二、通过Docker-compose来实现(Docker官网实例)

（1）首先第一步需要安装Docker-compose

 sudo curl -L "https://github.com/docker/compose/releases/download/1.29.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

 sudo chmod +x /usr/local/bin/docker-compose

sudo ln -s /usr/local/bin/docker-compose /usr/bin/docker-compose

(2) 编辑docker-compose.yaml

version: '3'
services:
  web:
    build: .
    ports:
      - "5000:5000"
    networks:
      - app-net

  redis:
    image: "redis:alpine"
    networks:
      - app-net

networks:
  app-net:
    driver: bridge

docker-compose up -d 

总结：一二节是实例 约等于官网的实例

详解docker-compose.yml文件

(1)version: ‘3’

表示docker-compose的版本

(2)services

一个service表示一个container

(3)networks

相当于docker network create app-net

(4)volumes

相当于-v v1:/var/lib/mysql

(5)image

表示使用哪个镜像，本地build则用build，远端则用image

(6)ports

相当于-p 8080:8080

(7)environment

相当于-e

docker-compose常见操作(1)查看版本

docker-compose version

(2)根据yml创建service

docker-compose up

指定yaml：docker-compose up -f xxx.yaml

后台运行：docker-compose up

(3)查看启动成功的service

docker-compose ps

也可以使用docker ps

(4)查看images

docker-compose images

(5)停止/启动service

docker-compose stop/start

(6)删除service[同时会删除掉network和volume]

docker-compose down

(7)进入到某个service

docker-compose exec redis sh

scale扩缩容

(1)修改docker-compose.yaml文件，主要是把web的ports去掉，不然会报错

version: '3'
services:
  web:
    build: .
    networks:
      - app-net

  redis:
    image: "redis:alpine"
    networks:
      - app-net

networks:
  app-net:
    driver: bridge

(2)创建service

docker-compose up -d

(3)若要对python容器进行扩缩容

docker-compose up --scale web=5 -d
docker-compose ps
docker-compose logs web

从之前的操作单机向操作集群转变