docker-compose environment variables
The configurations that must be modified for each deployment are independent from the delivery file, and the original configuration is overwritten by docker-compose.
Record it for reference
[root@test03 test]# cat
version: '2'
services:
mysql:
image: test_db:v1
container_name: xx-mysql
restart: always
networks:
- nets
environment:
- MYSQL_ROOT_PASSWORD=xxx0209
ports:
- 3306:3306
volumes:
- /opt/data/mysql:/var/lib/mysql:z
redis:
image: test_redis:v1
container_name: xx-redis
restart: always
networks:
- nets
ports:
- 6379:6379
admin:
image: test_admin:v1
container_name: xx-admin
restart: always
# Use nets network networks:
- nets
env_file:
- ./.env
environment:
# Refer to environment variables, and finally pass it into the start command of the delivery in the container # Example java -jar -=file:/dev/./urandom -=GMT+08 -Xmx1433m -=http://10.90.2.103:8080 ./ - JAVA_OPTS=-=GMT+08 ${Xmx} -D${inter}
depends_on:
- mysql
- redis
ports:
- ${pub_port}:8015
# Create a custom networknetworks:
nets:
external: false
The name defined by container_name when the application interaction is used by container_name
Xmx,inter,pub_port are the environment variables I use. By looking up the documentation, the variables can be defined in a file, such as defined in .env, as follows:
[root@test03 test]# cat .env # memory Xmx=-Xmx1433m # open ports pub_port=8080 # inter inter==http://10.90.2.103:8080
Notice:
The environment variables defined in env_file and environment are passed to containers instead of environment variables in them.
The environment variable ${VARIABLE:-default} in the reference is defined in .env or exported from the same shell
You can check that the variable has been referenced through the command
[root@test03 test]# docker-compose config
...
environment:
JAVA_OPTS: -=GMT+08 -Xmx1433m -=http://10.90.2.103:8080
...It is recommended that the file name introduced by env_file is .env, it is best not to use other names.
- advantage:
.env file changes will update references in docker-compose in real time, using other names will not update references in docker-compose in real time, and using other names to references in docker-compose will sometimes
WARNING: The DB_DIR variable is not set. Defaulting to a blank string.
- shortcoming:
Customized name is inconvenient
Summarize
The above is personal experience. I hope you can give you a reference and I hope you can support me more.