什么是Docker-Compose？
Compose 是一个用于定义和运行多容器 Docker 应用程序的工具，俗称容器编排。使用 Compose，您可以使用 YAML 文件来配置应用程序的服务。然后，使用一个命令，您可以从您的配置中创建并启动所有服务。要了解有关 Compose 的所有功能的更多信息，请参阅功能列表。
Compose 适用于所有环境：生产、登台、开发、测试以及 CI 工作流程。您可以在常见用例中了解有关每个案例的更多信息。
使用 Compose 基本上是一个三步过程：
- 使用 a 定义您的应用程序的环境，
Dockerfile以便可以在任何地方复制它。 - 定义构成您的应用程序的服务，
docker-compose.yml以便它们可以在隔离环境中一起运行。 - 运行
docker compose up，Docker compose 命令启动并运行您的整个应用程序。您也可以docker-compose up使用 Compose Standalone（docker-compose二进制）运行。
docker-compose.yml文件开起来像这样
version: "3.9" # optional since v1.27.0
services:
web:
build: .
ports:
- "8000:5000"
volumes:
- .:/code
- logvolume01:/var/log
depends_on:
- redis
redis:
image: redis
volumes:
logvolume01: {}
安装Docker-Compose
Debin/Ubuntu
sudo apt-get update
sudo apt-get install docker-compose-plugin
#卸载
sudo apt-get remove docker-compose-plugin
Centos
sudo yum update
sudo yum install docker-compose-plugin
#卸载
sudo yum remove docker-compose-plugin
Alpine
apk update
apk add docker-compose
#卸载
apk del docker-compose
其他Linux下载二进制文件安装
curl -SL https://github.com/docker/compose/releases/download/v2.10.2/docker-compose-linux-x86_64 -o /usr/local/bin/docker-compose
#卸载
rm /usr/local/lib/docker/cli-plugins/docker-compose
验证是否安装成功 docker-compose version
docker-compose
localhost:~# docker-compose version
docker-compose version 1.29.2, build unknown
docker-py version: 5.0.3
CPython version: 3.10.5
OpenSSL version: OpenSSL 1.1.1q 5 Jul 2022
Demo演示
创建项目文件夹
#为项目创建一个文件夹并进入
mkdir composetest
cd composetest
编写一个程序文件 app.py
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)
if __name__ == '__main__':
app.run(host='0.0.0.0',port=5000)
编写依赖文件 requirements.txt
flask
redis
编写Dockerfile
# syntax=docker/dockerfile:1
#导入python:3.7
FROM python:3.7
#设置工作路径为/code
WORKDIR /code
#拷贝依赖列表
COPY requirements.txt requirements.txt
#安装依赖
RUN pip install -r requirements.txt-i "http://mirrors.aliyun.com/pypi/simple" --trusted-host "mirrors.aliyun.com"
#公开端口
EXPOSE 5000
#复制当前目录下所有文件
COPY . .
#运行
CMD ["python","app.py"]
编写 docker-compose.yml
version: "3.9"
services:
web:
build: .
ports:
- "8000:5000"
volumes:
- .:/code
redis:
image: "redis:alpine"
#version: "3.9" 指定Docker-compose最低运行版本
#services: 定义服务 web 和 redis
#web 服务又当前目录下的Dockerfile文件构建并将5000端口映射到主机8000端口并将工作目录挂载到主机
#redis 指定镜像为 redis:alpine
在您的项目目录中，通过运行docker compose up
localhost:~/test# docker-compose up
Creating network "test_default" with the default driver
Creating test_web_1 ... done
Creating test_redis_1 ... done
Attaching to test_web_1, test_redis_1
redis_1 | 1:C 14 Sep 2022 05:31:15.221 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
redis_1 | 1:C 14 Sep 2022 05:31:15.221 # Redis version=6.2.1, bits=64, commit=00000000, modified=0, pid=1, just started
redis_1 | 1:C 14 Sep 2022 05:31:15.221 # 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 14 Sep 2022 05:31:15.222 * monotonic clock: POSIX clock_gettime
redis_1 | 1:M 14 Sep 2022 05:31:15.223 * Running mode=standalone, port=6379.
redis_1 | 1:M 14 Sep 2022 05:31:15.223 # Server initialized
redis_1 | 1:M 14 Sep 2022 05:31:15.223 # 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 14 Sep 2022 05:31:15.223 * Ready to accept connections
web_1 | * Serving Flask app 'app'
web_1 | * Debug mode: off
web_1 | WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.
web_1 | * Running on all addresses (0.0.0.0)
web_1 | * Running on http://127.0.0.1:5000
web_1 | * Running on http://172.21.0.3:5000
web_1 | Press CTRL+C to quit
#启动成功
在后台运行 docker-compose up -d
localhost:~/test# docker-compose up -d
Starting test_redis_1 ... done
Starting test_web_1 ... done
停止运行
localhost:~/test# docker-compose down
Stopping test_web_1 ... done
Stopping test_redis_1 ... done
Removing test_web_1 ... done
Removing test_redis_1 ... done
Removing network test_default
docker-compose项目 快捷指令
docker-compose up -d #启动并后台运行
docker-compose stop #停止
docker-compose strat #开始
docker-compose restart #重启项目
docker-compose down #停止并删除容器
docker-compose down --volumes #删除挂载卷
Docker-Compose文件 编写规则
Docker-Compose文件编写规则繁琐且关键字繁多，核心为三层结构
#1.version 定义版本信息，根据服务器Docker引擎版本填写
version： '3.8'
#2.service 用于定以容器信息
service：
web-Core： #定义一个服务
container_name: my-web-container #容器名称
image：python：3.8.10 #使用镜像
restart: always #容器重启策略
ports: #公开端口
- "8000:5000"
volumes: #挂载卷，可以匿名挂载
- web-Core:/root/app
#容器启动后运行命令，可覆盖Dockerfile内的CMD
command: uwsgi --ini uwsgi.ini #等同command: ["uwsgi","--ini","uwsgi.ini"]
devices: #映射设备
- "/dev/ttyUSB0:/dev/ttyUSB0"
- "/dev/sda:/dev/xvda:rwm"
dns: #设置容器内DNS地址
- 114.114.114.114
- 8.8.8.8
extends: #延迟启动，等待别的容器启动完成
service:
- mysql
environment: #设置容器内环境变量
- RACK_ENV=development
- SHOW=true
- USER_INPUT
external_links: #链接外部容器
- redis
- database:mysql
- database:postgresql
extra_hosts: #链接外部服务器
- "somehost:162.242.195.82"
- "otherhost:50.31.209.229"
mysql:
image:mysql:5.7
environment:
- MYSQL_ROOT_PASSWORD=passwd
volumes:
- mysql:/var/lib/mysql
#3.其他配置，项目不需要也可以不填写
volumes： #定义挂载卷信息
mysql:
web-Core:
networks： #定义网络信息
configs： #定义配置信息
Docker-Compose文件 其他撰写操作
静态分配IP地址
services:
frontend:
image: awesome/webapp
networks: #指定网络名称并设置ip地址
front-tier:
ipv4_address: 172.16.238.10
ipv6_address: 2001:3984:3989::10
networks: #定义一个名为front-tier的网络
front-tier:
ipam:
driver: default
config:
- subnet: "172.16.238.0/24"
- subnet: "2001:3984:3989::/64"
桥接到物理网卡
services:
app:
image: busybox
command: top
networks:
app_net:
link_local_ips:
- 57.123.22.11
- 57.123.22.13
networks:
app_net: #bridge #网桥模式
driver: bridge
Docker-Compose 案例讲解
owncloud + mariadb
version: '3.1'
services:
owncloud:
image: owncloud
restart: always
ports:
- 8080:80
mysql:
image: mariadb
restart: always
environment:
MYSQL_ROOT_PASSWORD: passwd
#定义一个owncloud服务，镜像为owncloud最新版，容器始终启动，映射容器80端口到主机8080。
#定义一个mysql服务，镜像为mariadb最新版，容器始终启动，设置一个环境变量为数据库密码。
werdpress + mysql
version: '3.1'
services:
wordpress:
image: wordpress
restart: always
ports:
- 8080:80
environment:
WORDPRESS_DB_HOST: db
WORDPRESS_DB_USER: exampleuser
WORDPRESS_DB_PASSWORD: examplepass
WORDPRESS_DB_NAME: exampledb
volumes:
- wordpress:/var/www/html
db:
image: mysql:5.7
restart: always
environment:
MYSQL_DATABASE: exampledb
MYSQL_USER: exampleuser
MYSQL_PASSWORD: examplepass
MYSQL_RANDOM_ROOT_PASSWORD: '1'
volumes:
- db:/var/lib/mysql
volumes:
wordpress:
db:
#定义两个服务wordpress和db
#wordpress映射80端口到主机8080，设置环境变量为数据库信息挂载/var/www/html目录到wordpress挂载卷
#db设置环境变量为数据库名称/用户名/数据库密码/root密码//var/lib/mysql目录到db挂载卷
nextcloud+mariadb+nginx
version: '2'
volumes:
nextcloud:
db:
services:
db:
image: mariadb:10.5
restart: always
command: --transaction-isolation=READ-COMMITTED --binlog-format=ROW
volumes:
- db:/var/lib/mysql
environment:
- MYSQL_ROOT_PASSWORD=
- MYSQL_PASSWORD=
- MYSQL_DATABASE=nextcloud
- MYSQL_USER=nextcloud
app:
image: nextcloud:fpm
restart: always
links:
- db
volumes:
- nextcloud:/var/www/html
environment:
- MYSQL_PASSWORD=
- MYSQL_DATABASE=nextcloud
- MYSQL_USER=nextcloud
- MYSQL_HOST=db
web:
image: nginx
restart: always
ports:
- 8080:80
links:
- app
volumes:
- ./nginx.conf:/etc/nginx/nginx.conf:ro
volumes_from:
- app
mysql+adminer
# Use root/example as user/password credentials
version: '3.1'
services:
adminer:
image: adminer
restart: always
ports:
- 8080:8080
db:
image: mysql:5.6
restart: always
environment:
MYSQL_ROOT_PASSWORD: example
#数据库设置环境变量 ROOT密码
#adminer 容器自动启动
mariadb+phpmyadmin
version: '3.1'
services:
db:
image: mariadb:10.3
restart: always
environment:
MYSQL_ROOT_PASSWORD: passwd
phpmyadmin:
image: phpmyadmin
restart: always
ports:
- 38080:80