Docker容器配置管理
Set environment variables (-e, --env, --env-file) $ docker run -e MYVAR1 --env MYVAR2=foo --env-file ./env.list ubuntu bash Use the -e, --env, and --env-file flags to set simple (non-array) environment variables in the container you’re running, or overwrite variables that are defined in the Dockerfile of the image you’re running. You can define the variable and its value when running the container: $ docker run --env VAR1=value1 --env VAR2=value2 ubuntu env | grep VAR VAR1=value1 VAR2=value2 You can also use variables that you’ve exported to your local environment: export VAR1=value1 export VAR2=value2 $ docker run --env VAR1 --env VAR2 ubuntu env | grep VAR VAR1=value1 VAR2=value2 When running the command, the Docker CLI client checks the value the variable has in your local environment and passes it to the container. If no = is provided and that variable is not exported in your local environment, the variable won’t be set in the container. You can also load the environment variables from a file. This file should use the syntax <variable>=value (which sets the variable to the given value) or <variable> (which takes the value from the local environment), and # for comments. $ cat env.list # This is a comment VAR1=value1 VAR2=value2 USER $ docker run --env-file env.list ubuntu env | grep VAR VAR1=value1 VAR2=value2 USER=denis
通过env查看抓取环境变量
测试案例
root@playbook-master:~/test# cat Dockerfile
1 FROM ubuntu:16.04 2 3 RUN apt update && apt install -y python-pip lrzsz 4 5 ADD . /root 6 7 WORKDIR /root 8 9 CMD ["python","env_docker.py"]
root@playbook-master:~/test# cat redis.conf
{{var1}}
{{var2}}
{{password_redis}}
root@playbook-master:~/test# cat var.txt
var1=docker
var2=redis
password_redis=123456
__config_location=/root/redis.conf
root@playbook-master:~/test# docker run --name env1 -d --env-file ./var.txt env:test
eb6eb002f1d03d783d49fd17b872abf96370323d50f00fafba1fed4e23e91141
root@playbook-master:~/test# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
eb6eb002f1d0 env:test "python env_docker.py" 2 seconds ago Up 1 second env1
root@playbook-master:~/test# docker exec -it env1 /bin/bash
root@eb6eb002f1d0:~# cat redis.conf
docker
redis
123456
python 处理脚本Env_docker.py
1 # -*- coding:utf-8 -*- 2 3 #!/usr/bin/python 4 5 import os 6 7 import re 8 9 import time 10 11 def alter(file): 12 13 dict = os.environ 14 15 16 17 file_data = "" 18 19 with open(file,"r") as f: 20 21 for line in f: 22 23 for key in dict.keys(): 24 25 if key in dict.keys(): 26 27 keya = "{{"+key+"}}" 28 29 line = line.replace(keya,dict[key]) 30 31 file_data += line 32 33 with open(file,"w") as f: 34 35 f.write(file_data) 36 37 38 39 dict=os.environ 40 41 filenames = dict['__config_location'] 42 43 filenames = filenames.split(',') 44 45 for filename in filenames: 46 47 print(filename) 48 49 alter(filename) 50 51 time.sleep(60) #测试添加入env_docker.py脚本
shell处理脚本（ubuntu /bin/sh不支持数组功能，要用/bin/bash)
1 #!/bin/bash 2 3 deal(){ 4 5 key=($(env|awk -F= '{print $1}')) 6 7 value=($(env|awk -F= '{print $2}')) 8 9 num=$(env|wc -l) 10 11 for ((i=0;i<$num;i++)) 12 13 do 14 15 key1=${key[$i]} 16 17 keya="{{"$key1"}}" 18 19 value1=${value[$i]} 20 21 grep $keya $file >/dev/null 22 23 if [ $? -eq 0 ]; 24 25 then 26 27 sed -i "s/$keya/$value1/g" $file 28 29 fi 30 31 done 32 33 } 34 35 for file in `echo ${__config_location}|awk -F, '{for(i=1;i<=NF;i++){print $i;}}'` 36 37 do 38 39 deal 40 41 done