An example on how to avoid volume permissions problems with docker (compose) with a user without root privileges
This example solves this problem with a custom entrypoint, that reads env variables to change the UID and GID of the current user of the docker container to match the desired ones (usually the current user of the host).
Take into consideration that with this solution, the container initially starts as root, but the entrypoint then switches to another user to run your command.
It is possible to use another method using the setuid bit of the script, but it has some caveats (eg. impossible to restart a container because the setuid can only be used once - so only useful for ephemeral containers).
Please note that the $UID and $GID are shell variables, not environment variables. It is not possible to use them directly in the docker compose file. So if you want to dynamically get the $UID and $GID of the current user, a script (or a makefile) can be used to set those env variables dynamically.
For example : PUID=$(id -u) PGID=$(id -g) docker compose up -d.
docker compose build --no-cache
PUID=$(id -u) PGID=$(id -g) docker compose up
# or
make run
# notice that a `ok.txt` file has been created with the correct permissions in the `data` folder
docker compose down
docker image rm vol:test- use named volumes, not bind-hosted
- use a S3 storage (eg. minio)
- use s6-overlay with
s6-setuidgid
- https://mydeveloperplanet.com/2022/10/19/docker-files-and-volumes-permission-denied/
- https://pratikpc.medium.com/use-docker-compose-named-volumes-as-non-root-within-your-containers-1911eb30f731
- https://github.com/linuxserver/docker-plex/blob/7e8f9d66876fe8e2f98ed69f20f79dc143a3c4f8/README.md?plain=1#L206-L223'
- https://github.com/linuxserver/docker-plex/blob/7e8f9d66876fe8e2f98ed69f20f79dc143a3c4f8/root/etc/s6-overlay/s6-rc.d/init-plex-chown/run#L11-L17
- https://github.com/linuxserver/docker-baseimage-ubuntu/blob/fe39690d802969da2a5ca11a04f8dd3088238fb0/root/etc/s6-overlay/s6-rc.d/init-adduser/run#L4-L8
- https://github.com/FooBarWidget/matchhostfsowner