env-file and MariaDB in docker-compose - docker

Question

I'm trying to set up nextcloud on a Raspberry Pi 3B+ with MariaDB, roughly following this example:
https://github.com/nextcloud/docker/blob/master/.examples/docker-compose/with-nginx-proxy/mariadb/apache/docker-compose.yml
My compose file looks like this:
version: '3'
services:
db:
image: mariadb
env_file:
- pi.env
command: --transaction-isolation=READ-COMMITTED --binlog-format=ROW
restart: always
volumes:
- ${BASE_PATH}/db:/var/lib/mysql
nextcloud:
image: nextcloud:apache
env_file:
- pi.env
restart: always
ports:
- 80:80
- 443:443
volumes:
- ${BASE_PATH}/www:/var/www
depends_on:
- db
environment:
- MYSQL_HOST=db
Then there is the pi.env file:
MYSQL_PASSWORD=secure-password
MYSQL_ROOT_PASSWORD=even-more-secure.password
MYSQL_DATABASE=nextcloud
MYSQL_USER=nextcloud
BASE_PATH=/tmp
After running docker-compose up from the directory the yaml and the env file are sitting in, the two containers start up fine. Alas, the database connection can not be established because the db-container only accepts a blank password (popping up a shell in the container and running mysql -u nextcloud without handing in a password gives me database access). Still, the $MYSQL_ROOT_PASSWORD environment variable can be correctly echoed from the container.
If I start a mariadb-image alone with docker run -e MYSQL_ROOT_PASSWORD=secure-password, everything behaves as expected.
Can someone point me to my mistake?

Answer 1

I finally cured my setup some time ago. Sadly, I can not reconstruct what did the trick anymore (and my git commit messages were not as clear to my future self as I hoped they would be :D).
But it appears to me that exclusively declaring the environment variables for the database password in the pi.env file instead of the docker-compose.yaml did the trick.
My docker-compose.yaml:
services:
db:
image: jsurf/rpi-mariadb
command: --transaction-isolation=READ-COMMITTED --binlog-format=ROW --character-set-server=utf8mb4 --collation-server=utf8mb4_general_ci
restart: always
volumes:
- db:/var/lib/mysql
env_file:
- pi.env
nextcloud:
image: nextcloud:apache
restart: always
container_name: nextcloud
volumes:
- www:/var/www/html
environment:
- VIRTUAL_HOST=${VIRTUAL_HOST}
- LETSENCRYPT_HOST=${VIRTUAL_HOST}
- LETSENCRYPT_EMAIL=${LETSENCRYPT_EMAIL}
- MYSQL_HOST=db
- NEXTCLOUD_TRUSTED_DOMAINS=${VIRTUAL_HOST}
- NEXTCLOUD_TRUSTED_DOMAINS=proxy
env_file:
- pi.env
depends_on:
- db
networks:
- proxy-tier
- default
pi.env:
MYSQL_PASSWORD=secure-password
MYSQL_ROOT_PASSWORD=even-more-secure.password
MYSQL_DATABASE=nextcloud
MYSQL_USER=nextcloud
But thank you non the less #Zanndorin!

Answer 2

I know this is a super late answer but I just stumbled upon this while Googling something completely unrelated.
If I recall correctly you have to tell docker-compose to actually send the ENV variables to the docker by just declaring them in environment.
environment:
- MYSQL_HOST=db
- MYSQL_PASSWORD
- MYSQL_USER
I have never declared the .env-file in the docker-compose so maybe that already fixes that issue. I use it this way (I also have a .env file which I then sometimes override some values from).
Example from my developer MariaDB container:
environment:
- MYSQL_DATABASE=mydb
- MYSQL_USER=${DB_USER}
- MYSQL_PASSWORD=${DB_PASSWORD}
- MYSQL_ROOT_PASSWORD