAME: wordpress
volumes:
  db_data: {}
  wordpress_data: {}
  
3、创建并启动WordPress容器
[root@manager my_wordpress]# docker-compose up -d
WARNING: The Docker Engine you're using is running in swarm mode.

Compose does not use swarm mode to deploy services to multiple nodes in a swarm. All containers will be scheduled on the current node.

To deploy your application across the swarm, use `docker stack deploy`.

Creating network "my_wordpress_default" with the default driver
Creating volume "my_wordpress_db_data" with default driver
Creating volume "my_wordpress_wordpress_data" with default driver
Creating my_wordpress_db_1 ... done
Creating my_wordpress_wordpress_1 ... done

4.web端口访问WordPress
http://localhost:8000

docker-compose使用 docker-compose详解_docker_02