What is the docker run -e equivalent in docker-compose - docker

Question

I can't get environmental variables in a docker-compose file written directly in it to work. A similar configuration with the command line work just fine like this:
docker run --name container_name -d --network=my-net --mount type=bind,src=/Users/t2wu/Documents/Work/Dodo/Intron-Exon_expression/DockerCompose/intronexon_db/mnt_mysql,dst=/var/lib/mysql -e MYSQL_DATABASE=db_name -e MYSQL_USER=username -e MYSQL_PASSWORD=passwd mysql/mysql-server:8.0.13
This is an MySQL instance which sets three environmental variables: MYSQL_DATABASE, MYSQL_USER and MYSQL_PASSWORD. I'm later able to launch bash into it docker exec -it container_name bash and launch the client mysql -u username -p and connects just fine.
However when I write it in a docker-compose.yml:
version: "3.7"
services:
intronexon_db:
image: mysql/mysql-server:8.0.13
volumes:
- type: bind
source: ./intronexon_db/mnt_mysql
target: /var/lib/mysql
environment:
MYSQL_DATABASE: db_name
MYSQL_USER: username
MYSQL_PASSWORD: passwd
networks:
- my-net
networks:
my-net:
driver: bridge
Then when I use the mysql client, it's as if the user doesn't exist. How do I set it so that it is equivalent to the -e flag during docker run?
EDIT
docker-compose --version shows docker-compose version 1.24.1, build 4667896b
EDIT 2
The environmental flag did work. But I run into problem because:
Part of the problem was that it takes MySQL sometime to get the database, username and password setup ready. And I was checking it way too early.
I need to specify localhost for some reason: mysql --host=localhost -u user -p. Specifying 127.0.0.1 will not work.
For some unknown reason the example stack.yml from the official docker image did not have to specify --host when the adminer container is run. If I wipe out the adminer, then --host flag needs to be given.
Sometimes MySQL daemon will stop. It might has to do with my mount target /var/lib/mysql but I'm not certain.
command: --default-authentication-plugin=mysql_native_password is actually significant. I don't know why when I did docker run I didn't need to do anything about this.

Answer 1

docker-compose accept both types of ENVs either an array or a dictionary, better to double or try both approaches.
environment
Add environment variables. You can use either an array or a
dictionary. Any boolean values; true, false, yes no, need to be
enclosed in quotes to ensure they are not converted to True or False
by the YML parser.
Environment variables with only a key are resolved to their values on
the machine Compose is running on, which can be helpful for secret or
host-specific values.
environment:
RACK_ENV: development
SHOW: 'true'
SESSION_SECRET:
or
environment:
- RACK_ENV=development
- SHOW=true
- SESSION_SECRET
Might be something with docker-compose version as it working fine with 3.1. as the offical image suggested, so Better to try offical image docker-compose.yml
version: '3.1'
services:
db:
image: mysql
command: --default-authentication-plugin=mysql_native_password
restart: always
environment:
MYSQL_ROOT_PASSWORD: example
Also, better to debug such cases where everything seems correct but some minor syntax is missing. you can test it before working with DB.
version: "3.7"
services:
intronexon_db:
image: alpine
environment:
MYSQL_DATABASE: myDb
command: tail -f /dev/null
run docker-compose up
Now test and debug in testing enviroment.
docker exec -it composeenv_intronexon_db_1 ash -c "printenv"

Answer 2

the environment params in your yml need the - in front of them could be the likely culprit
version: "3.7"
services:
intronexon_db:
image: mysql/mysql-server:8.0.13
volumes:
- ./intronexon_db/mnt_mysql:/var/lib/mysql
environment:
- MYSQL_DATABASE: db_name
- MYSQL_USER: username
- MYSQL_PASSWORD: passwd
networks:
- my-net
networks:
my-net:
driver: bridge