Docker系列之十：Docker Compose的使用

系列链接

简介

在之前运行一个容器必须使用一段命令如：docker run -itd -p 80:80 -v /var/data/:/var/data/ --volume-from cong1 --net congnet --name mynginx nginx，每次运行都需要写这么一段，有点烦，接下来我们使用Docker compose来解决这个问题，其实run 后面的都算配置，而yaml文件是目前写配置文件的利器。

使用Docker compose，可以用一个YAML文件定义一组要启用的容器，以及容器运行的属性，Docker compose称这些容器为“服务”。

安装Docker Compose

下载最新的docker-compose,并安装到文件夹/usr/local/bin/docker-compose 下。

sudo curl -L "https://github.com/docker/compose/releases/download/1.23.1/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

修改权限，让它变成得可执行

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

检查版本，出现如下界面，说明安装成功了

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose -v
docker-compose version 1.23.1, build b02f1306

使用Docker Compose创建一个image，并运行

创建一个文件夹，像下面这样。

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# ls
docker-compose.yml  Dockerfile  index.html

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# cat Dockerfile
FROM nginx
WORKDIR /usr/share/nginx/html
COPY . .
#Volume /home/app
EXPOSE 80

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# cat docker-compose.yml
---
version: '3'
services:
  web:
    build: "/home/cong/DockerDemo/"
    ports:
     - "5000:80"
  redis:
    image: "redis"
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# cat index.html
<h1>Hello world</h1>
<h2>my greet</h2>

从上可以看出里面有两个服务:web 和 redis，运行如下命令进行构建docker image.

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose build
redis uses an image, skipping
Building web
Step 1/4 : FROM nginx
 ---> dbfc48660aeb
Step 2/4 : WORKDIR /usr/share/nginx/html
 ---> Using cache
 ---> 49eb0195ae40
Step 3/4 : COPY . .
 ---> 45a1d6022ef6
Step 4/4 : EXPOSE 80
 ---> Running in e18fcf899aff
Removing intermediate container e18fcf899aff
 ---> 36f9a746361b
Successfully built 36f9a746361b
Successfully tagged dockerdemo_web:latest

这里由于redis服务中使用的是的redis镜像，这里显示为跳过，只生成一个镜像，这个镜像的名字是以你的当前文件夹名+服务名命名的，生成出来的镜像如下：

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker images
REPOSITORY              TAG                 IMAGE ID            CREATED             SIZE
dockerdemo_web          latest              36f9a746361b        2 minutes ago       109MB

运行如下命令，运行容器，-d 表示detached在后台运行。

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose up -d
Starting dockerdemo_web_1_4b7b83909e42   ... done
Starting dockerdemo_redis_1_dfd3e5c242ff ... done

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
da2cb8d44ee5        dockerdemo_web      "nginx -g 'daemon of…"   21 seconds ago      Up 3 seconds        0.0.0.0:5000->80/tcp     dockerdemo_web_1_4b7b83909e42
a8b63ebd622d        redis               "docker-entrypoint.s…"   21 seconds ago      Up 2 seconds        6379/tcp                 dockerdemo_redis_1_dfd3e5c242ff


root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker network ls
NETWORK ID          NAME                 DRIVER              SCOPE
0a5324c3bd83        bridge               bridge              local
f04d01cfd231        dockerdemo_default   bridge              local
fa685cfac4f3        host                 host                local
22f6181538a9        none                 null                local

发现这两容器都运行起来了，而且它们都在网络dockerdemo_default中。

接下来我们修改docker-compose.yml文件，将当前路径下的文件挂载到容器中。yaml文件内容如下，然后再执行docker -compose up命令，它会rebuild image, 最终看到文件夹挂载成功了。

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# cat docker-compose.yml
---
version: '3'
services:
  web:
    volumes:
     - .:/usr/share/nginx/html
    build: "/home/cong/DockerDemo/"
    ports:
     - "5000:80"
  redis:
    image: "redis"

#修改当前路径里index.html文件的内容
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# echo "<h1>hello</h1>" > index.html

#再执行docker-compose up，它会自动更新镜像并运行容器
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose up -d
dockerdemo_redis_1_dfd3e5c242ff is up-to-date
Recreating dockerdemo_web_1_4b7b83909e42 ... done

#检查是否挂载成功
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# curl localhost:5000
<h1>hello</h1>

执行docker-compose ps 看看通过docker-compose 运行起来的容器

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose ps
             Name                            Command               State          Ports
-----------------------------------------------------------------------------------------------
dockerdemo_redis_1_dfd3e5c242ff   docker-entrypoint.sh redis ...   Up      6379/tcp
dockerdemo_web_1_4b7b83909e42     nginx -g daemon off;             Up      0.0.0.0:5000->80/tcp


root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
e0020488cb04        dockerdemo_web      "nginx -g 'daemon of…"   17 hours ago        Up 17 hours         0.0.0.0:5000->80/tcp     dockerdemo_web_1_4b7b83909e42
a8b63ebd622d        redis               "docker-entrypoint.s…"   17 hours ago        Up 17 hours         6379/tcp                 dockerdemo_redis_1_dfd3e5c242ff
78761e99c06f        nginx               "nginx -g 'daemon of…"   45 hours ago        Up 45 hours         0.0.0.0:80->80/tcp       mynginx
1b25aef5f610        redis               "docker-entrypoint.s…"   8 days ago          Up 8 days           0.0.0.0:6379->6379/tcp   kind_curran

如果想要执行某个服务里命令，或者说执行某个容器里的命令呢，下面是查看web服务里的环境变量

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose run web env
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=5435187b75a1
TERM=xterm
NGINX_VERSION=1.15.5-1~stretch
NJS_VERSION=1.15.5.0.2.4-1~stretch
HOME=/root

使用Docker Compose停止服务

直接看下面的命令

#停止服务
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose down
Stopping dockerdemo_web_1_4b7b83909e42   ... done
Stopping dockerdemo_redis_1_dfd3e5c242ff ... done
Removing dockerdemo_redis_run_1_636fb680637e ... done
Removing dockerdemo_web_run_1_1e57ca097b87   ... done
Removing dockerdemo_web_1_4b7b83909e42       ... done
Removing dockerdemo_redis_1_dfd3e5c242ff     ... done
Removing network dockerdemo_default

root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose ps
Name   Command   State   Ports
------------------------------
#服务停止后，但镜像还在
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker images
REPOSITORY              TAG                 IMAGE ID            CREATED             SIZE
dockerdemo_web          latest              36f9a746361b        17 hours ago        109MB
redis                   latest              1babb1dde7e1        3 weeks ago         94.9MB
node                    latest              a2b9536415c2        4 weeks ago         674MB
nginx                   latest              dbfc48660aeb        4 weeks ago         109MB

#服务停止后，但卷还在
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker volume ls
DRIVER              VOLUME NAME
local               1ff8ca8ce28be5851d217134e90b74cb24c35035284ce93d83363085e37adac4

# 移除卷
root@iZbp13z6cxj72rb7bxf0smZ:/home/cong/DockerDemo# docker-compose down --volumes
Removing network dockerdemo_default
WARNING: Network dockerdemo_default not found.

到这里就结束，这里只演示了使用docker-compose最基本的用法，如深度学习，请参考如下链接。

参考链接

https://docs.docker.com/compose/reference/overview/