docker学习6-docker-compose容器集群编排
前言
实际工作中我们部署一个应用,一般不仅仅只有一个容器,可能会涉及到多个,比如用到数据库,中间件MQ,web前端和后端服务,等多个容器。
我们如果一个个去启动应用,当项目非常多时,就很难记住了,所有需要一个配置文件,负责实现对Docker容器集群的快速编排。
docker-compose
简介
Docker-Compose项目是Docker官方的开源项目,负责实现对Docker容器集群的快速编排。
Docker-Compose将所管理的容器分为三层,分别是工程(project),服务(service)以及容器(container)。
Docker-Compose运行目录下的所有文件(docker-compose.yml,extends文件或环境变量文件等)组成一个工程,若无特殊指定工程名即为当前目录名。一个工程当中可包含多个服务,每个服务中定义了容器运行的镜像,参数,依赖。一个服务当中可包括多个容器实例,Docker-Compose并没有解决负载均衡的问题,因此需要借助其它工具实现服务发现及负载均衡。
Docker-Compose的工程配置文件默认为docker-compose.yml,可通过环境变量COMPOSE_FILE或-f参数自定义配置文件,其定义了多个有依赖关系的服务及每个服务运行的容器。
安装
docker-compose使用pip安装即可
pip install docker-compose
使用docker-compose version查看版本
[root@yoyo ~]# docker-compose version
/usr/lib/python2.7/site-packages/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.22) or chardet (2.2.1) doesn't match a supported version!
RequestsDependencyWarning)
docker-compose version 1.24.1, build 4667896
docker-py version: 3.7.3
CPython version: 2.7.5
OpenSSL version: OpenSSL 1.0.1e-fips 11 Feb 2013
[root@yoyo ~]#
实例
docker-compose.yml文件
docker-compose已经安装成功,接下来去https://hub.docker.com上找个项目部署练练手,项目地址:https://hub.docker.com/r/easymock/easymock
docker-compose 文件内容
version: '3'
services:
mongodb:
image: mongo:3.4
volumes:
# ./data/db 数据库文件存放地址,根据需要修改为本地地址
- './data/db:/data/db'
networks:
- easy-mock
restart: always
redis:
image: redis:4.0.6
command: redis-server --appendonly yes
volumes:
# ./data/redis redis 数据文件存放地址,根据需要修改为本地地址
- './data/redis:/data'
networks:
- easy-mock
restart: always
web:
image: easymock/easymock:1.6.0
command: /bin/bash -c "npm start"
ports:
- 7300:7300
volumes:
# 日志地址,根据需要修改为本地地址
- './logs:/home/easy-mock/easy-mock/logs'
# 配置地址,请使用本地配置地址替换
# - './production.json:/home/easy-mock/easy-mock/config/production.json'
networks:
- easy-mock
restart: always
networks:
easy-mock:
在本地新建一个文件夹/root/easymock,接着新建文件docker-compose.yml,把上面的内容写入到这个文件里,如下步骤
[root@yoyo ~]# mkdir /root/easymock
[root@yoyo ~]# cd /root/easymock/
[root@yoyo easymock]# touch docker-compose.yml
[root@yoyo easymock]# vi docker-compose.yml
[root@yoyo easymock]# cat docker-compose.yml
version: '3'
services:
mongodb:
image: mongo:3.4
volumes:
# ./data/db 数据库文件存放地址,根据需要修改为本地地址
- './data/db:/data/db'
networks:
- easy-mock
restart: always
redis:
image: redis:4.0.6
command: redis-server --appendonly yes
volumes:
# ./data/redis redis 数据文件存放地址,根据需要修改为本地地址
- './data/redis:/data'
networks:
- easy-mock
restart: always
web:
image: easymock/easymock:1.6.0
command: /bin/bash -c "npm start"
ports:
- 7300:7300
volumes:
# 日志地址,根据需要修改为本地地址
- './logs:/home/easy-mock/easy-mock/logs'
# 配置地址,请使用本地配置地址替换
# - './production.json:/home/easy-mock/easy-mock/config/production.json'
networks:
- easy-mock
restart: always
networks:
easy-mock:
[root@yoyo easymock]#
docker-compose up启动
使用docker-compose up 指令启动服务,可以看到依次启动三个容器
Creating easymock_redis_1 … done
Creating easymock_mongodb_1 … done
Creating easymock_web_1 … done
[root@yoyo easymock]# docker-compose up
/usr/lib/python2.7/site-packages/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.22) or chardet (2.2.1) doesn't match a supported version!
RequestsDependencyWarning)
Creating network "easymock_easy-mock" with the default driver
Pulling mongodb (mongo:3.4)...
3.4: Pulling from library/mongo
f7277927d38a: Pull complete
8d3eac894db4: Pull complete
edf72af6d627: Pull complete
3e4f86211d23: Pull complete
5747135f14d2: Pull complete
f56f2c3793f6: Pull complete
f8b941527f3a: Pull complete
4000e5ef59f4: Pull complete
b2229b3c9065: Pull complete
63e3700b27e5: Pull complete
a77f0e7057fd: Pull complete
4ea8e2e4c04b: Pull complete
3214e739257b: Pull complete
d05fd2e6729f: Pull complete
Digest: sha256:0264d096073b0a862586cfe9a4a8d1a41e206b447d5f1043f241177d9cc70b7d
Status: Downloaded newer image for mongo:3.4
Pulling redis (redis:4.0.6)...
4.0.6: Pulling from library/redis
c4bb02b17bb4: Pull complete
58638acf67c5: Pull complete
f98d108cc38b: Pull complete
83be14fccb07: Pull complete
5d5f41793421: Pull complete
ed89ff0d9eb2: Pull complete
Digest: sha256:0e773022cd6572a5153e5013afced0f7191652d3cdf9b1c6785eb13f6b2974b1
Status: Downloaded newer image for redis:4.0.6
Pulling web (easymock/easymock:1.6.0)...
1.6.0: Pulling from easymock/easymock
7e6591854262: Pull complete
089d60cb4e0a: Pull complete
9c461696bc09: Pull complete
45085432511a: Pull complete
70a7567bd8cf: Pull complete
0f7e44bf28f5: Pull complete
523067e58a08: Pull complete
35e77c0527fd: Pull complete
0df0b0c81b8b: Pull complete
cd5e5a709bf4: Pull complete
d50e2d78de99: Pull complete
Digest: sha256:37d50204c694eb4e50a7ba66406736bc1ae631e0e230abf77573d5ed154fb5a2
Status: Downloaded newer image for easymock/easymock:1.6.0
Creating easymock_redis_1 ... done
Creating easymock_mongodb_1 ... done
Creating easymock_web_1 ... done
如果看到以下报错,permission denied, open 'logs/2019-08-18-info.log’,给log文件夹加个权限即可
chmod 777 /root/easymock/logs/
web_1 | WARNING: NODE_ENV value of 'production' did not match any deployment config file names.
web_1 | WARNING: See https://github.com/lorenwest/node-config/wiki/Strict-Mode
web_1 | server started at http://0.0.0.0:7300
web_1 | events.js:182
web_1 | throw er; // Unhandled 'error' event
web_1 | ^
web_1 |
web_1 | Error: EACCES: permission denied, open 'logs/2019-08-18-info.log'
web_1 | npm ERR! code ELIFECYCLE
web_1 | npm ERR! errno 1
web_1 | npm ERR! easy-mock@1.6.0 start: `cross-env NODE_ENV=production node app`
web_1 | npm ERR! Exit status 1
web_1 | npm ERR!
web_1 | npm ERR! Failed at the easy-mock@1.6.0 start script.
web_1 | npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
web_1 |
web_1 | npm ERR! A complete log of this run can be found in:
web_1 | npm ERR! /home/easy-mock/.npm/_logs/2019-08-18T15_02_51_366Z-debug.log
接着浏览器输入http://ip:7300/即可访问了
docker-compose挂后台运行
挂后台运行需加-d参数
docker-compose up -d
查看正在启动的docker容器使用docker ps
[root@yoyo easymock]# docker-compose up -d
/usr/lib/python2.7/site-packages/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.22) or chardet (2.2.1) doesn't match a supported version!
RequestsDependencyWarning)
Starting easymock_mongodb_1 ... done
Starting easymock_web_1 ... done
Starting easymock_redis_1 ... done
[root@yoyo easymock]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
026f41a372cf easymock/easymock:1.6.0 "/bin/bash -c 'npm s…" 11 minutes ago Up 7 seconds 0.0.0.0:7300->7300/tcp easymock_web_1
5dbbb2086b1c redis:4.0.6 "docker-entrypoint.s…" 11 minutes ago Up 7 seconds 6379/tcp easymock_redis_1
f4772582dd03 mongo:3.4 "docker-entrypoint.s…" 11 minutes ago Up 7 seconds 27017/tcp easymock_mongodb_1
1d07763a6eaa tomcat "catalina.sh run" 7 weeks ago Up 5 weeks 0.0.0.0:8090->8080/tcp yoyotomcat
37a3b50d151c mysql:5.6 "docker-entrypoint.s…" 7 weeks ago Up 5 weeks 0.0.0.0:3308->3306/tcp mymysql
[root@yoyo easymock]#
docker-compose停止运行
停掉服务使用docker-compose down
docker-compose down
[root@yoyo easymock]# docker-compose down
/usr/lib/python2.7/site-packages/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.22) or chardet (2.2.1) doesn't match a supported version!
RequestsDependencyWarning)
Stopping easymock_web_1 ... done
Stopping easymock_redis_1 ... done
Stopping easymock_mongodb_1 ... done
Removing easymock_web_1 ... done
Removing easymock_redis_1 ... done
Removing easymock_mongodb_1 ... done
Removing network easymock_easy-mock
[root@yoyo easymock]#