使用Fig编排Docker

docker

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 2017/09/04   Share

编排

编排是一个没有严格定义的概念，大致描述的就是自动配置，协作和管理服务的过程，在Docker的世界里，编排用来描述一组实践过程，这个过程运行多个多个容器里的应用，通过将这些容器链接起来，快速构建出生产环境与开发环境。

Fig

简单的容器编排，目前Fig团队已经加入了Docker公司，Fig通过配置fig.yml来快速构建基于Docker的复杂应用，容器间通过某些方法指定一些运行的属性来和其他容器的产生交互。

安装Fig

Fig由python编写，所以我门可以通过PYPI源来安装fig。

1	~]# pip install fig

构建应用

构建镜像

~]# mkdir figapp
~]# cd figapp
~]# vim Dockerfile
FROM python:latest
MAINTAINER Jusene

RUN pip install flask redis

~]# docker build -t flask:v1 .

提供web服务程序

~]# vim app.py
#-*- coding=utf8 -*-

from flask import Flask
from redis import Redis

app=Flask(__app__)
redis=Redis(host="db",port=6379)

@app.route('/')
def hello():
	redis.incr('hits')
	return "Hello Docker Reader,You had Hit {0} times!".format(int(redis.get('hits')))

if __name__ == "__main__":
	app.run(host="0.0.0.0",debug=True)

编写fig.yml

~]# vim fig.yml
---
web:
	image: flask:v1
	command: python /figapp/app.py
	ports:
		- "5000:5000"
	volumes:
		- .:/figapp
	links:
		- redis:db
redis:
	image: redis:latest
	environment:

启动fig

~]# fig up                             注意必须在fig.yml下运行
Recreating figapp_redis_1...
Recreating figapp_web_1...
Attaching to figapp_redis_1, figapp_web_1
redis_1 | 1:C 31 Aug 16:22:04.209 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
redis_1 | 1:C 31 Aug 16:22:04.210 # Redis version=4.0.1, bits=64, commit=00000000, modified=0, pid=1, just started
redis_1 | 1:C 31 Aug 16:22:04.210 # 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 31 Aug 16:22:04.214 * Running mode=standalone, port=6379.
redis_1 | 1:M 31 Aug 16:22:04.214 # 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 31 Aug 16:22:04.214 # Server initialized
redis_1 | 1:M 31 Aug 16:22:04.214 # 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 31 Aug 16:22:04.215 # WARNING you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled.
redis_1 | 1:M 31 Aug 16:22:04.215 * DB loaded from disk: 0.000 seconds
redis_1 | 1:M 31 Aug 16:22:04.215 * Ready to accept connections
web_1   |  * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)
web_1   |  * Restarting with stat
web_1   |  * Debugger is active!
web_1   |  * Debugger PIN: 264-973-293

~]# fig up -d  #守护模式

测试应用
1
~]# curl 10.211.55.6:5000
2
Hello Docker Reader,You had Hit 1 times!
3
~]# curl 10.211.55.6:5000
4
Hello Docker Reader,You had Hit 2 times!
因为在flask启动的时候启用debug，所以在修改代码后会自动重载代码，一个快速docker开发环境。

查看docker

~]# docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
745acf95b6cb        flask               "python /figapp/app.p"   4 minutes ago       Up 4 minutes        0.0.0.0:5000->5000/tcp   figapp_web_1
96cb74bd5f45        redis:latest        "docker-entrypoint.sh"   4 minutes ago       Up 4 minutes        6379/tcp                 figapp_redis_1
~]# fig ps
 Name                   Command               State           Ports          
--------------------------------------------------------------------------------
figapp_redis_1   docker-entrypoint.sh redis ...   Up      6379/tcp               
figapp_web_1     python /figapp/app.py            Up      0.0.0.0:5000->5000/tcp 
~]# fig -h
Fast, isolated development environments using Docker.

Usage:
  fig [options] [COMMAND] [ARGS...]
  fig -h|--help

Options:
  --verbose                 Show more output
  --version                 Print version and exit
  -f, --file FILE           Specify an alternate fig file (default: fig.yml)
  -p, --project-name NAME   Specify an alternate project name (default: directory name)

Commands:
  build     Build or rebuild services
  help      Get help on a command
  kill      Kill containers
  logs      View output from containers
  port      Print the public port for a port binding
  ps        List containers
  pull      Pulls service images
  rm        Remove stopped containers
  run       Run a one-off command
  scale     Set number of containers for a service
  start     Start services
  stop      Stop services
  restart   Restart services
  up        Create and start containers

整个过程类似：

1	~]# docker run -d --name figapp_redis_1 redis:latest
2	~]# docker run -d --name figapp_web_1 -v .:/figapp/ -p 5000:5000 --link redis:db flask:v1 python /figapp/app.py

还有fig.yml可以与Dockfile一起使用来构建应用：

~]# vim fig.yml
---
web:
	build: /root/figapp/              #指定Dockerfile所在的目录         
	command: python /figapp/app.py
	ports:
		- "5000:5000"
	volumes:
		- .:/figapp
	links:
		- redis:db
redis:
	image: redis:latest
	environment:                       #指定redis的环境变量

Fig官网链接：http://www.fig.sh/index.html

原文作者：Zhang Jusene

原文链接：http://jusene.github.io/2017/09/04/docker-fig/

发表日期：September 4th 2017, 9:51:58 pm

更新日期：November 30th 2019, 1:55:46 am

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CATALOG

1. 编排
2. Fig
1. 2.1. 安装Fig
2. 2.2. 构建应用



1	~]# mkdir figapp
2	~]# cd figapp
3	~]# vim Dockerfile
4	FROM python:latest
5	MAINTAINER Jusene
6
7	RUN pip install flask redis
8
9	~]# docker build -t flask:v1 .

1	~]# vim app.py
2	#-- coding=utf8 --
3
4	from flask import Flask
5	from redis import Redis
6
7	app=Flask(__app__)
8	redis=Redis(host="db",port=6379)
9
10	@app.route('/')
11	def hello():
12	redis.incr('hits')
13	return "Hello Docker Reader,You had Hit {0} times!".format(int(redis.get('hits')))
14
15	if __name__ == "__main__":
16	app.run(host="0.0.0.0",debug=True)

1	~]# vim fig.yml
2	---
3	web:
4	image: flask:v1
5	command: python /figapp/app.py
6	ports:
7	- "5000:5000"
8	volumes:
9	- .:/figapp
10	links:
11	- redis:db
12	redis:
13	image: redis:latest
14	environment:

1	~]# fig up 注意必须在fig.yml下运行
2	Recreating figapp_redis_1...
3	Recreating figapp_web_1...
4	Attaching to figapp_redis_1, figapp_web_1
5	redis_1 \| 1:C 31 Aug 16:22:04.209 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
6	redis_1 \| 1:C 31 Aug 16:22:04.210 # Redis version=4.0.1, bits=64, commit=00000000, modified=0, pid=1, just started
7	redis_1 \| 1:C 31 Aug 16:22:04.210 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
8	redis_1 \| 1:M 31 Aug 16:22:04.214 * Running mode=standalone, port=6379.
9	redis_1 \| 1:M 31 Aug 16:22:04.214 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.
10	redis_1 \| 1:M 31 Aug 16:22:04.214 # Server initialized
11	redis_1 \| 1:M 31 Aug 16:22:04.214 # 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.
12	redis_1 \| 1:M 31 Aug 16:22:04.215 # WARNING you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled.
13	redis_1 \| 1:M 31 Aug 16:22:04.215 * DB loaded from disk: 0.000 seconds
14	redis_1 \| 1:M 31 Aug 16:22:04.215 * Ready to accept connections
15	web_1 \| * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)
16	web_1 \| * Restarting with stat
17	web_1 \| * Debugger is active!
18	web_1 \| * Debugger PIN: 264-973-293
19
20	~]# fig up -d #守护模式

1	~]# curl 10.211.55.6:5000
2	Hello Docker Reader,You had Hit 1 times!
3	~]# curl 10.211.55.6:5000
4	Hello Docker Reader,You had Hit 2 times!

1	~]# docker ps
2	CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
3	745acf95b6cb flask "python /figapp/app.p" 4 minutes ago Up 4 minutes 0.0.0.0:5000->5000/tcp figapp_web_1
4	96cb74bd5f45 redis:latest "docker-entrypoint.sh" 4 minutes ago Up 4 minutes 6379/tcp figapp_redis_1
5	~]# fig ps
6	Name Command State Ports
7	--------------------------------------------------------------------------------
8	figapp_redis_1 docker-entrypoint.sh redis ... Up 6379/tcp
9	figapp_web_1 python /figapp/app.py Up 0.0.0.0:5000->5000/tcp
10	~]# fig -h
11	Fast, isolated development environments using Docker.
12
13	Usage:
14	fig [options] [COMMAND] [ARGS...]
15	fig -h\|--help
16
17	Options:
18	--verbose Show more output
19	--version Print version and exit
20	-f, --file FILE Specify an alternate fig file (default: fig.yml)
21	-p, --project-name NAME Specify an alternate project name (default: directory name)
22
23	Commands:
24	build Build or rebuild services
25	help Get help on a command
26	kill Kill containers
27	logs View output from containers
28	port Print the public port for a port binding
29	ps List containers
30	pull Pulls service images
31	rm Remove stopped containers
32	run Run a one-off command
33	scale Set number of containers for a service
34	start Start services
35	stop Stop services
36	restart Restart services
37	up Create and start containers

1	~]# vim fig.yml
2	---
3	web:
4	build: /root/figapp/ #指定Dockerfile所在的目录
5	command: python /figapp/app.py
6	ports:
7	- "5000:5000"
8	volumes:
9	- .:/figapp
10	links:
11	- redis:db
12	redis:
13	image: redis:latest
14	environment: #指定redis的环境变量